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Heart rate monitor for scientific study

Heart rate monitor for scientific study


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I want to measure heart rate as part of a controlled experiment I am setting up. I've been trying to find information on which heart rate monitor to buy, but it's unclear to me which heart rate monitors allow exporting data to PC, and how open the data is. Can I only analyse the data through the software provided by the vendor, or is it common practice to be able to export it as e.g. CSV?

  • Are there any 'common' heartrate sensors used in the community?
  • Should I look for monitors which support a certain protocol/format?
  • Are there any vendors which I should avoid, e.g. when they have closed file formats?

I recently completed a study involving physical ergonomics of rifles. We monitored heart rate and respiration using the Zephyr BioHarness. It seemed to work pretty well.

It also monitors movement of the user, if that is of interest to you.

To get data out, it is possible to compile a report and export it to CSV, which works well if you need to do analysis on the data using other programs.


A few years ago we had very good luck using OEM pulse oximetry equipment from Nonin. Their OEM products are typically intended for other manufacturers to use in their own products. The downside is that it might take a little bit of work to configure the device at first, but the upside is that the products are eminently hackable and provide lots of information. We had a Python script that would read the heart rate data from an Xpod alongside a set of external triggers from our stimulus presentation software and then save it as a CSV file at the end of each run. Very slick!

Nonin Xpod Page: http://www.nonin.com/OEMSolutions/Xpod


Results

Spontaneous blink rates

Figure 1 shows the mean SBR (± SEM) over time with the stressor presented at the 10 min point and maintained thereafter for the duration of the experiment.

SBR over time for reactive and non-reactive horses. Mean SBR (SEM) (blinks min −1 ) for reactive and non-reactive horses (n = 33) during baseline (B) (minutes 1–10), initial treatment (IT) (minute 10, 1 min post-stressor presentation) and continued treatment (CT) (minutes 11–20 post-stressor presentation). P < 0.05 (*), P < 0.01 (**), P < 0.001 (***).

When partitioned into low (n = 16) and high (n = 17) reactive groups, the high reactive group showed a highly significant decrease in SBR during the IT period compared to baseline (11.1 ± 1.09 blinks per min to 6.2 ± 0.95 blinks per min, t1,30 = − 2.9, p = 0.008) and a significant increase in SBR from baseline during the CT period (11.1 ± 1.09 blinks per min to 15.6 ± 1.71 blinks per min, t1,30 = 2.7, p = 0.012). For the low reactive group, there was also a highly significant decrease in SBR during the IT compared to baseline, (11.4 ± 0.33 blinks per min to 5.8 ± 0.46 blinks per min, t1,32 = − 7.9, p < 0.001), but no significant difference in SBR during CT compared to baseline B (11.4 ± 0.33 blinks per min to 10.0 ± 0.67 blinks per min, t1,32 = − 1.9, p = 0.068).

Correlation of SBR with standard measures of stress

For all animals (low reactive and high reactive) combined, there was a highly significant moderate positive correlation between the change in SBR between baseline (B) and the continued treatment (CT) (ΔSBR) and change in cortisol (ΔCortisol) (r = 0.56, p < 0.001) (Fig. 2) and a highly significant strong negative correlation between ΔSBR and ΔRMSSD (r = − 0.63, p < 0.001) (Fig. 3).

Correlation of SBR with Cortisol. Correlation of change in SBR (B verses CT) against change in Cortisol (B verses CT) for all horses (low and high reactive n = 33) (r = 0.56, p < 0.001).

Correlation of SBR with RMSSD. Correlation of change in SBR (B verses CT) against change in RMSSD (B verses CT) for all horses (low and high reactive n = 33) (r = − 0.63, p < 0.001).

The HRV and cortisol results for each horse at each time-point can be found in Supplementary Table S1 online.


Are HRV devices any use?

Interpretations of the data used for HRV readings vary between practitioners and apps. HRV data is complex, which, coupled with a fair amount of debate over best practice and the efficacy of unregulated consumer products, is presumably why HRV has remained out of the public consciousness up to now.

Dr Stephen Porges, director of the Trauma Research Center in the Kinsey Institute at Indiana University, has been working with HRV and emotional resilience since the 1960s.

He was initially against consumer products being offered for HRV tracking at home, but he now concedes that, while the data from consumer devices are far from a clinical standard, such products “are helpful to people because they get them aware of their own body”. When we’re dealing with trauma and behavioural disorders, “people tend to be numb to their own bodies, and this gets them back into their body. So however they’re doing it, it’s helpful, and it’s doing no harm,” he says.

Read more about loneliness:

When I speak with Dr Marek Malik, emeritus professor of cardiac electrophysiology at Imperial College London, who was on the committee that published the first international standards for measuring HRV in 1996, he is furious.

“Some of these gadgets are inappropriate and useless,” he says. “You need to have a controlled electrocardiogram. And even gadgets that would be appropriate technically, simply are unsuitable if they are used in the wrong environment and in the wrong conditions.” He points out that HRV is affected by so many things that it’s only relevant if taken in expertly controlled conditions.

Dr Paul Lehrer, on the other hand, who recently retired from Rutgers University in New Jersey, has spent most of his career studying the use of breathing to increase HRV to treat everything from anxiety to chronic pain. He says that most devices are adequate for this work, apart from finger pulse detectors on smartphones.

So it seems that if you want to track your HRV you must be mindful that it isn’t gospel – in the same way that 10,000 steps doesn’t necessarily equate to a healthy lifestyle.


Heart Rate Monitoring on the Cheap November 12, 2013 1:53 PM Subscribe

Has she begun to seek IRB approval first? "Cheap" is rarely the first concern when dealing with physiological data. Her IRB will require her data collection and management and subject recruitment practices to fully anonymize, beyond recovery, the identity of each subject in relation to her data set, for example. Recruitment protocols are very likely to be limited to the standard method in her field.

However the standard method is usually "offer students 10 bucks." It is very difficult to recruit random strangers for free, and recruiting friends may be inappropriate for various reasons.

The other way this gets done is using someone else's existing dataset. But presumably the point is to correlate the heart rate data to some other input or condition. What is that? It matters a lot of it is, say, viewing pictures of attractive people or experiencing some form of induced stress.

This is, by the way, one reason doctoral dissertation advisers exist. Why is she asking strangers on a website (through you) and not her adviser about how to do this?
posted by spitbull at 2:06 PM on November 12, 2013 [2 favorites]

Oh, I didn't realize you meant "technically measure heart rates." The standard technique involves taking a pulse with a watch, which is free but requires training.

She could have subjects self report using the same iphone app. A lot depends on how standardized and accurate her actual research question requires the data to be. Again, adviser and IRB need to be consulted first. Make no assumptions. Pulse rate is personal medical information, governed by HIPPA regulations in some cases. Be careful.
posted by spitbull at 2:14 PM on November 12, 2013

How many people? Simultaneously or can a device be passed around? Monitoring for how long? Need long-term monitoring or short-term but high resolution data (HR over days or rapid changes over the course of tens of seconds)? 'accurately' means what here? In the lab, underwater or doing exercises?

ps: there are android and windows phone apps for this too (along with the ios one). $40 BP cuffs from your corner drug-store will also display HR. Amazon has over 1000 products from $24 upwards.
posted by Xhris at 2:17 PM on November 12, 2013 [1 favorite]

Response by poster: Thanks for your input so far everyone!

She is in the planning stage of her dissertation and will certainly get IRB approval before anything moves forward. However, she does not want to submit several different IRB applications, and in preparing a final IRB she needs to propose a specific apparatus.

Here's that additional info:

- Only one person at one time needs to be recorded. The device will need to be able to capture data for at least 100 persons, but only one device is needed.

- The task is a stress test and the individual will not be anticipating experiencing a challenging situation. Therefore, the participant should (ideally) not be able to see their heart rate at any time. However, their data should be able to be easily recorded and transmitted to use in subsequent analyses.

- The participant's heart rate needs to be recorded for at least 40 minutes, and she needs continuous data throughout the task. Specifically peak reaction (or lack thereof) to challenge and time it takes to return to baseline heart rate are the two variables of interest.

- The research questions involve physiological reactivity and self-regulation in response to an unanticipated challenge (similar to the Trier Social Stress test).

She has looked into heart rate watches and bands, but is unsure if these would be most appropriate outside of an exercise paradigm. Might they not be sensitive enough?

And of course she needs to ideally use something that isn't too new technology (to scare the IRB away) but is still pretty cheap.

Thanks everyone!
posted by zscore at 2:43 PM on November 12, 2013

Response by poster: Thanks for the input all.

It seems like she's done her homework and unfortunately, it seems like almost all the research in this area in psychology (which is relatively new to psychology) is done with pretty expensive equipment setups (Mindware Technologies/BioLab). My friend is familiar with this equipment, knows how to use it, but does not have access to it.

The closest anyone has come seems to be Actiwave Cardio from Camntech http://camntech.com/products/actiwave-cardio/actiwave-cardio-overview
but it costs $3,000 per pack.

She wants to bring some novel ideas perhaps from other disciplines to her advisor/program and think creatively about how to get her dissertation work done on a budget (

if anyone out there knows of any specific studies/justification/feasibility for monitoring heart rate using consumer-level heart rate watches or other inexpensive technology that would be most useful.
posted by zscore at 3:13 PM on November 12, 2013

Perhaps Polar makes one that will provide your friend with this data? http://www.polar.com/us-en/products Surely one of the heart rate monitors out there meant for athletes would have a feature that would cover a 40 minute stretch and download to a computer.

I have a $40 Polar heart rate monitor for running and it works great for me. I think mine just tells me the current heart rate, though, and does not store anything. An more expensive heart rate monitor might do more (but not be too expensive for the intended purpose).
posted by AllieTessKipp at 3:37 PM on November 12, 2013

Will the test subjects have their hands free? If so, you could use this hand held monitor. The school could already have the appropriate data logging software ("LoggerPro")- I've used it in chemistry and geology classes, so far (for temperature probes, pH probes, etc.)

As a result of a grant or Vernier promotion or something, there's a full set of sensors in one of my geology labs, including some of the more medical probes. If this probe sounds like it would work, she should start asking around some of the science departments and see if there's one stashed someplace random.
posted by Secretariat at 5:45 PM on November 12, 2013

Best answer: I have two options to suggest:

1- Get a sport watch that pairs with an around-the-chest heart rate monitor. For example, the Garmin Forerunner series can record HR for several hours with no problem. You complete each “workout” between participants then when the session is complete, upload to Garmin Connect website. From there, you will be able to export the HR results as a CSV file and import in Excel.

One possible advantage is that you only need to have the watch within a range of 6-8 feet during the experiment, or have them wear it with the watch face taped over. The participants can then get up and move around, not only stay seated and pluged into a computer.

2- If you want to skip the sports watch and record to the computer directly, you would need software such as SportTracks with the Live Recording and HRV plugin (Shareware/Paid plugin). I have not used it before but looks like it would do the job. You would need a Garmin USB ANT+ Stick (

50$) for the computer to receive the data and an Ant+ Heart Rate Monitor (

Best option would be to buy the Garmin FR70 for 130$. It comes with the watch, the HR monitor strap and the USB receiver. That way you have all the equipment needed to try out both solutions for not a lot of money. I use Garmin as an example here because it is what I use and know but Polar and other brands can probably do the same.

In all cases, if she uses a heart rate monitor that contacts the skin directly, investing in a tube of electrode gel (5$) will ensure consistent results with no drop outs. It is what doctors use during actual medial test to ensure proper contact.
posted by TinTitan at 8:43 AM on November 13, 2013

Best answer: From a perspective of an athlete who has used heart rate measurement, there are several different things meant by "heart rate". Most of the time it just means beats per minute. This is the easiest thing to catalog and there are affordable tools for doing this.

The more complicated side of the house is analyzing the stroke itself. For this you find EKG and heart rate variability tools. These are used to measure stress levels. Athletes use HRV in particular to identify patterns that indicate over training. There are some new tools that are much more affordable in this area now.

If she needs the medical grade devices I wonder if it might be possible to contact the manufacturers and make a strong case for buying one at a discount. They might have a refurb model or they may just feel generous.
posted by dgran at 11:46 AM on November 13, 2013

Best answer: This device should be up to the job and it is very inexpensive: Bitalino

Might require some programming!
posted by benign at 6:18 PM on November 13, 2013


Raising individual and global consciousness can help us improve personal and collective health, well-being and harmony. We suggest that this begins with people taking greater responsibility for their day-to-day decisions, actions and behaviors, which can result in establishing a new and healthier physiological and psychological internal baseline reference. Establishing a baseline requires having effective and practical strategies available for handling daily situations, making good decisions and taking meaningful and appropriate action.

Much attention has been given to identifying the many factors that go into making good decisions. Among these are awareness of self and others, cognitive flexibility and self-regulation of emotions. All of these are important for bringing more consciousness into our daily situations and the decisions we make. Something else that should be considered in good decision-making &ndash and we&rsquove all experienced it, perhaps without being fully aware of it &ndash is intuition. There is fascinating research that is beginning to uncover the nature and function of intuition, or what researchers refer to as intuitive intelligence. In a literature review of intuition, Gerard Hodgkinson of Leeds University in England notes that despite the many conceptualizations of intuition, there is a growing body of research suggesting there are underlying nonconscious aspects of intuition. Among the nonconscious aspects of intuition which are involved in intuitive perception are implicit learning, or implicit knowledge. [224] It is commonly acknowledged that intuitive perception plays an important role in business decisions and entrepreneurship, learning, medical diagnosis, healing, spiritual growth and overall well-being. [225, 226]

Research also suggests intuition may play an important role in social cognition, decision-making and creativity. When addressing life situations, people often default to familiar patterns of thoughts, feelings and actions in both the decision-making process and how they see others.

Rather than responding to situations from habitual patterns that are not necessarily healthy or constructive, those situations could be more effectively addressed with new and creative solutions. These solutions can take into consideration the available inner resources that are congruent with one&rsquos deeper intuition and core values. In other words, we can learn to intentionally align with and access our intuitive intelligence, which can provide moment-to-moment guidance and empower what HeartMath calls heartbased living, reliance in all things on the wisdom, intelligence and qualities of the heart.

The origin of the word "intuition" is the Latin verb intueri, which is usually translated as to look inside or to contemplate. Hodgkinson concludes that "intuiting" is a complex set of interrelated cognitive, affective and somatic processes in which there is no apparent intrusion of deliberate, rational thought. He also concludes that the considerable body of theory and research that has emerged in recent years demonstrates that the concept of intuition has emerged as a legitimate subject of scientific inquiry that has important ramifications for educational, personal, medical and organizational decision-making, personnel selection and assessment, team dynamics, training and organizational development. [224] Another comprehensive review of intuition literature yielded this definition of intuition: "Affectively charged judgments that arise through rapid, nonconscious and holistic associations." [227]

Several researchers have contended that intuition is an innate ability that all humans possess in one form or another and is arguably the most universal natural ability we possess. They also say the ability to intuit could be regarded as an inherited unlearned gift. [228, 229] A common element also found in most discussions and definitions of intuition is that of affect or emotions. Although intuitions are felt, they can be accompanied by cognitive content and perception of information. Our research and experience suggests that emotions are the primary language of intuition and that intuition offers a largely untapped resource to manage and uplift our emotions, daily experience and consciousness.

Types of Intuition

Our research at the HeartMath Institute suggests there are three categories or types of processes the word intuition describes. The first type of intuition, often called implicit knowledge or implicit learning, essentially refers to knowledge we&rsquove acquired in the past and either forgot or did not realize we had learned. Drawing on the neuroscience conception of the human brain as a highly efficient and effective patternmatching device, [176] a number of pattern-recognition models have been developed to show how this fast type of intuitive decision-making and action can be understood purely in terms of neural processes. In this regard, the brain matches the patterns of new problems or challenges with implicit memories based on prior experience. [224, 230, 231]

The second type of intuition is what we call energetic sensitivity, which refers to the ability of the nervous system to detect and respond to environmental signals such as electromagnetic fields (also see Energetic Communication section). It is well established that in both humans and animals, nervous-system activity is affected by geomagnetic activity. [232] Some people, for example, appear to have the capacity to feel or sense that an earthquake is about to occur before it happens. It has recently been shown that changes in the earth&rsquos magnetic field can be detected about an hour or even longer before a large earthquake occurs. [231] Another example of energetic sensitivity is the sense of being stared at. Several scientific studies have verified this type of sensitivity. [234]

The third type of intuition is nonlocal intuition, which refers to the knowledge or sense of something that cannot be explained by past or forgotten knowledge or by sensing environmental signals. It has been suggested that the capacity to receive and process information about nonlocal events appears to be a property of all physical and biological organization and this likely is because of an inherent interconnectedness of everything in the universe. [235-237] Examples of nonlocal intuition include when a parent senses something is happening to his or her child who is many miles away, or the repeated, successful sensing experienced by entrepreneurs about factors related to making effective business decisions.

Figure 7.1 The three types of intuition.

Implicit Learning

The question of how intuition interacts with deliberate, conscious thought processes, has long been the subject of debate. Research in the fields of cognitive and social psychology has produced the commonly accepted dual-process theory, which suggests there are two separate processing systems. The first system is unconscious, automatic and intuitive. It processes information very rapidly and associates current inputs to the brain with past experiences. Therefore, it is relatively undemanding in its use of cognitive resources. For example, when individuals have gained experience in a particular field, implicit intuitions are derived from their capacity to recognize important environmental cues and rapidly and unconsciously match those cues to existing familiar patterns. This results in rapid and effective diagnosis or problem-solving. In contrast, the second processing system is conscious in nature, relatively slow, rule-based and analytic. It places greater demands on cognitive resources than the first system. [224]

Insight

The term intuition also is used commonly to describe experiences scientific literature refers to as insight. When we have a problem we cannot immediately solve, the brain can be working on it subconsciously. It is common when we are in the shower, driving or doing something else and not thinking about the problem that a solution pops into the conscious mind, a process we experience as an intuitive insight. This type of implicit process involves a longer gestation period following an impasse in problem-solving before a sudden insightful perception or strategy that leads to a solution. [238] In contrast, intuition in the dual-processing models of implicit intuition described above occurs almost instantaneously and is emotionally charged. [239]

Nonlocal Intuition

The study of nonlocal intuition, which at times has been thought of as being in the same category as telepathy, clairvoyance and precognition, has been fraught with debate in the scientific community. [240] While there are various theories that attempt to explain how the process of intuition functions, these theories have yet to be confirmed, so an integrated theory remains to be formulated. Nevertheless, there is now a large body of documented rigorous scientific research on nonlocal intuitive perception that dates back more than seven decades. A variety of experiments show it cannot be explained by flaws in experimental design or research methods, statistical techniques, chance or selective reporting of results. [239]

A meta-analysis of nine experiments that measured physiological responses occurring before a future event (pre-stimulus responses) that could not otherwise be anticipated through any known inferential process, revealed statistically significant results in eight of the nine studies in over 1,000 subjects. [240] Subsequent to this, a researcher, by examining 26 studies, also concluded that a clear pre-stimulus response in physiological activity occurred before unpredictable stimuli, despite the fact there is not yet any known explanation of the mechanisms for this finding. [242]

There is compelling evidence to suggest the physical heart is coupled to a field of information not bound by the classical limits of time and space. [243, 244] This evidence comes from a rigorous experimental study that demonstrated the heart receives and processes information about a future event before the event actually happens. [243, 244]

Figure 7.2 The heart&rsquos pre-stimulus response. The graph shows group averages of the heart rate variability (blue and red lines) and skin conductance level (pink and green lines) responses. The "0" time point denotes when the photos were first shown, when participants saw either an emotionally arousing or calm picture. Pre-stimulus responses which indicate nonlocal intuition are in the period between -6 and 0 seconds. The red line is the HRV trace when the future photo was an emotional one, and the blue line shows the HRV for calming future photos. The highly significant difference between the HRV responses in the pre-stimulus period before the future calm or emotional photos can clearly be seen starting to diverge approximately 4.8 seconds prior to the participants actually seeing the photos.

Extending and building on Radin&rsquos protocol designed to evoke an emotional response using randomly selected, emotionally arousing or calming photographs, we added measures of brain response (EEG) and heart-rhythm activity (ECG) and found that not only did both the brain and heart receive the pre-stimulus information some 4 to 5 seconds before a future emotional picture was randomly selected by the computer, the heart actually received this information about 1.5 seconds before the brain received it (Figure 7.3). [244]

Figure 7.3 Example of temporal dynamics of heart and brain pre-stimulus responses. This overlay plot shows the mean event-related potential (ERP) at EEG site FP2 and heart-rate deceleration curves during the pre-stimulus period. (The "0" time point denotes stimulus onset.) The heart-rate deceleration curve for the trials, in which a negative emotionally arousing photo would be seen in the future, diverged from that of trials containing a calming future picture (sharp downward shift) about 4.8 seconds before the stimulus (arrow 1). The emotional trials ERP showed a sharp positive shift about 3.5 seconds before the stimulus (arrow 2). This positive shift in the ERP indicates when the brain "knew" the nature of the future stimulus. The time difference between these two events suggests that the heart received the intuitive information about 1.3 seconds before the brain. Heartbeat-evoked potential analysis confirmed that a different afferent signal was sent by the heart to the brain during this period. [244]

A number of studies have since found evidence of the heart&rsquos role in reflecting future or distant events. [245-251] Using a combination of cortical-evoked potentials and heartbeat-evoked potentials, these studies also found that when the participants were in the physiological coherence mode before the trials, the afferent input from the heart and cardiovascular system modulated changes in the brain&rsquos electrical activity, especially at the frontal areas of the brain. In other words, participants were more attuned to information from the heart while in a coherent state before participating in the experimental protocol. Therefore, being in a state of psychophysiological coherence is expected to enhance intuitive ability. [244]

This suggests the heart is directly coupled to a source of information that interacts with the multiplicity of energetic fields in which the body is embedded. We also found further evidence that the magnitude of prestimulus response to a future event is related to the degree of emotionality associated with that event. [243]

Nonlocal Intuition in Repeat Entrepreneurs

A study conducted in Iran with a group of 30 repeat entrepreneurs in the science and technology parks of the city of Tehran duplicated and extended our first study of intuition. [251] Repeat entrepreneurs were chosen for this study because they are most likely to have demonstrated that their success is not the result of luck alone and they have beaten the odds against success. Also, studies have shown that they have a strong tendency to rely on their intuitions when making important business decisions. The study was modeled after our study, described above, whose stimulus was a computer-administered random sequence of calm and emotional pictures. However, this study added a new element: Researchers conducted two separate experiments.

The first, with a group of single participants (N = 15), and the second, with a group of co-participant pairs (N = 30), investigated the "amplification" of intuition effects by social connection. In the experiment for single participants, the participant watched the pictures on a monitor alone, while in the experiment for co-participant pairs, each pair watched the same pictures simultaneously on two monitors while sitting facing each other, as illustrated in Figure 7.4.

Figure 7.4 Setup for Single Participant Experiment and Co-participant Pair Experiment.

Each experiment was conducted over 45 trials while heart-rate rhythm activity was recorded continuously. In both experiments, the results showed significant pre-stimulus results, meaning for the period before the computer had randomly selected the picture stimulus. Moreover, while significant separation between the emotional and calm HRV curves was observed in the single-participant experiment, an even larger separation was apparent for the experiment with co-participant pairs, and the difference between the two groups also was significant. Overall, the results of the single-participant experiment confirm our and others&rsquo previous finding that electrophysiological measures, especially changes in heart rhythm, can demonstrate intuitive foreknowledge. This result is notable because, having come from experiments in Iran, it constituted cross-cultural corroboration in a non-Western context. In addition, the results for coparticipant pairs offer new evidence on the amplification of the nonlocal intuition signal.

Full-Moon Effect on Amplifying Intuition

We also evaluated an updated version of a roulette protocol we developed that includes two pre-stimulus segments. This study included an analysis of individual data analysis and group-level data analysis for 13 participants over eight separate trials. [252] We also assessed the potential effects of the moon phase on the pre-stimulus response outcomes and participant winning and amount-won ratios. Half of the experimental sessions were conducted during the full-moon phase and half during the new-moon phase. Within each trial, a total of three segments of physiological data were assessed. There were two separate prestimulus periods, a pre-bet (4-seconds) and post-bet (12-seconds), and a post-result period (6-seconds). Participants were told they were participating in a gambling experiment, given an initial starting kitty and informed that they could keep any winnings over the course of 26 trials for each of the eight sessions. The physiological measures included the ECG, from which cardiac interbeat intervals (HRV) were derived and skin conductance.

Overall, the results indicate the protocol provides an effective objective method for measuring and detecting a pre-stimulus response, which demonstrates a type of nonlocal intuition. We found significant differences between the win and loss responses in the aggregated physiological waveform data during both pre-stimulus segments (Figure 7.5).

On average, we detected a significant pre-stimulus response starting around 18 seconds before participants knew the future outcome. Interestingly, there was not a strong overall relationship between the pre-stimulus responses and the amount of money the participants won or lost. We also found a significant difference in both pre-stimulus periods during the fullmoon phase, when they also won more money, but not in the new-moon phase (Figure 7.6). Overall, the findings also suggest that if participants had been able to become more attuned to their internal cardiac related pre-stimulus responses, they would have performed much better on the betting choices they made.

Figure 7.5 Multisession roulette paradigm study. Grand averages are shown for the skin conductance levels and HRV win/loss waveform differences in response to winning or losing for all 13 participants across all eight trials for the three segments of the experiment: pre-bet, post-bet and post-result periods. * = (p < 0.05), ** = (p < 0.01), *** = (p < 0.001).

Figure 7.6 Multisession roulette paradigm study. Shown are grand averages by moon phase for the skin conductance levels and HRV win/loss waveforms results. There was a significant difference in the HRV win/loss waveforms in both the pre-bet (p < 0.01) and post-bet (p < 0.05) periods during the full-moon phase and no significant difference during the new-moon phase. * = (p < 0.05), ** = (p < 0.01), *** = (p < 0.001).

Heart Intelligence

Because the heart plays a central role in creating physiological coherence and is associated with heartfelt positive emotions and intuition, it is not surprising that one of the strongest threads uniting the views of diverse cultures and religious and spiritual traditions throughout history has been a universal regard that it is the source of love, wisdom, intuition, courage, etc. Everyone is familiar with such expressions as "put your heart into it," "learn it by heart" and "speak from your heart." All of these suggest an implicit knowledge that the heart is more than a physical pump that sustains life. Such expressions reflect what often is called the intuitive, or spiritual heart. Throughout history, people have turned to the intuitive heart &ndash also referred to as their inner voice, soul or higher power &ndash as a source of wisdom and guidance.

We suggest that the terms intuitive heart and spiritual heart refer to our energetic heart, which we believe is coupled with a deeper part of ourselves. Many refer to this as their higher self or higher capacities, or what physicist David Bohm described as "our implicate order and undivided wholeness." [235] We use the term energetic systems in this context to refer to the functions we cannot directly measure, touch or see, such as our emotions, thoughts and intuitions. Although these functions have loose correlations with biological activity patterns, they nevertheless remain covert and hidden from direct observation. Several notable scientists have proposed that such functions operate primarily in the frequency domain outside of time and space and they have suggested some of the possible mechanisms that govern how they are able to interact with biological processes. [206, 253-259]

As discussed in the Heart-Brain Communication chapter of this work, the physical heart has extensive afferent connections to the brain and can modulate perception and emotional experience. [5] Our experience suggests that the physical heart also has communication channels connecting it with the energetic heart. [244] Nonlocal intuition, therefore, is transformational, and from our perspective, it contains the wisdom that streams from the soul&rsquos higher information field down into the psychophysiological system via the energetic heart and can inform our moment-tomoment experiences and interactions. At HeartMath Institute, this is what we call heart intelligence.

Heart intelligence is the flow of higher awareness and the intuition we experience when the mind and emotions are brought into synchronistic alignment with the energetic heart. When we are heart-centered and coherent, we have a tighter coupling and closer alignment with our deeper source of intuitive intelligence. We are able to more intelligently self-regulate our thoughts and emotions and over time this lifts consciousness and establishes a new internal physiological and psychological baseline. [244] In other words, there is an increased flow of intuitive information that is communicated via the emotional energetic system to the mind and brain systems, resulting in a stronger connection with our deeper inner voice.

Accessing Intuition

Although people&rsquos degree of access to the heart&rsquos intuition varies, we all have access to the three types of intuition. As we learn to slow down our minds and attune to our deeper heart feelings, a natural intuitive connection can occur. Intuition often is thought of in the context of inventing a new lightbulb or winning in Las Vegas, but what most people discover is that intuition is a very practical asset that can help guide their moment-to-moment choices and decisions in daily life. Our intuitive insights often unfold more understanding of ourselves, others, issues and life than years of accumulated knowledge. It is especially helpful for eliminating unnecessary energy expenditures, which deplete our internal reserves, making it more difficult to self-regulate and be in charge of our attitudes, emotions and behaviors in ordinary day-to-day life situations. Intuition allows us to increase our ability to move beyond automatic reactions and perceptions. It helps us make more intelligent decisions from a deeper source of wisdom, intelligence and balanced discernment, in essence increasing our consciousness, happiness and the quality of our life experience. This increases synchronicities and enhances our creativity and ability to flow through life. It also increases our ability to handle awkward situations such as dealing with difficult people with more ease and it promotes harmonious interaction and connectivity with others.

It is important to understand that conscious awareness of anything, including our emotions and intuitive promptings, is not possible until something has captured our attention. [260] Sensory neurons in our eyes, ears, nose and body are continuously active day and night, whether we are awake or asleep. The brain receives a steady stream of information about all the events the sensory systems are detecting. It would be bewildering if we were continuously aware of all the incoming information from both our external and internal environments. In fact, we completely ignore most of the information arriving to the brain &ndash most of the time. It is when inputs are large, sudden or novel or lead to an emotional reaction that they capture and focus our attention and that we become aware of them. [206]

Voluntary attention, on the other hand, describes the process in which we can consciously self-regulate and determine the contents of our own awareness as well as the duration of our focus. Current evidence suggests that this self-regulatory capacity relies on an inner resource akin to energy, which is used to interrupt the stream of consciousness and behavior and alter it. When this limited energy has been depleted, further efforts at self-regulation are less successful than usual. [261] With practice, however, the capacity to self-regulate can be increased and give us more energy resources to sustain self-directed control. Importantly, these practices also are keys to establishing a new baseline and once a new baseline is established, the new patterns of self-regulation become automatic and therefore do not require the same energy expenditure.

One of the most important keys to accessing more of our intuitive intelligence and inner sense of knowing is developing deeper levels of self-awareness of our more subtle feelings and perceptions, which otherwise never rise to conscious awareness. In other words, we have to pay attention to the intuitive signals that often are under the radar of conscious perception or are drowned out by ongoing mental chatter and emotional unrest. A common report from people who practice being more self-aware of their inner signals is that the heart communicates a steady stream of intuitive information to the mind and brain. In many cases, we only perceive a small percentage of intuitive information or choose to override the signals because they do not match our more egocentric desires.

Given that there is a relationship between increased heart coherence and access to intuitive signals, [244] the capacity to shift into a coherent state is an important factor in the three types of intuition: implicit knowledge/learning, energetic sensitivity and nonlocal intuition. The research discussed above suggests it&rsquos possible to access intuitive intelligence more effectively by first getting into a coherent state, quieting mental chatter and emotional unrest and paying attention to shifts in our feelings, a process that brings intuitive signals to conscious awareness. [262] We have found that increased heart-rhythm coherence correlates with significant improvements in performance on tasks requiring attentional focus and subtle discrimination. [5] We&rsquove also found that heart-rhythm coherence correlates with pre-stimulus-related afferent (ascending) signals from the heart to the brain. [244]

It is likely that these signals are important elements of intuition that are particularly salient in pattern recognition and that they are involved in all types of intuitive processes.

The Freeze Frame Technique, [179, 182] is a five-step process that was designed for improving intuitive capacities, stopping energy drains, shifting perspective, obtaining greater clarity and finding innovative solutions to problems or issues.


Your Fitness Tracker Isn’t the Best Way to Measure Heart Rate

Does that fitness tracker or smart watch on your wrist measure you heart rate? Many do, in the name of helping you stay healthy.

Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy

While some wrist-worn monitors are more accurate than others, studies show they generally aren’t as accurate as chest-worn heart monitors, says Chairman of the Department of Thoracic and Cardiovascular Surgery Marc Gillinov, MD, who has studied the accuracy of these devices.

How these devices work

Chest-worn heart rate monitors are used by serious runners, distance cyclists and other elite athletes. They work in a similar way to an electrocardiogram (EKG), which your physician uses for diagnostic purposes. Both devices detect and measure the electrical signal that the heart transmits when it beats.

When you get an EKG, electrodes are attached to your skin and the EKG device, which records your heart’s electrical activity. A computer draws a picture on graph paper from information supplied by the electrodes.

Similarly, a chest-worn heart monitor consists of two parts ⁠— a transmitter attached to a belt worn around the chest, and a receiver worn on the wrist like a watch. The transmitter picks up the electric signal and then sends an electromagnetic signal containing heart rate data to the wrist receiver, which displays the heart rate.

The fitness tracker heart rate monitors, on the other hand, use optical sensors to detect the blood coursing through your veins. They have some recognized drawbacks.

For example, because they’re on your wrist, optical heart rate sensors read your blood flow when it’s farther from your heart. Their accuracy also can be reduced by light hitting the sensor as you move your arm or flex your wrist.

Comparing the monitors

In one 2017 study, Dr. Gillinov and his fellow researchers recruited 50 healthy adults and randomly assigned each of them to wear two of four wrist-worn fitness devices with heart rate monitors (one on each wrist) while walking or running on a treadmill. All the participants also wore standard EKG electrodes and a chest-worn monitor.

Heart rate was measured with participants resting and walking or running on the treadmill at various speeds. The participants exercised for three minutes at each setting, with heart rate recorded at the three-minute point. Recovery heart rate was also measured at 30, 60 and 90 seconds at the end of the three minutes.

The researchers found that the most accurate readings ⁠— as measured against the EKG ⁠— were from the chest-worn monitor, Dr. Gillinov says. Other studies have also found that fitness devices slightly underestimate heart rate, and that their accuracy diminishes during exercise.

The value of fitness trackers

Wrist-worn monitors are fine for recreational use, Dr. Gillinov says. But they probably won’t be replacing EKGs in the medical setting any time soon.

Heart patients who want to make sure they’re staying within safe, physician-recommended heart rate thresholds during rehabilitation and exercise would be better off using a chest-worn monitor for the most precise information, Dr. Gillinov says.

“The wrist-worn fitness devices that include heart rate monitors are incredibly popular, but if you really want to know your heart rate, wear the chest strap heart monitor because that senses electricity,” he says.

If you do still want to use a fitness tracker, Dr. Gillinov advises taking several measurements to get the most accurate reading.

“Don’t make too much of a single reading, or even two readings,” he says. “Do several readings because you can’t count on these devices to be accurate every time.”

Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy


From feelings to physiology

Even after taking into account both partners’ daytime heart rate, stress levels, drug or alcohol use and physical activity, we found that men’s overnight heart rate changed depending on how women felt toward their partner throughout the day.

When women felt closer and more connected to their partners during the day, men had lower overnight heart rates. When women felt more annoyed and irritated with their partners during the day, men had higher overnight heart rates. On average, men’s overnight heart rates were about 2 to 4 beats per minute slower in couples where women expressed more closeness. On the other hand, men’s heart rates were about 1.5 to 3 beats per minute faster if women expressed greater annoyance.

Interestingly, we found that women’s annoyance did not predict increases in men’s heart rate, if women also felt close to their partners throughout the day. In other words, the negative effects of annoyance got diluted if some closeness was also in the mix.

There were actually no effects of men’s annoyance or closeness on women’s overnight heart rates – men’s cardiovascular responses appeared to be uniquely sensitive to women’s daytime relationship feelings. Other research has found similar gender differences. One possibility is that women are more likely to express their feelings of closeness or annoyance, whereas men may feel less comfortable engaging in such communication.

Of course, every relationship has its natural ups and downs, and our study only captures a snapshot of young dating couples’ lives together. However, the findings suggest the way romantic partners feel about one another, even within a single day, can have acute effects on their biological functioning during sleep.

These seemingly trivial, everyday experiences could build up over time and help explain why relationships wind up affecting people’s health – for better or for worse.

[You need to understand the coronavirus pandemic, and we can help. Read The Conversation’s newsletter.]

This article is republished from The Conversation under a Creative Commons license. Read the original article.


WELLBEING AND HEALTH

For Wellbeing and Health

Heart rate variability (HRV) is a measure of cardiac autonomic nervous system function and has been associated with multiple cardiovascular diseases and risk factors. In addition, HRV is a commonly used tool in assessing stress and recovery. Kubios HRV software products provide easy-to-use measurement applications and detailed HRV analysis tools for health and wellbeing professionals who want to use HRV assessment as part of their services.


Frontiers in Psychology

The editor and reviewers' affiliations are the latest provided on their Loop research profiles and may not reflect their situation at the time of review.



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Scientific Comparison of Different Online Heart Rate Monitoring Systems

Recent technical development focused on real-time heart rate monitoring instead of postexercise evaluation of recorded data. There are several systems on the market that allow direct and real-time monitoring of several individuals at the same time. The present study compared the systems of Polar, Acentas, Activio, and Suunto in a field test with twelve subjects regarding failure quota, operating distance, and ECG validity. Moreover, the installation and use of software and hardware were evaluated with a quality rating system. Chest belts were evaluated with a questionnaire, too. Overall the system of Acentas reached the best mark of all systems, but detailed results showed that every system has its advantages and disadvantages depending on using purpose, location, and weather. So this evaluation cannot recommend a single system but rather shows strength and weakness of all systems and additionally can be used for further system improvements.

1. Introduction

Over the last 25 years, heart rate monitors have been widely used in sports and sports science. Since the development of handy heart rate monitors (HRMs) with the size of a watch and appropriate flexible chest belts with electrodes to transmit signals wirelessly to the watch, measurement of heart rate (HR) has become an easily accessible and valuable tool for training and coaching purposes and conducting laboratory or field studies [1]. Validity and reliability have been shown to be high for these tools compared to ECG measurements for both HR and heart rate variability (HRV) [1–6]. Owed to its widespread use in physical activity not only for individuals but also for team sports, recent technical development focused on real-time monitoring instead of post-exercise evaluation of recorded data. This led to both software and hardware development of wireless online HR monitoring systems. Currently, several different systems are available on the market, of which four were tested in the present study: POLAR Team 2 Pro, Acentas team monitoring system, Suunto Pro Team Pack and Activio Sport System. All systems allow direct and real-time monitoring of several individuals at the same time. Data are transmitted wirelessly to a receiver which is connected with a standard laptop with relevant software. However, a direct comparison of these systems and validity of recorded data are missing in literature. Therefore the main purpose of this study was to compare all systems in a field test against each other. Operating distance and validity against a commercially available ECG were evaluated as well as the installation and use of software and hardware of the above-mentioned systems.

2. Methods

2.1. Subjects

A total of 12 active people (11 men and 1 woman age:

cm mass: kg) participated in the study. Ten men of an amateur soccer team conducted an online field test during a real football match. One male subject participated for validity of HR monitoring systems against ECG whereas the female subject was only involved in operating distance measurement. Because of the low case number of the last two tests, data can only be considered as a pilot study for ECG validation and distance measurement.

2.2. Heart Rate Monitoring Systems

The following four commercially available systems were used for all tests: POLAR Team 2 Pro (Polar Electro Oy, Kempele, Finland), Acentas team monitoring system (Acentas GmbH, Hörgertshausen, Germany), Suunto Pro Team Pack (Suunto Oy, Vantaa, Finland), and Activio Sport System (Activio AB, Stockholm, Sweden).

2.3. Quality Rating System

A quality rating system similar to rating systems used in trade journals was used to test electronic equipment and software. A valuable design was found in the journal “Connect” (http://www.connect.de/) which is specialised on the testing of mobile and electronic communication tools. For this purpose, the authors decide to subdivide the rating system into three main categories: measurement, software, and hardware. At this, the core area of the study focused on the adequate online measurement of the heart rate. Therefore, the rating system was set in favour of the measurement which was represented by 200 scores of maximal 500. The latter 300 were equally divided on quality of the hardware and the usability of the software. Detailed distribution into the several subcategories is depicted in Table 1. Subcategories were weighted subjectively by the authors in consideration of heart rate monitoring of team sports including the monitoring of 10 or more subjects in parallel. In addition, the following subcategories were rated once by an independent observer who was not familiar with any of the monitor systems to get a first impression: instruction manual, packing, chest belts (quality), and initial software handling. The remaining categories were judged once by an experienced person. With exception of wearing comfort and failing quota in field, all subcategories were judged and quantified by using a ten-stepped visual analogue scale which is known for pain assessment [7]. Visual analogue scaling was weighted by multiplying itself with factor

: ( = maximal score of subcategory/10). Parameters leading the judgement of the subcategories are described in Tables 2 and 4.

SystemAcentasActivioPolarSuunto
Instruction manual
(language, comprehensibility, volume, usefulness)
(i) Short and compact but sufficient (+)(i) Very detailed IM in English (+)
(ii) Easily comprehensible (+)
(i) Short instruction in six languages (+)
(ii) Laminated (+)
(iii) Personal instruction by member of staff (+)
(iv) Useful (+)
(v) Only short hardware & installation instruction (−)
(i) No instruction manual (−)
Packing
(quality, handling)
(i) Compact backpack (<1 kg) (+)
(ii) Good accessibility & separation of hardware (+)
(iii) Poor quality of packing system (−)
(i) Good arrangement of hardware (+)
(ii) Heavy (+2 kg) (−)
(iii) Hardware & software not fixed in packing (−)
(iv) Poor quality of packing system (−)
(i) Carrying case (+)
(ii) Good quality of packing system (+)
(iii) Good arrangement of single system parts (+)
(iv) Heavy (

Wearing comfort of the chest belts was evaluated via a short anonymous questionnaire which all 12 participants (see Section 2.1) had to complete directly after wearing. The questionnaire contained five questions about the handling and individual fitting of the chest belts. The questions one and two are positively formulated whereas questions three to five are negative (see Table 3). All questions had to be answered by an even scaled rating system including six categories. The six different categories range from “totally agree” = 5 points to “absolutely disagree” = 0 points. To compare positively and negatively formulated questions, the negative one was transformed before mean value was calculated. Maximum score for the whole questionnaire was 25 hence, each question was scored with maximal 5 points.

2.4. Measurements

The main field test was measurement of failure ratio during the half time of a real soccer match. All players apart from goal keeper were equipped with chest belts of the relevant system and measured during first half (= 45 min) of a league soccer game during four home matches in summer 2009. Temperature range was within 9°C, and weather conditions were similar (no precipitation) for all measurements. The receiver of the relevant system was always positioned three meters in projection of midline of the soccer ground. In order to improve transmission distance, receiver was positioned one meter above ground level. As data loss due to injury could not be excluded a priori, a mean failure ratio was determined only with transmitters sending valid data. Each deviation/loss of one percent of whole duration measurement of 45 min (= 2700 s) was subtracted with 10 scores, and a maximal score of 100 could be obtained. If, for example, a total loss time of all ten transmitters of a system was 270 s, a total score of 90 would be credited to this system. A failure ratio of 10 percent of whole duration measurement would be credited with a zero score.

Distance measurement was conducted on a uphill street with a constant slope and in far distance to high-voltage line or radio tower to reduce possible interference. Receiver antenna was placed on highest elevation of the hill one meter above ground, and unit was connected to a laptop (Toshiba Satellite Series Toshiba Inc, NY, USA). The participants wearing the chest belts were equipped with a GPS device (Nokia N79, Nokia Group, Espoo, Finland) to measure distance. By moving backwards it was guaranteed that the chest belt transmitters were permanently faced to the receiver. Measurements were terminated when transmission signal was lost. Additionally, the participants were instructed to move arms to keep HR variable with time. Attempts were only started when both valid signals of GPS and HR were available and stopped when HR signal was lost. Tests were conducted twice, and mean value of both attempts was calculated and taken as maximal range. Maximal range distance was credited with 70 scores whereas the system with the absolute maximal covered range was taken as reference system and credited maximum score. Percentage deviation of distance of other systems was analogously deducted as percentage of scores. If, for example, reference system had 100 m range, it was credited 70 scores. If a second system had only 50 m range, it would be credited 50% of maximum score, hence 35.

Comparison against ECG was conducted in a laboratory by using ECG tool Vicardio ECP-6 standard (Energy-Lab Technologies, Hamburg, Germany). Measurement was conducted two minutes at rest with single-polar extremity drains. Mean HRs of both ECG and relevant system were compared. A maximum score of 30 could be obtained at this test. A deviation of 1 beat per minute (bpm) was deducted with two scores. Only complete accordance of both values was credited with maximum score.

3. Results

3.1. Comparison of Hardware

Results for hardware are summarized in Table 2. A plus (+) is a positive feature a minus (−) is a negative one. If all systems were similar or identical, there is no separate classification. A plus/minus (±) indicates aspects which are both positive and negative. In context of the supplied hardware Acentas and Polar lead the field of monitor systems, both reaching 100 and 106 scores in sum for the hardware. The leading position of Polar depends on the storage capacity of the chest belt increasing data safety but also decreasing wearing performance which is indicated by the chest-belt questionnaire presented in Table 3. In case of wearing comfort, it has to be noted that both chest belts of Activio and Acentas were supplied by the identical manufacture. Both Polar and Acentas delivered high-quality receivers.

3.2. Comparison of Software

Results of software evaluation are summarized in Table 4. Again, similar to hardware evaluation, a plus (+) is a positive feature, and a minus (−) is a negative one. If all systems were similar or identical, there is no separate classification. A plus/minus (±) indicates aspects which are both positive and negative. Here, Activio offered the harmonious concept which led to the highest ranking. The installation procedure was easiest with the Acentas software, but Acentas did not focus on extensive statistical analysis. In this case, Polar as well as Activia provide a more developed software tool.

3.3. Measurement Results

As data of ECG comparison were only obtained with a single subject, they have to be regarded with caution. Further evaluation would be necessary to confirm or reject results. Data are represented against reference system. Acentas had 86 bpm average HR versus 88 of reference system. Suunto’s deviation was 80 to 85 bpm, Activio’s deviation was 81 to 85 bpm, and Polar’s deviation was 82 to 85 bpm, respectively. Score distribution is depicted in Table 5. Concerning distance measurement, same caution has to be taken as only one subject’s data were included in analysis. Nevertheless, Acentas gave reference with 349 m, followed by Activio with 141 m and Suunto with 107.5 m. It has to be noted that Activio’s system was supposed to reach 300 m. Last but not least, Polar reached 102 m which corresponded to the manufacturer information for this system. Nevertheless, all other systems had a wider range of data acquisition, and hence score distribution was credited as follows: Acentas 70, Activio 28, Suunto 21, and Polar 20.

Regarding failure quota, average downtime was 148 s (0,6%) for Acentas, 286 s (1,0%) for Polar, and 552 s (2,0%) for Activio. The Suunto system stood out negatively, as a complete data loss was seen. Single belts were recognised from time to time, but no consistent data acquisition could be accomplished. A receiver problem might have caused this failure. Therefore, Suunto was not scored at all in this test. Similarly, five out of ten Polar chest belts had signal loss and could not be reactivated whereas Activio managed 10 out of 10 signals, and for the Acentas system 9 out of 10 were used for data evaluation as one person was injured during match play. The summarized scores and overall results are represented in Table 5.

4. Discussion

The purpose of the present study was to compare four commercially available online heart rate monitoring systems and especially their use in everyday situation in team sports. The system of Polar could score especially with a clear design, useable features of the software, and a convincing product quality. Only Polar uses WLAN for data transmission and also adds a mobile terminal in pocket format which can easily be used outdoor and with bad weather conditions. But the high energy consumption of WLAN transmission would terminate the battery capacities and additionally the duration of measurement. The system of Activio has a functional and useful software and the instruction manual was very detailed and easily comprehensible. The price, however, was very high compared with the other systems. Acentas could score with a huge operating distance, a valid heart rate signal compared with ECG, a low failure quota, and an easy handling. In contrast, the system of Suunto had a total breakdown during competition measurements and could not be reactivated. So this system was evaluated as the worst. The evaluation of the several chest belts revealed no important advantage of one manufacturer. Only the chest belt of Polar showed weaknesses regarding wearing comfort. Altogether, all systems cannot be used for online heart rate monitoring. Prospectively, it would be a great challenge to realise online monitoring for swimmers, possibly leading to new opportunities for the training regime. In this context the system of Polar and Suunto had the advantage that data are also recorded on the chest belt memory during water immersion and could be evaluated after exercise.

Meanwhile, some of the tested heart rate monitoring systems are updated and upgraded with new functions, respectively. For example, Acentas included an offline memory in the chest belts and added a wrist monitor for direct heart rate analysis from up to twenty athletes by the coach.

In summary, Acentas system reached the best mark of all systems, but every system has its advantages and disadvantages depending on the using purpose, location, and weather. So this present comparative study cannot recommend a single system but rather shows strength and weakness of all systems and additionally can be used for further system improvements.

Disclosures

The investigators were responsible for the study design, data collection, data analysis, data interpretation, and submission of the paper for publication, independently of all funding sources. The authors declare that they have no financial conflict of interests to disclose with any of the companies named in this paper. There is no preferential order of companies in the paper.

Acknowledgment

The authors thank all manufactures for the delivery of evaluation systems with no charge.

References

  1. J. Achten and A. E. Jeukendrup, “Heart rate monitoring: applications and limitations,” Sports Medicine, vol. 33, no. 7, pp. 517–538, 2003. View at: Publisher Site | Google Scholar
  2. F. X. Gamelin, S. Berthoin, and L. Bosquet, “Validity of the polar S810 Heart rate monitor to measure R-R intervals at rest,” Medicine and Science in Sports and Exercise, vol. 38, no. 5, pp. 887–893, 2006. View at: Publisher Site | Google Scholar
  3. M. Kingsley, M. J. Lewis, and R. E. Marson, “Comparison of Polar 810s and an ambulatory ECG system for RR interval measurement during progressive exercise,” International Journal of Sports Medicine, vol. 26, no. 1, pp. 39–44, 2005. View at: Publisher Site | Google Scholar
  4. H. Kinnunen and I. Heikkila, “The timing accuracy of the Polar Vantage NV heart rate monitor,” Journal of sports sciences, vol. 16, p. 107, 1998. View at: Google Scholar
  5. L. Leger and M. Thivierge, “Heart rate monitors: validity, stability, and functionality,” Physician and Sportsmedicine, vol. 16, no. 5, pp. 143–148, 1988. View at: Google Scholar
  6. M. Thivierge and L. Leger, “The reliability of heart rate monitors,” Science and Sports, vol. 3, no. 3, pp. 211–221, 1988. View at: Google Scholar
  7. B. A. Lord and B. Parsell, “Measurement of pain in the prehospital setting using a visual analogue scale,” Prehospital and Disaster Medicine, vol. 18, no. 4, pp. 353–358, 2003. View at: Google Scholar

Copyright

Copyright © 2011 Martin Schönfelder et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Your Fitness Tracker Isn’t the Best Way to Measure Heart Rate

Does that fitness tracker or smart watch on your wrist measure you heart rate? Many do, in the name of helping you stay healthy.

Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy

While some wrist-worn monitors are more accurate than others, studies show they generally aren’t as accurate as chest-worn heart monitors, says Chairman of the Department of Thoracic and Cardiovascular Surgery Marc Gillinov, MD, who has studied the accuracy of these devices.

How these devices work

Chest-worn heart rate monitors are used by serious runners, distance cyclists and other elite athletes. They work in a similar way to an electrocardiogram (EKG), which your physician uses for diagnostic purposes. Both devices detect and measure the electrical signal that the heart transmits when it beats.

When you get an EKG, electrodes are attached to your skin and the EKG device, which records your heart’s electrical activity. A computer draws a picture on graph paper from information supplied by the electrodes.

Similarly, a chest-worn heart monitor consists of two parts ⁠— a transmitter attached to a belt worn around the chest, and a receiver worn on the wrist like a watch. The transmitter picks up the electric signal and then sends an electromagnetic signal containing heart rate data to the wrist receiver, which displays the heart rate.

The fitness tracker heart rate monitors, on the other hand, use optical sensors to detect the blood coursing through your veins. They have some recognized drawbacks.

For example, because they’re on your wrist, optical heart rate sensors read your blood flow when it’s farther from your heart. Their accuracy also can be reduced by light hitting the sensor as you move your arm or flex your wrist.

Comparing the monitors

In one 2017 study, Dr. Gillinov and his fellow researchers recruited 50 healthy adults and randomly assigned each of them to wear two of four wrist-worn fitness devices with heart rate monitors (one on each wrist) while walking or running on a treadmill. All the participants also wore standard EKG electrodes and a chest-worn monitor.

Heart rate was measured with participants resting and walking or running on the treadmill at various speeds. The participants exercised for three minutes at each setting, with heart rate recorded at the three-minute point. Recovery heart rate was also measured at 30, 60 and 90 seconds at the end of the three minutes.

The researchers found that the most accurate readings ⁠— as measured against the EKG ⁠— were from the chest-worn monitor, Dr. Gillinov says. Other studies have also found that fitness devices slightly underestimate heart rate, and that their accuracy diminishes during exercise.

The value of fitness trackers

Wrist-worn monitors are fine for recreational use, Dr. Gillinov says. But they probably won’t be replacing EKGs in the medical setting any time soon.

Heart patients who want to make sure they’re staying within safe, physician-recommended heart rate thresholds during rehabilitation and exercise would be better off using a chest-worn monitor for the most precise information, Dr. Gillinov says.

“The wrist-worn fitness devices that include heart rate monitors are incredibly popular, but if you really want to know your heart rate, wear the chest strap heart monitor because that senses electricity,” he says.

If you do still want to use a fitness tracker, Dr. Gillinov advises taking several measurements to get the most accurate reading.

“Don’t make too much of a single reading, or even two readings,” he says. “Do several readings because you can’t count on these devices to be accurate every time.”

Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy


From feelings to physiology

Even after taking into account both partners’ daytime heart rate, stress levels, drug or alcohol use and physical activity, we found that men’s overnight heart rate changed depending on how women felt toward their partner throughout the day.

When women felt closer and more connected to their partners during the day, men had lower overnight heart rates. When women felt more annoyed and irritated with their partners during the day, men had higher overnight heart rates. On average, men’s overnight heart rates were about 2 to 4 beats per minute slower in couples where women expressed more closeness. On the other hand, men’s heart rates were about 1.5 to 3 beats per minute faster if women expressed greater annoyance.

Interestingly, we found that women’s annoyance did not predict increases in men’s heart rate, if women also felt close to their partners throughout the day. In other words, the negative effects of annoyance got diluted if some closeness was also in the mix.

There were actually no effects of men’s annoyance or closeness on women’s overnight heart rates – men’s cardiovascular responses appeared to be uniquely sensitive to women’s daytime relationship feelings. Other research has found similar gender differences. One possibility is that women are more likely to express their feelings of closeness or annoyance, whereas men may feel less comfortable engaging in such communication.

Of course, every relationship has its natural ups and downs, and our study only captures a snapshot of young dating couples’ lives together. However, the findings suggest the way romantic partners feel about one another, even within a single day, can have acute effects on their biological functioning during sleep.

These seemingly trivial, everyday experiences could build up over time and help explain why relationships wind up affecting people’s health – for better or for worse.

[You need to understand the coronavirus pandemic, and we can help. Read The Conversation’s newsletter.]

This article is republished from The Conversation under a Creative Commons license. Read the original article.


Frontiers in Psychology

The editor and reviewers' affiliations are the latest provided on their Loop research profiles and may not reflect their situation at the time of review.



SHARE ON

WELLBEING AND HEALTH

For Wellbeing and Health

Heart rate variability (HRV) is a measure of cardiac autonomic nervous system function and has been associated with multiple cardiovascular diseases and risk factors. In addition, HRV is a commonly used tool in assessing stress and recovery. Kubios HRV software products provide easy-to-use measurement applications and detailed HRV analysis tools for health and wellbeing professionals who want to use HRV assessment as part of their services.


Are HRV devices any use?

Interpretations of the data used for HRV readings vary between practitioners and apps. HRV data is complex, which, coupled with a fair amount of debate over best practice and the efficacy of unregulated consumer products, is presumably why HRV has remained out of the public consciousness up to now.

Dr Stephen Porges, director of the Trauma Research Center in the Kinsey Institute at Indiana University, has been working with HRV and emotional resilience since the 1960s.

He was initially against consumer products being offered for HRV tracking at home, but he now concedes that, while the data from consumer devices are far from a clinical standard, such products “are helpful to people because they get them aware of their own body”. When we’re dealing with trauma and behavioural disorders, “people tend to be numb to their own bodies, and this gets them back into their body. So however they’re doing it, it’s helpful, and it’s doing no harm,” he says.

Read more about loneliness:

When I speak with Dr Marek Malik, emeritus professor of cardiac electrophysiology at Imperial College London, who was on the committee that published the first international standards for measuring HRV in 1996, he is furious.

“Some of these gadgets are inappropriate and useless,” he says. “You need to have a controlled electrocardiogram. And even gadgets that would be appropriate technically, simply are unsuitable if they are used in the wrong environment and in the wrong conditions.” He points out that HRV is affected by so many things that it’s only relevant if taken in expertly controlled conditions.

Dr Paul Lehrer, on the other hand, who recently retired from Rutgers University in New Jersey, has spent most of his career studying the use of breathing to increase HRV to treat everything from anxiety to chronic pain. He says that most devices are adequate for this work, apart from finger pulse detectors on smartphones.

So it seems that if you want to track your HRV you must be mindful that it isn’t gospel – in the same way that 10,000 steps doesn’t necessarily equate to a healthy lifestyle.


Raising individual and global consciousness can help us improve personal and collective health, well-being and harmony. We suggest that this begins with people taking greater responsibility for their day-to-day decisions, actions and behaviors, which can result in establishing a new and healthier physiological and psychological internal baseline reference. Establishing a baseline requires having effective and practical strategies available for handling daily situations, making good decisions and taking meaningful and appropriate action.

Much attention has been given to identifying the many factors that go into making good decisions. Among these are awareness of self and others, cognitive flexibility and self-regulation of emotions. All of these are important for bringing more consciousness into our daily situations and the decisions we make. Something else that should be considered in good decision-making &ndash and we&rsquove all experienced it, perhaps without being fully aware of it &ndash is intuition. There is fascinating research that is beginning to uncover the nature and function of intuition, or what researchers refer to as intuitive intelligence. In a literature review of intuition, Gerard Hodgkinson of Leeds University in England notes that despite the many conceptualizations of intuition, there is a growing body of research suggesting there are underlying nonconscious aspects of intuition. Among the nonconscious aspects of intuition which are involved in intuitive perception are implicit learning, or implicit knowledge. [224] It is commonly acknowledged that intuitive perception plays an important role in business decisions and entrepreneurship, learning, medical diagnosis, healing, spiritual growth and overall well-being. [225, 226]

Research also suggests intuition may play an important role in social cognition, decision-making and creativity. When addressing life situations, people often default to familiar patterns of thoughts, feelings and actions in both the decision-making process and how they see others.

Rather than responding to situations from habitual patterns that are not necessarily healthy or constructive, those situations could be more effectively addressed with new and creative solutions. These solutions can take into consideration the available inner resources that are congruent with one&rsquos deeper intuition and core values. In other words, we can learn to intentionally align with and access our intuitive intelligence, which can provide moment-to-moment guidance and empower what HeartMath calls heartbased living, reliance in all things on the wisdom, intelligence and qualities of the heart.

The origin of the word "intuition" is the Latin verb intueri, which is usually translated as to look inside or to contemplate. Hodgkinson concludes that "intuiting" is a complex set of interrelated cognitive, affective and somatic processes in which there is no apparent intrusion of deliberate, rational thought. He also concludes that the considerable body of theory and research that has emerged in recent years demonstrates that the concept of intuition has emerged as a legitimate subject of scientific inquiry that has important ramifications for educational, personal, medical and organizational decision-making, personnel selection and assessment, team dynamics, training and organizational development. [224] Another comprehensive review of intuition literature yielded this definition of intuition: "Affectively charged judgments that arise through rapid, nonconscious and holistic associations." [227]

Several researchers have contended that intuition is an innate ability that all humans possess in one form or another and is arguably the most universal natural ability we possess. They also say the ability to intuit could be regarded as an inherited unlearned gift. [228, 229] A common element also found in most discussions and definitions of intuition is that of affect or emotions. Although intuitions are felt, they can be accompanied by cognitive content and perception of information. Our research and experience suggests that emotions are the primary language of intuition and that intuition offers a largely untapped resource to manage and uplift our emotions, daily experience and consciousness.

Types of Intuition

Our research at the HeartMath Institute suggests there are three categories or types of processes the word intuition describes. The first type of intuition, often called implicit knowledge or implicit learning, essentially refers to knowledge we&rsquove acquired in the past and either forgot or did not realize we had learned. Drawing on the neuroscience conception of the human brain as a highly efficient and effective patternmatching device, [176] a number of pattern-recognition models have been developed to show how this fast type of intuitive decision-making and action can be understood purely in terms of neural processes. In this regard, the brain matches the patterns of new problems or challenges with implicit memories based on prior experience. [224, 230, 231]

The second type of intuition is what we call energetic sensitivity, which refers to the ability of the nervous system to detect and respond to environmental signals such as electromagnetic fields (also see Energetic Communication section). It is well established that in both humans and animals, nervous-system activity is affected by geomagnetic activity. [232] Some people, for example, appear to have the capacity to feel or sense that an earthquake is about to occur before it happens. It has recently been shown that changes in the earth&rsquos magnetic field can be detected about an hour or even longer before a large earthquake occurs. [231] Another example of energetic sensitivity is the sense of being stared at. Several scientific studies have verified this type of sensitivity. [234]

The third type of intuition is nonlocal intuition, which refers to the knowledge or sense of something that cannot be explained by past or forgotten knowledge or by sensing environmental signals. It has been suggested that the capacity to receive and process information about nonlocal events appears to be a property of all physical and biological organization and this likely is because of an inherent interconnectedness of everything in the universe. [235-237] Examples of nonlocal intuition include when a parent senses something is happening to his or her child who is many miles away, or the repeated, successful sensing experienced by entrepreneurs about factors related to making effective business decisions.

Figure 7.1 The three types of intuition.

Implicit Learning

The question of how intuition interacts with deliberate, conscious thought processes, has long been the subject of debate. Research in the fields of cognitive and social psychology has produced the commonly accepted dual-process theory, which suggests there are two separate processing systems. The first system is unconscious, automatic and intuitive. It processes information very rapidly and associates current inputs to the brain with past experiences. Therefore, it is relatively undemanding in its use of cognitive resources. For example, when individuals have gained experience in a particular field, implicit intuitions are derived from their capacity to recognize important environmental cues and rapidly and unconsciously match those cues to existing familiar patterns. This results in rapid and effective diagnosis or problem-solving. In contrast, the second processing system is conscious in nature, relatively slow, rule-based and analytic. It places greater demands on cognitive resources than the first system. [224]

Insight

The term intuition also is used commonly to describe experiences scientific literature refers to as insight. When we have a problem we cannot immediately solve, the brain can be working on it subconsciously. It is common when we are in the shower, driving or doing something else and not thinking about the problem that a solution pops into the conscious mind, a process we experience as an intuitive insight. This type of implicit process involves a longer gestation period following an impasse in problem-solving before a sudden insightful perception or strategy that leads to a solution. [238] In contrast, intuition in the dual-processing models of implicit intuition described above occurs almost instantaneously and is emotionally charged. [239]

Nonlocal Intuition

The study of nonlocal intuition, which at times has been thought of as being in the same category as telepathy, clairvoyance and precognition, has been fraught with debate in the scientific community. [240] While there are various theories that attempt to explain how the process of intuition functions, these theories have yet to be confirmed, so an integrated theory remains to be formulated. Nevertheless, there is now a large body of documented rigorous scientific research on nonlocal intuitive perception that dates back more than seven decades. A variety of experiments show it cannot be explained by flaws in experimental design or research methods, statistical techniques, chance or selective reporting of results. [239]

A meta-analysis of nine experiments that measured physiological responses occurring before a future event (pre-stimulus responses) that could not otherwise be anticipated through any known inferential process, revealed statistically significant results in eight of the nine studies in over 1,000 subjects. [240] Subsequent to this, a researcher, by examining 26 studies, also concluded that a clear pre-stimulus response in physiological activity occurred before unpredictable stimuli, despite the fact there is not yet any known explanation of the mechanisms for this finding. [242]

There is compelling evidence to suggest the physical heart is coupled to a field of information not bound by the classical limits of time and space. [243, 244] This evidence comes from a rigorous experimental study that demonstrated the heart receives and processes information about a future event before the event actually happens. [243, 244]

Figure 7.2 The heart&rsquos pre-stimulus response. The graph shows group averages of the heart rate variability (blue and red lines) and skin conductance level (pink and green lines) responses. The "0" time point denotes when the photos were first shown, when participants saw either an emotionally arousing or calm picture. Pre-stimulus responses which indicate nonlocal intuition are in the period between -6 and 0 seconds. The red line is the HRV trace when the future photo was an emotional one, and the blue line shows the HRV for calming future photos. The highly significant difference between the HRV responses in the pre-stimulus period before the future calm or emotional photos can clearly be seen starting to diverge approximately 4.8 seconds prior to the participants actually seeing the photos.

Extending and building on Radin&rsquos protocol designed to evoke an emotional response using randomly selected, emotionally arousing or calming photographs, we added measures of brain response (EEG) and heart-rhythm activity (ECG) and found that not only did both the brain and heart receive the pre-stimulus information some 4 to 5 seconds before a future emotional picture was randomly selected by the computer, the heart actually received this information about 1.5 seconds before the brain received it (Figure 7.3). [244]

Figure 7.3 Example of temporal dynamics of heart and brain pre-stimulus responses. This overlay plot shows the mean event-related potential (ERP) at EEG site FP2 and heart-rate deceleration curves during the pre-stimulus period. (The "0" time point denotes stimulus onset.) The heart-rate deceleration curve for the trials, in which a negative emotionally arousing photo would be seen in the future, diverged from that of trials containing a calming future picture (sharp downward shift) about 4.8 seconds before the stimulus (arrow 1). The emotional trials ERP showed a sharp positive shift about 3.5 seconds before the stimulus (arrow 2). This positive shift in the ERP indicates when the brain "knew" the nature of the future stimulus. The time difference between these two events suggests that the heart received the intuitive information about 1.3 seconds before the brain. Heartbeat-evoked potential analysis confirmed that a different afferent signal was sent by the heart to the brain during this period. [244]

A number of studies have since found evidence of the heart&rsquos role in reflecting future or distant events. [245-251] Using a combination of cortical-evoked potentials and heartbeat-evoked potentials, these studies also found that when the participants were in the physiological coherence mode before the trials, the afferent input from the heart and cardiovascular system modulated changes in the brain&rsquos electrical activity, especially at the frontal areas of the brain. In other words, participants were more attuned to information from the heart while in a coherent state before participating in the experimental protocol. Therefore, being in a state of psychophysiological coherence is expected to enhance intuitive ability. [244]

This suggests the heart is directly coupled to a source of information that interacts with the multiplicity of energetic fields in which the body is embedded. We also found further evidence that the magnitude of prestimulus response to a future event is related to the degree of emotionality associated with that event. [243]

Nonlocal Intuition in Repeat Entrepreneurs

A study conducted in Iran with a group of 30 repeat entrepreneurs in the science and technology parks of the city of Tehran duplicated and extended our first study of intuition. [251] Repeat entrepreneurs were chosen for this study because they are most likely to have demonstrated that their success is not the result of luck alone and they have beaten the odds against success. Also, studies have shown that they have a strong tendency to rely on their intuitions when making important business decisions. The study was modeled after our study, described above, whose stimulus was a computer-administered random sequence of calm and emotional pictures. However, this study added a new element: Researchers conducted two separate experiments.

The first, with a group of single participants (N = 15), and the second, with a group of co-participant pairs (N = 30), investigated the "amplification" of intuition effects by social connection. In the experiment for single participants, the participant watched the pictures on a monitor alone, while in the experiment for co-participant pairs, each pair watched the same pictures simultaneously on two monitors while sitting facing each other, as illustrated in Figure 7.4.

Figure 7.4 Setup for Single Participant Experiment and Co-participant Pair Experiment.

Each experiment was conducted over 45 trials while heart-rate rhythm activity was recorded continuously. In both experiments, the results showed significant pre-stimulus results, meaning for the period before the computer had randomly selected the picture stimulus. Moreover, while significant separation between the emotional and calm HRV curves was observed in the single-participant experiment, an even larger separation was apparent for the experiment with co-participant pairs, and the difference between the two groups also was significant. Overall, the results of the single-participant experiment confirm our and others&rsquo previous finding that electrophysiological measures, especially changes in heart rhythm, can demonstrate intuitive foreknowledge. This result is notable because, having come from experiments in Iran, it constituted cross-cultural corroboration in a non-Western context. In addition, the results for coparticipant pairs offer new evidence on the amplification of the nonlocal intuition signal.

Full-Moon Effect on Amplifying Intuition

We also evaluated an updated version of a roulette protocol we developed that includes two pre-stimulus segments. This study included an analysis of individual data analysis and group-level data analysis for 13 participants over eight separate trials. [252] We also assessed the potential effects of the moon phase on the pre-stimulus response outcomes and participant winning and amount-won ratios. Half of the experimental sessions were conducted during the full-moon phase and half during the new-moon phase. Within each trial, a total of three segments of physiological data were assessed. There were two separate prestimulus periods, a pre-bet (4-seconds) and post-bet (12-seconds), and a post-result period (6-seconds). Participants were told they were participating in a gambling experiment, given an initial starting kitty and informed that they could keep any winnings over the course of 26 trials for each of the eight sessions. The physiological measures included the ECG, from which cardiac interbeat intervals (HRV) were derived and skin conductance.

Overall, the results indicate the protocol provides an effective objective method for measuring and detecting a pre-stimulus response, which demonstrates a type of nonlocal intuition. We found significant differences between the win and loss responses in the aggregated physiological waveform data during both pre-stimulus segments (Figure 7.5).

On average, we detected a significant pre-stimulus response starting around 18 seconds before participants knew the future outcome. Interestingly, there was not a strong overall relationship between the pre-stimulus responses and the amount of money the participants won or lost. We also found a significant difference in both pre-stimulus periods during the fullmoon phase, when they also won more money, but not in the new-moon phase (Figure 7.6). Overall, the findings also suggest that if participants had been able to become more attuned to their internal cardiac related pre-stimulus responses, they would have performed much better on the betting choices they made.

Figure 7.5 Multisession roulette paradigm study. Grand averages are shown for the skin conductance levels and HRV win/loss waveform differences in response to winning or losing for all 13 participants across all eight trials for the three segments of the experiment: pre-bet, post-bet and post-result periods. * = (p < 0.05), ** = (p < 0.01), *** = (p < 0.001).

Figure 7.6 Multisession roulette paradigm study. Shown are grand averages by moon phase for the skin conductance levels and HRV win/loss waveforms results. There was a significant difference in the HRV win/loss waveforms in both the pre-bet (p < 0.01) and post-bet (p < 0.05) periods during the full-moon phase and no significant difference during the new-moon phase. * = (p < 0.05), ** = (p < 0.01), *** = (p < 0.001).

Heart Intelligence

Because the heart plays a central role in creating physiological coherence and is associated with heartfelt positive emotions and intuition, it is not surprising that one of the strongest threads uniting the views of diverse cultures and religious and spiritual traditions throughout history has been a universal regard that it is the source of love, wisdom, intuition, courage, etc. Everyone is familiar with such expressions as "put your heart into it," "learn it by heart" and "speak from your heart." All of these suggest an implicit knowledge that the heart is more than a physical pump that sustains life. Such expressions reflect what often is called the intuitive, or spiritual heart. Throughout history, people have turned to the intuitive heart &ndash also referred to as their inner voice, soul or higher power &ndash as a source of wisdom and guidance.

We suggest that the terms intuitive heart and spiritual heart refer to our energetic heart, which we believe is coupled with a deeper part of ourselves. Many refer to this as their higher self or higher capacities, or what physicist David Bohm described as "our implicate order and undivided wholeness." [235] We use the term energetic systems in this context to refer to the functions we cannot directly measure, touch or see, such as our emotions, thoughts and intuitions. Although these functions have loose correlations with biological activity patterns, they nevertheless remain covert and hidden from direct observation. Several notable scientists have proposed that such functions operate primarily in the frequency domain outside of time and space and they have suggested some of the possible mechanisms that govern how they are able to interact with biological processes. [206, 253-259]

As discussed in the Heart-Brain Communication chapter of this work, the physical heart has extensive afferent connections to the brain and can modulate perception and emotional experience. [5] Our experience suggests that the physical heart also has communication channels connecting it with the energetic heart. [244] Nonlocal intuition, therefore, is transformational, and from our perspective, it contains the wisdom that streams from the soul&rsquos higher information field down into the psychophysiological system via the energetic heart and can inform our moment-tomoment experiences and interactions. At HeartMath Institute, this is what we call heart intelligence.

Heart intelligence is the flow of higher awareness and the intuition we experience when the mind and emotions are brought into synchronistic alignment with the energetic heart. When we are heart-centered and coherent, we have a tighter coupling and closer alignment with our deeper source of intuitive intelligence. We are able to more intelligently self-regulate our thoughts and emotions and over time this lifts consciousness and establishes a new internal physiological and psychological baseline. [244] In other words, there is an increased flow of intuitive information that is communicated via the emotional energetic system to the mind and brain systems, resulting in a stronger connection with our deeper inner voice.

Accessing Intuition

Although people&rsquos degree of access to the heart&rsquos intuition varies, we all have access to the three types of intuition. As we learn to slow down our minds and attune to our deeper heart feelings, a natural intuitive connection can occur. Intuition often is thought of in the context of inventing a new lightbulb or winning in Las Vegas, but what most people discover is that intuition is a very practical asset that can help guide their moment-to-moment choices and decisions in daily life. Our intuitive insights often unfold more understanding of ourselves, others, issues and life than years of accumulated knowledge. It is especially helpful for eliminating unnecessary energy expenditures, which deplete our internal reserves, making it more difficult to self-regulate and be in charge of our attitudes, emotions and behaviors in ordinary day-to-day life situations. Intuition allows us to increase our ability to move beyond automatic reactions and perceptions. It helps us make more intelligent decisions from a deeper source of wisdom, intelligence and balanced discernment, in essence increasing our consciousness, happiness and the quality of our life experience. This increases synchronicities and enhances our creativity and ability to flow through life. It also increases our ability to handle awkward situations such as dealing with difficult people with more ease and it promotes harmonious interaction and connectivity with others.

It is important to understand that conscious awareness of anything, including our emotions and intuitive promptings, is not possible until something has captured our attention. [260] Sensory neurons in our eyes, ears, nose and body are continuously active day and night, whether we are awake or asleep. The brain receives a steady stream of information about all the events the sensory systems are detecting. It would be bewildering if we were continuously aware of all the incoming information from both our external and internal environments. In fact, we completely ignore most of the information arriving to the brain &ndash most of the time. It is when inputs are large, sudden or novel or lead to an emotional reaction that they capture and focus our attention and that we become aware of them. [206]

Voluntary attention, on the other hand, describes the process in which we can consciously self-regulate and determine the contents of our own awareness as well as the duration of our focus. Current evidence suggests that this self-regulatory capacity relies on an inner resource akin to energy, which is used to interrupt the stream of consciousness and behavior and alter it. When this limited energy has been depleted, further efforts at self-regulation are less successful than usual. [261] With practice, however, the capacity to self-regulate can be increased and give us more energy resources to sustain self-directed control. Importantly, these practices also are keys to establishing a new baseline and once a new baseline is established, the new patterns of self-regulation become automatic and therefore do not require the same energy expenditure.

One of the most important keys to accessing more of our intuitive intelligence and inner sense of knowing is developing deeper levels of self-awareness of our more subtle feelings and perceptions, which otherwise never rise to conscious awareness. In other words, we have to pay attention to the intuitive signals that often are under the radar of conscious perception or are drowned out by ongoing mental chatter and emotional unrest. A common report from people who practice being more self-aware of their inner signals is that the heart communicates a steady stream of intuitive information to the mind and brain. In many cases, we only perceive a small percentage of intuitive information or choose to override the signals because they do not match our more egocentric desires.

Given that there is a relationship between increased heart coherence and access to intuitive signals, [244] the capacity to shift into a coherent state is an important factor in the three types of intuition: implicit knowledge/learning, energetic sensitivity and nonlocal intuition. The research discussed above suggests it&rsquos possible to access intuitive intelligence more effectively by first getting into a coherent state, quieting mental chatter and emotional unrest and paying attention to shifts in our feelings, a process that brings intuitive signals to conscious awareness. [262] We have found that increased heart-rhythm coherence correlates with significant improvements in performance on tasks requiring attentional focus and subtle discrimination. [5] We&rsquove also found that heart-rhythm coherence correlates with pre-stimulus-related afferent (ascending) signals from the heart to the brain. [244]

It is likely that these signals are important elements of intuition that are particularly salient in pattern recognition and that they are involved in all types of intuitive processes.

The Freeze Frame Technique, [179, 182] is a five-step process that was designed for improving intuitive capacities, stopping energy drains, shifting perspective, obtaining greater clarity and finding innovative solutions to problems or issues.


Scientific Comparison of Different Online Heart Rate Monitoring Systems

Recent technical development focused on real-time heart rate monitoring instead of postexercise evaluation of recorded data. There are several systems on the market that allow direct and real-time monitoring of several individuals at the same time. The present study compared the systems of Polar, Acentas, Activio, and Suunto in a field test with twelve subjects regarding failure quota, operating distance, and ECG validity. Moreover, the installation and use of software and hardware were evaluated with a quality rating system. Chest belts were evaluated with a questionnaire, too. Overall the system of Acentas reached the best mark of all systems, but detailed results showed that every system has its advantages and disadvantages depending on using purpose, location, and weather. So this evaluation cannot recommend a single system but rather shows strength and weakness of all systems and additionally can be used for further system improvements.

1. Introduction

Over the last 25 years, heart rate monitors have been widely used in sports and sports science. Since the development of handy heart rate monitors (HRMs) with the size of a watch and appropriate flexible chest belts with electrodes to transmit signals wirelessly to the watch, measurement of heart rate (HR) has become an easily accessible and valuable tool for training and coaching purposes and conducting laboratory or field studies [1]. Validity and reliability have been shown to be high for these tools compared to ECG measurements for both HR and heart rate variability (HRV) [1–6]. Owed to its widespread use in physical activity not only for individuals but also for team sports, recent technical development focused on real-time monitoring instead of post-exercise evaluation of recorded data. This led to both software and hardware development of wireless online HR monitoring systems. Currently, several different systems are available on the market, of which four were tested in the present study: POLAR Team 2 Pro, Acentas team monitoring system, Suunto Pro Team Pack and Activio Sport System. All systems allow direct and real-time monitoring of several individuals at the same time. Data are transmitted wirelessly to a receiver which is connected with a standard laptop with relevant software. However, a direct comparison of these systems and validity of recorded data are missing in literature. Therefore the main purpose of this study was to compare all systems in a field test against each other. Operating distance and validity against a commercially available ECG were evaluated as well as the installation and use of software and hardware of the above-mentioned systems.

2. Methods

2.1. Subjects

A total of 12 active people (11 men and 1 woman age:

cm mass: kg) participated in the study. Ten men of an amateur soccer team conducted an online field test during a real football match. One male subject participated for validity of HR monitoring systems against ECG whereas the female subject was only involved in operating distance measurement. Because of the low case number of the last two tests, data can only be considered as a pilot study for ECG validation and distance measurement.

2.2. Heart Rate Monitoring Systems

The following four commercially available systems were used for all tests: POLAR Team 2 Pro (Polar Electro Oy, Kempele, Finland), Acentas team monitoring system (Acentas GmbH, Hörgertshausen, Germany), Suunto Pro Team Pack (Suunto Oy, Vantaa, Finland), and Activio Sport System (Activio AB, Stockholm, Sweden).

2.3. Quality Rating System

A quality rating system similar to rating systems used in trade journals was used to test electronic equipment and software. A valuable design was found in the journal “Connect” (http://www.connect.de/) which is specialised on the testing of mobile and electronic communication tools. For this purpose, the authors decide to subdivide the rating system into three main categories: measurement, software, and hardware. At this, the core area of the study focused on the adequate online measurement of the heart rate. Therefore, the rating system was set in favour of the measurement which was represented by 200 scores of maximal 500. The latter 300 were equally divided on quality of the hardware and the usability of the software. Detailed distribution into the several subcategories is depicted in Table 1. Subcategories were weighted subjectively by the authors in consideration of heart rate monitoring of team sports including the monitoring of 10 or more subjects in parallel. In addition, the following subcategories were rated once by an independent observer who was not familiar with any of the monitor systems to get a first impression: instruction manual, packing, chest belts (quality), and initial software handling. The remaining categories were judged once by an experienced person. With exception of wearing comfort and failing quota in field, all subcategories were judged and quantified by using a ten-stepped visual analogue scale which is known for pain assessment [7]. Visual analogue scaling was weighted by multiplying itself with factor

: ( = maximal score of subcategory/10). Parameters leading the judgement of the subcategories are described in Tables 2 and 4.

SystemAcentasActivioPolarSuunto
Instruction manual
(language, comprehensibility, volume, usefulness)
(i) Short and compact but sufficient (+)(i) Very detailed IM in English (+)
(ii) Easily comprehensible (+)
(i) Short instruction in six languages (+)
(ii) Laminated (+)
(iii) Personal instruction by member of staff (+)
(iv) Useful (+)
(v) Only short hardware & installation instruction (−)
(i) No instruction manual (−)
Packing
(quality, handling)
(i) Compact backpack (<1 kg) (+)
(ii) Good accessibility & separation of hardware (+)
(iii) Poor quality of packing system (−)
(i) Good arrangement of hardware (+)
(ii) Heavy (+2 kg) (−)
(iii) Hardware & software not fixed in packing (−)
(iv) Poor quality of packing system (−)
(i) Carrying case (+)
(ii) Good quality of packing system (+)
(iii) Good arrangement of single system parts (+)
(iv) Heavy (

Wearing comfort of the chest belts was evaluated via a short anonymous questionnaire which all 12 participants (see Section 2.1) had to complete directly after wearing. The questionnaire contained five questions about the handling and individual fitting of the chest belts. The questions one and two are positively formulated whereas questions three to five are negative (see Table 3). All questions had to be answered by an even scaled rating system including six categories. The six different categories range from “totally agree” = 5 points to “absolutely disagree” = 0 points. To compare positively and negatively formulated questions, the negative one was transformed before mean value was calculated. Maximum score for the whole questionnaire was 25 hence, each question was scored with maximal 5 points.

2.4. Measurements

The main field test was measurement of failure ratio during the half time of a real soccer match. All players apart from goal keeper were equipped with chest belts of the relevant system and measured during first half (= 45 min) of a league soccer game during four home matches in summer 2009. Temperature range was within 9°C, and weather conditions were similar (no precipitation) for all measurements. The receiver of the relevant system was always positioned three meters in projection of midline of the soccer ground. In order to improve transmission distance, receiver was positioned one meter above ground level. As data loss due to injury could not be excluded a priori, a mean failure ratio was determined only with transmitters sending valid data. Each deviation/loss of one percent of whole duration measurement of 45 min (= 2700 s) was subtracted with 10 scores, and a maximal score of 100 could be obtained. If, for example, a total loss time of all ten transmitters of a system was 270 s, a total score of 90 would be credited to this system. A failure ratio of 10 percent of whole duration measurement would be credited with a zero score.

Distance measurement was conducted on a uphill street with a constant slope and in far distance to high-voltage line or radio tower to reduce possible interference. Receiver antenna was placed on highest elevation of the hill one meter above ground, and unit was connected to a laptop (Toshiba Satellite Series Toshiba Inc, NY, USA). The participants wearing the chest belts were equipped with a GPS device (Nokia N79, Nokia Group, Espoo, Finland) to measure distance. By moving backwards it was guaranteed that the chest belt transmitters were permanently faced to the receiver. Measurements were terminated when transmission signal was lost. Additionally, the participants were instructed to move arms to keep HR variable with time. Attempts were only started when both valid signals of GPS and HR were available and stopped when HR signal was lost. Tests were conducted twice, and mean value of both attempts was calculated and taken as maximal range. Maximal range distance was credited with 70 scores whereas the system with the absolute maximal covered range was taken as reference system and credited maximum score. Percentage deviation of distance of other systems was analogously deducted as percentage of scores. If, for example, reference system had 100 m range, it was credited 70 scores. If a second system had only 50 m range, it would be credited 50% of maximum score, hence 35.

Comparison against ECG was conducted in a laboratory by using ECG tool Vicardio ECP-6 standard (Energy-Lab Technologies, Hamburg, Germany). Measurement was conducted two minutes at rest with single-polar extremity drains. Mean HRs of both ECG and relevant system were compared. A maximum score of 30 could be obtained at this test. A deviation of 1 beat per minute (bpm) was deducted with two scores. Only complete accordance of both values was credited with maximum score.

3. Results

3.1. Comparison of Hardware

Results for hardware are summarized in Table 2. A plus (+) is a positive feature a minus (−) is a negative one. If all systems were similar or identical, there is no separate classification. A plus/minus (±) indicates aspects which are both positive and negative. In context of the supplied hardware Acentas and Polar lead the field of monitor systems, both reaching 100 and 106 scores in sum for the hardware. The leading position of Polar depends on the storage capacity of the chest belt increasing data safety but also decreasing wearing performance which is indicated by the chest-belt questionnaire presented in Table 3. In case of wearing comfort, it has to be noted that both chest belts of Activio and Acentas were supplied by the identical manufacture. Both Polar and Acentas delivered high-quality receivers.

3.2. Comparison of Software

Results of software evaluation are summarized in Table 4. Again, similar to hardware evaluation, a plus (+) is a positive feature, and a minus (−) is a negative one. If all systems were similar or identical, there is no separate classification. A plus/minus (±) indicates aspects which are both positive and negative. Here, Activio offered the harmonious concept which led to the highest ranking. The installation procedure was easiest with the Acentas software, but Acentas did not focus on extensive statistical analysis. In this case, Polar as well as Activia provide a more developed software tool.

3.3. Measurement Results

As data of ECG comparison were only obtained with a single subject, they have to be regarded with caution. Further evaluation would be necessary to confirm or reject results. Data are represented against reference system. Acentas had 86 bpm average HR versus 88 of reference system. Suunto’s deviation was 80 to 85 bpm, Activio’s deviation was 81 to 85 bpm, and Polar’s deviation was 82 to 85 bpm, respectively. Score distribution is depicted in Table 5. Concerning distance measurement, same caution has to be taken as only one subject’s data were included in analysis. Nevertheless, Acentas gave reference with 349 m, followed by Activio with 141 m and Suunto with 107.5 m. It has to be noted that Activio’s system was supposed to reach 300 m. Last but not least, Polar reached 102 m which corresponded to the manufacturer information for this system. Nevertheless, all other systems had a wider range of data acquisition, and hence score distribution was credited as follows: Acentas 70, Activio 28, Suunto 21, and Polar 20.

Regarding failure quota, average downtime was 148 s (0,6%) for Acentas, 286 s (1,0%) for Polar, and 552 s (2,0%) for Activio. The Suunto system stood out negatively, as a complete data loss was seen. Single belts were recognised from time to time, but no consistent data acquisition could be accomplished. A receiver problem might have caused this failure. Therefore, Suunto was not scored at all in this test. Similarly, five out of ten Polar chest belts had signal loss and could not be reactivated whereas Activio managed 10 out of 10 signals, and for the Acentas system 9 out of 10 were used for data evaluation as one person was injured during match play. The summarized scores and overall results are represented in Table 5.

4. Discussion

The purpose of the present study was to compare four commercially available online heart rate monitoring systems and especially their use in everyday situation in team sports. The system of Polar could score especially with a clear design, useable features of the software, and a convincing product quality. Only Polar uses WLAN for data transmission and also adds a mobile terminal in pocket format which can easily be used outdoor and with bad weather conditions. But the high energy consumption of WLAN transmission would terminate the battery capacities and additionally the duration of measurement. The system of Activio has a functional and useful software and the instruction manual was very detailed and easily comprehensible. The price, however, was very high compared with the other systems. Acentas could score with a huge operating distance, a valid heart rate signal compared with ECG, a low failure quota, and an easy handling. In contrast, the system of Suunto had a total breakdown during competition measurements and could not be reactivated. So this system was evaluated as the worst. The evaluation of the several chest belts revealed no important advantage of one manufacturer. Only the chest belt of Polar showed weaknesses regarding wearing comfort. Altogether, all systems cannot be used for online heart rate monitoring. Prospectively, it would be a great challenge to realise online monitoring for swimmers, possibly leading to new opportunities for the training regime. In this context the system of Polar and Suunto had the advantage that data are also recorded on the chest belt memory during water immersion and could be evaluated after exercise.

Meanwhile, some of the tested heart rate monitoring systems are updated and upgraded with new functions, respectively. For example, Acentas included an offline memory in the chest belts and added a wrist monitor for direct heart rate analysis from up to twenty athletes by the coach.

In summary, Acentas system reached the best mark of all systems, but every system has its advantages and disadvantages depending on the using purpose, location, and weather. So this present comparative study cannot recommend a single system but rather shows strength and weakness of all systems and additionally can be used for further system improvements.

Disclosures

The investigators were responsible for the study design, data collection, data analysis, data interpretation, and submission of the paper for publication, independently of all funding sources. The authors declare that they have no financial conflict of interests to disclose with any of the companies named in this paper. There is no preferential order of companies in the paper.

Acknowledgment

The authors thank all manufactures for the delivery of evaluation systems with no charge.

References

  1. J. Achten and A. E. Jeukendrup, “Heart rate monitoring: applications and limitations,” Sports Medicine, vol. 33, no. 7, pp. 517–538, 2003. View at: Publisher Site | Google Scholar
  2. F. X. Gamelin, S. Berthoin, and L. Bosquet, “Validity of the polar S810 Heart rate monitor to measure R-R intervals at rest,” Medicine and Science in Sports and Exercise, vol. 38, no. 5, pp. 887–893, 2006. View at: Publisher Site | Google Scholar
  3. M. Kingsley, M. J. Lewis, and R. E. Marson, “Comparison of Polar 810s and an ambulatory ECG system for RR interval measurement during progressive exercise,” International Journal of Sports Medicine, vol. 26, no. 1, pp. 39–44, 2005. View at: Publisher Site | Google Scholar
  4. H. Kinnunen and I. Heikkila, “The timing accuracy of the Polar Vantage NV heart rate monitor,” Journal of sports sciences, vol. 16, p. 107, 1998. View at: Google Scholar
  5. L. Leger and M. Thivierge, “Heart rate monitors: validity, stability, and functionality,” Physician and Sportsmedicine, vol. 16, no. 5, pp. 143–148, 1988. View at: Google Scholar
  6. M. Thivierge and L. Leger, “The reliability of heart rate monitors,” Science and Sports, vol. 3, no. 3, pp. 211–221, 1988. View at: Google Scholar
  7. B. A. Lord and B. Parsell, “Measurement of pain in the prehospital setting using a visual analogue scale,” Prehospital and Disaster Medicine, vol. 18, no. 4, pp. 353–358, 2003. View at: Google Scholar

Copyright

Copyright © 2011 Martin Schönfelder et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Results

Spontaneous blink rates

Figure 1 shows the mean SBR (± SEM) over time with the stressor presented at the 10 min point and maintained thereafter for the duration of the experiment.

SBR over time for reactive and non-reactive horses. Mean SBR (SEM) (blinks min −1 ) for reactive and non-reactive horses (n = 33) during baseline (B) (minutes 1–10), initial treatment (IT) (minute 10, 1 min post-stressor presentation) and continued treatment (CT) (minutes 11–20 post-stressor presentation). P < 0.05 (*), P < 0.01 (**), P < 0.001 (***).

When partitioned into low (n = 16) and high (n = 17) reactive groups, the high reactive group showed a highly significant decrease in SBR during the IT period compared to baseline (11.1 ± 1.09 blinks per min to 6.2 ± 0.95 blinks per min, t1,30 = − 2.9, p = 0.008) and a significant increase in SBR from baseline during the CT period (11.1 ± 1.09 blinks per min to 15.6 ± 1.71 blinks per min, t1,30 = 2.7, p = 0.012). For the low reactive group, there was also a highly significant decrease in SBR during the IT compared to baseline, (11.4 ± 0.33 blinks per min to 5.8 ± 0.46 blinks per min, t1,32 = − 7.9, p < 0.001), but no significant difference in SBR during CT compared to baseline B (11.4 ± 0.33 blinks per min to 10.0 ± 0.67 blinks per min, t1,32 = − 1.9, p = 0.068).

Correlation of SBR with standard measures of stress

For all animals (low reactive and high reactive) combined, there was a highly significant moderate positive correlation between the change in SBR between baseline (B) and the continued treatment (CT) (ΔSBR) and change in cortisol (ΔCortisol) (r = 0.56, p < 0.001) (Fig. 2) and a highly significant strong negative correlation between ΔSBR and ΔRMSSD (r = − 0.63, p < 0.001) (Fig. 3).

Correlation of SBR with Cortisol. Correlation of change in SBR (B verses CT) against change in Cortisol (B verses CT) for all horses (low and high reactive n = 33) (r = 0.56, p < 0.001).

Correlation of SBR with RMSSD. Correlation of change in SBR (B verses CT) against change in RMSSD (B verses CT) for all horses (low and high reactive n = 33) (r = − 0.63, p < 0.001).

The HRV and cortisol results for each horse at each time-point can be found in Supplementary Table S1 online.


Heart Rate Monitoring on the Cheap November 12, 2013 1:53 PM Subscribe

Has she begun to seek IRB approval first? "Cheap" is rarely the first concern when dealing with physiological data. Her IRB will require her data collection and management and subject recruitment practices to fully anonymize, beyond recovery, the identity of each subject in relation to her data set, for example. Recruitment protocols are very likely to be limited to the standard method in her field.

However the standard method is usually "offer students 10 bucks." It is very difficult to recruit random strangers for free, and recruiting friends may be inappropriate for various reasons.

The other way this gets done is using someone else's existing dataset. But presumably the point is to correlate the heart rate data to some other input or condition. What is that? It matters a lot of it is, say, viewing pictures of attractive people or experiencing some form of induced stress.

This is, by the way, one reason doctoral dissertation advisers exist. Why is she asking strangers on a website (through you) and not her adviser about how to do this?
posted by spitbull at 2:06 PM on November 12, 2013 [2 favorites]

Oh, I didn't realize you meant "technically measure heart rates." The standard technique involves taking a pulse with a watch, which is free but requires training.

She could have subjects self report using the same iphone app. A lot depends on how standardized and accurate her actual research question requires the data to be. Again, adviser and IRB need to be consulted first. Make no assumptions. Pulse rate is personal medical information, governed by HIPPA regulations in some cases. Be careful.
posted by spitbull at 2:14 PM on November 12, 2013

How many people? Simultaneously or can a device be passed around? Monitoring for how long? Need long-term monitoring or short-term but high resolution data (HR over days or rapid changes over the course of tens of seconds)? 'accurately' means what here? In the lab, underwater or doing exercises?

ps: there are android and windows phone apps for this too (along with the ios one). $40 BP cuffs from your corner drug-store will also display HR. Amazon has over 1000 products from $24 upwards.
posted by Xhris at 2:17 PM on November 12, 2013 [1 favorite]

Response by poster: Thanks for your input so far everyone!

She is in the planning stage of her dissertation and will certainly get IRB approval before anything moves forward. However, she does not want to submit several different IRB applications, and in preparing a final IRB she needs to propose a specific apparatus.

Here's that additional info:

- Only one person at one time needs to be recorded. The device will need to be able to capture data for at least 100 persons, but only one device is needed.

- The task is a stress test and the individual will not be anticipating experiencing a challenging situation. Therefore, the participant should (ideally) not be able to see their heart rate at any time. However, their data should be able to be easily recorded and transmitted to use in subsequent analyses.

- The participant's heart rate needs to be recorded for at least 40 minutes, and she needs continuous data throughout the task. Specifically peak reaction (or lack thereof) to challenge and time it takes to return to baseline heart rate are the two variables of interest.

- The research questions involve physiological reactivity and self-regulation in response to an unanticipated challenge (similar to the Trier Social Stress test).

She has looked into heart rate watches and bands, but is unsure if these would be most appropriate outside of an exercise paradigm. Might they not be sensitive enough?

And of course she needs to ideally use something that isn't too new technology (to scare the IRB away) but is still pretty cheap.

Thanks everyone!
posted by zscore at 2:43 PM on November 12, 2013

Response by poster: Thanks for the input all.

It seems like she's done her homework and unfortunately, it seems like almost all the research in this area in psychology (which is relatively new to psychology) is done with pretty expensive equipment setups (Mindware Technologies/BioLab). My friend is familiar with this equipment, knows how to use it, but does not have access to it.

The closest anyone has come seems to be Actiwave Cardio from Camntech http://camntech.com/products/actiwave-cardio/actiwave-cardio-overview
but it costs $3,000 per pack.

She wants to bring some novel ideas perhaps from other disciplines to her advisor/program and think creatively about how to get her dissertation work done on a budget (

if anyone out there knows of any specific studies/justification/feasibility for monitoring heart rate using consumer-level heart rate watches or other inexpensive technology that would be most useful.
posted by zscore at 3:13 PM on November 12, 2013

Perhaps Polar makes one that will provide your friend with this data? http://www.polar.com/us-en/products Surely one of the heart rate monitors out there meant for athletes would have a feature that would cover a 40 minute stretch and download to a computer.

I have a $40 Polar heart rate monitor for running and it works great for me. I think mine just tells me the current heart rate, though, and does not store anything. An more expensive heart rate monitor might do more (but not be too expensive for the intended purpose).
posted by AllieTessKipp at 3:37 PM on November 12, 2013

Will the test subjects have their hands free? If so, you could use this hand held monitor. The school could already have the appropriate data logging software ("LoggerPro")- I've used it in chemistry and geology classes, so far (for temperature probes, pH probes, etc.)

As a result of a grant or Vernier promotion or something, there's a full set of sensors in one of my geology labs, including some of the more medical probes. If this probe sounds like it would work, she should start asking around some of the science departments and see if there's one stashed someplace random.
posted by Secretariat at 5:45 PM on November 12, 2013

Best answer: I have two options to suggest:

1- Get a sport watch that pairs with an around-the-chest heart rate monitor. For example, the Garmin Forerunner series can record HR for several hours with no problem. You complete each “workout” between participants then when the session is complete, upload to Garmin Connect website. From there, you will be able to export the HR results as a CSV file and import in Excel.

One possible advantage is that you only need to have the watch within a range of 6-8 feet during the experiment, or have them wear it with the watch face taped over. The participants can then get up and move around, not only stay seated and pluged into a computer.

2- If you want to skip the sports watch and record to the computer directly, you would need software such as SportTracks with the Live Recording and HRV plugin (Shareware/Paid plugin). I have not used it before but looks like it would do the job. You would need a Garmin USB ANT+ Stick (

50$) for the computer to receive the data and an Ant+ Heart Rate Monitor (

Best option would be to buy the Garmin FR70 for 130$. It comes with the watch, the HR monitor strap and the USB receiver. That way you have all the equipment needed to try out both solutions for not a lot of money. I use Garmin as an example here because it is what I use and know but Polar and other brands can probably do the same.

In all cases, if she uses a heart rate monitor that contacts the skin directly, investing in a tube of electrode gel (5$) will ensure consistent results with no drop outs. It is what doctors use during actual medial test to ensure proper contact.
posted by TinTitan at 8:43 AM on November 13, 2013

Best answer: From a perspective of an athlete who has used heart rate measurement, there are several different things meant by "heart rate". Most of the time it just means beats per minute. This is the easiest thing to catalog and there are affordable tools for doing this.

The more complicated side of the house is analyzing the stroke itself. For this you find EKG and heart rate variability tools. These are used to measure stress levels. Athletes use HRV in particular to identify patterns that indicate over training. There are some new tools that are much more affordable in this area now.

If she needs the medical grade devices I wonder if it might be possible to contact the manufacturers and make a strong case for buying one at a discount. They might have a refurb model or they may just feel generous.
posted by dgran at 11:46 AM on November 13, 2013

Best answer: This device should be up to the job and it is very inexpensive: Bitalino

Might require some programming!
posted by benign at 6:18 PM on November 13, 2013



Comments:

  1. Joy

    It should be said that you are wrong.

  2. Alhhard

    Yes you are a talented person

  3. Dora

    What words ... Super, great idea



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