Electrodermal activity measurement shows athletes new information

Different kinds of physiological measurement systems have been used for a long time in top sports. Wearable devices have made exercise tracking easy for everyone.

Heart rate monitoring is the most used measurement in sports. It was developed by an Australian physician Robert Treffene for swim exercising. In Finland hear rate monitor was invented by the Polar Electro founder, professor Seppo Säynäjäkangas in 1975.

Today there is a huge variety of equipment for hear rate monitoring. The most accurate ones still measure from chest, either with a band or with taped sensors. Wrist worn trackers are comfortable to wear and they have largely displaced chest bands especially with non-professional exercisers. The accuracy of wrist worn trackers has been improved in past years, but it suffers especially at high heart rates.

Heart rate, heart rate variability (HRV) and electrodermal activity (EDA)

Analysing heart rate gives a good view of physical strain. With different algorithms it is possible to understands also recovery, sleep and stress.

Heart rate variability (HRV) has been lately brought up especially in measuring non-physical load. There are challenges, as at high heart rates the algorithms struggle to understand what happens: is the person physically at rest, but nervous (e.g. about a soon-to-start exam), or is it now about physical exercise? Here the accelerometers, present in all of the trackers, are of help. These components can detect whether a person is moving or is at rest, and much more about movement directions and pace.

The electrodermal activity (EDA) measurement brings interesting new information to analyse performance of an athlete. This does not tell about heart, but about sympathetic nervous system activation through sweat gland reactions of skin. Skin is the only organ that is purely innervated by the sympathetic nervous system. The EDA measurement is very sensitive to emotional and cognitive stress, and it has been used in psychological research already for over 100 years. Only lately it has become available for consumers.

The Moodmetric smart ring measures electrodermal activity. The ring is comfortable to wear and it is thus well suited for continuous, long term measurement. Only a sufficiently long measurement period gives a full picture on stress, how it is generated and how recovery happens during weeks, months and even years.

Both top sports, and going after personal goals in exercising benefit of stress load related information. It is good to understand what sources of stress or recovery might affect the performance. For instance, cognitive load of a professional athlete might be less than for someone who need to have a day job to finance the sports career. The professional athlete can probably exercise more, as there is more time for recovery. The results and performance are affected by emotional and cognitive load, if there is no time to unwind.

Read more: Moodmetric-measurement in research

Moodmetric will participate SMASH-sports event in Helsinki the 28-29th November, come to meet us and test the smart ring!

Contact:
Niina Venho
[email protected]
+358 40 710 4087

My discovery: I am more stressed at home than at work

Guest post by @amyskogberg

Surely I have read about studies saying that women’s stress levels rise when they go home after work to take on the household work, but I didn’t think it concerned me. My work is quite demanding and involves constant change, high tempo and big variation in work tasks, and therefore I have always thought that the greatest stress hits me at work and not at home.

However, now I am proven the opposite, after testing the Moodmetric ring for two weeks.

The Finnish Moodmetric ring tracks your stress levels. By sensoring the skin conductance, the ring measures the body’s ability to conduct electricity – when you stress, your sweat glands activate and your skin conducts more electricity.

The user downloads the data to the Moodmetric app and gets an overview of how the stress levels have fluctuated during the day. This was really interesting to follow!

During the two weeks I made three fascinating observations. The first was that my stress levels reached the highest peak as I entered home. And I do understand why. “Hi mom, nice to have you home, I have a math test tomorrow and I need your help”. “Hi mom, good that you’re home, this form needs to be filled in, and I was supposed to return it already yesterday”. “Hello dear, so nice to have you home, I’m starving..!”

The second observation was that my stress levels were the lowest every time I reached the so called flow state. When fully concentrated on my work, the stress levels sank significantly.

This is in line with what research has concluded about physiological reactions during the flow state; breathing becomes slower and deeper and resembles a meditating person’s breathing.

The third insight was about recovery.

The ring cannot differentiate between positive and negative stress, because the body reacts equally when engaged or eager as when stressed or worried. Regardless, the body still needs to recover.

I am lucky to be able to sleep well, so I usually get enough rest through sleep. However, there were also days when I did not get my stress and recovery in balance. I realized that I need to be aware of this and pay attention to getting enough recovery, for example through meditation or mindfulness exercises to unwind after an intense day.

So what can we learn from this?

  1. It is really important to learn to know your own sources of stress. What causes the most stress in your life? Can you avoid or change those situations? Maybe ask the children to wait for half an hour after you come home before responding to their wishes so that you can relax with a cup of coffee and the daily newspaper?
  2. Try to find out how you can get into the state of flowand schedule time for those things in your life. For me for example reading a good book, writing or sewing will do the trick.
  3. Make sure you get enough recovery. Stress is not dangerous if you make sure you rest well. If you go into overdrive at times, even if it feels good, you have to unwind afterwards. Otherwise positive stress may develop into negative stress.

The first step to reducing and preventing harmful stress is to understand the mechanisms, both internal and external, that trigger your stress reactions. For this, I highly recommend the Moodmetric ring. It is a simple and well-functioning way to learn more about what causes stress in your life.

Some examples of my Moodmetric data: On the left is the diagram of a day when I wrote content for a marketing campaign in a flow state.  On the right a day when I was being creative and had my head full of ideas.

 

Amy Skogberg is a mental trainer, motivational speaker and marketing manager

Read the original blog post in Swedish here

Moodmetric data analytics tool

The Moodmetric data analytics tool is created to support research and development projects related to EDA (electrodermal activity) measurements.

The tool enables researchers and developers to quickly process and visualize large Moodmetric data sets in uniform manner. It generates both group and individual level reports based on input data from wearable devices. The tool is released as open source for anyone to benefit of the Moodmetric measurement data in various use cases.

Download the Moodmetric data visualization tool instruction here.

For more information, contact
Jari Jussila
[email protected]
+358 40 717 8345

Moodmetric brings stress measurement to Smart Office

 

The Moodmetric ring collects stress and recovery information in smart spaces in a pilot project starting in February 2017. The real time stress data will be combined to a Smart Office concept by Polku Innovations.

The outcome will be a brand new service where there will be a measurable link between wellbeing of the employees and the space they are working in. The data collected by the Moodmetric smart ring will be combined to a platform by Polku Innovations. This gives the companies unique opportunities to understand how the environment affects the employees and their work.

Polku Innovations develops and offers their customers measurement and data analytics services to a smart office. Their concept uses sensors to collects information such as temperature, humidity, air pressure, light intensity, noise and utilization rate of the space. Data is used to facilitate the daily work and enhance wellbeing.

 

Electrodermal activity measured by the Moodmetric ring

Electrodermal activity

With any sympathetic nervous system activation, skin reacts and becomes a better conductor of electricity. This can result from emotional, cognitive or other psychological origin. The phenomenon is known as electrodermal activity (EDA) and it is widely adopted in psychological research (1). Other commonly used terms for this phenomenon are skin conductance response and galvanic skin response.

EDA is generated by the activity of the sweat glands.  Moodmetric measures the palmar skin on your finger. The palmar skin is the recommended EDA measurement location, since it has the highest eccrine sweat gland density (2). You can measure EDA elsewhere as well but the reliability is not as high or as easily achieved.

The unconscious actions of the human body are regulated by the autonomic nervous system. It consists of the sympathetic part and the parasympathetic part. The parasympathetic part controls the body’s rest-and-digest functions and the sympathetic part controls the fight-or-flight reactions. With EDA, we can examine the latter.

The sweat glands are exclusively innervated by the sympathetic nervous system. This makes EDA an ideal measure for sympathetic activation (2). Electrodermal activity correlates to general cognitive and emotional intensity, and high responses are caused by e.e. stress, enthusiasm, anxiety, joy, anger (1, 3).

Mobile EDA devices have been used by scientists for some time (2, 4). The Moodmetric ring is an unobtrusive option to follow EDA responses real-time and in long term.

Signal accuracy

The signal accuracy has been proven in a study of 24 people by the Finnish Institute of Occupational Health by J. Torniainen et al.. The accuracy against a laboratory grade reference was found to be 83 %. They conclude:

“Clearly the ring sensor can be used to measure a valid EDA signal as indicated by the similarity of both event-related responses and the calculated features. The accuracy of the Moodmetric EDA Ring is adequate for psychological and physiological research when weighted against the advantage of conducting ecologically valid experiments outside laboratory conditions.”

The results were accepted for publication in the 2015 conference of the IEEE Engineering in Medicine and Biology Society (EMBC 2015, August 25-29).

The Moodmetric measurement has also been proven to be accurate by THe University of Tampere, Finland. The correlation with the reference equipment Nexus-10-MK II was good. Comparison details in charts below.

With skin conductance level (SCL) we refer here to raw measured skin conductance without any filtering. The figures below show the comparison of the two devices. 

References

1 Mendes, W.B. (2009). Assessing the autonomic nervous system. In: Harmon-Jones   E. ja Beer J.S. Methods in social neuroscience. New York: Guilford Press. p. 118-147.

2 Setz C., Arnrich B., Schumm J. and La R. (2010) Discriminating Stress From Cognitive Load Using a Wearable EDA Device. IEEE Trans. Inf. Technol. Biomed. 14(2). p. 410-417.

3 Nikula R. (1991) Psychological correlates of nonspecific skin conductance responses. Psychophysiology. 28(1). p.86-90.

4 Poh M.Z, Swenson N.C. and Picard R.W. (2010) A Wearable Sensor for Unobtrusive, Long-Term Assessment of Electrodermal Activity. IEEE Trans. Biomed. Eng. 57(4). p. 1243-1252.

 

 

Moodmetric and quantified inner state

Guest post by Matti Nelimarkka

 

Before Christmas, I took part in research where I read news and my emotional state was monitored via Moodmetric. Thus, it was rather classical in the field-study, trying to validate if the technology and data analysis strategy can be used outside laboratories too. I’m waiting to hear the results, the challenge with psychophysiological measurements is noisiness, and doing the measurements when I’m under blanket or riding the bus should just generate more noise. But science aside, let’s speak my experience.

image

Once monitored, humans are often more conscious about their activities. I know this as the new effect but different fields approach this naturally using their own terminology for this well phenomena. What this meant for me was a rather weird experience of higher than normal ambiguity or unsureness about my own feelings. First, the need to label my emotions as well as being measured on those might have lead to social conformity; the need to report and feel the experiences one might experience.

More interestingly, towards the end I had difficulty to acknowledge my emotions. Naturally, Finnish news might not be the most interesting and emotion triggering material out there, but I think it wasn’t just about this. Instead, I believe that the knowledge of “scientific” measurements and my trust towards technology lead to the question: should the machine already know what I’m experiencing, why am I part of the loop here? I tried to outsource the interpretation of my emotional state to the magical ring, instead of asking myself these questions. Considering how vital part of humanity emotions are, it is somewhat worrying that I rather voluntarily left the task to the machine ands begs for me the question, at what point I’m no longer capable of understanding myself due to trusting these technologies too much?

Well, moving away from this type of autobiography to see what academia is saying on this. Unfortunately, I’m more familiar with the empirical work even while the real question here is more philosophical. Study on the feedback loops of psychophysiological adaptive system have recently gained some attraction in academia. Snyder et al (2015). studied both individual and group work situations aiming to support mindfulness through an adaptive psychophysiological system, MoodLight. They observed participants feeling somewhat weird after a system presented their internal state to them, but also trusted the output of the system:

For example, one participant felt that she was highly aroused, “stressed” in her words, although the output of the lights was a steady blue-violet. Rather than questioning the accuracy of the reading, she concluded, “I guess I’ve gotten better at not being totally enraged.”

In group situation, participants explained how they were not sure who is affecting the output in the end. Thus, based on my experiences and a super-shallow academic reading we can acknowledge the interesting effect these tools have in everyday life, even the awkwardness related to constant self-monitoring. Maybe an interesting design challenge would be considering how we relate to these technologies, more specially how we ensure that people still are sure of their own inner state – no matter what the sensors think.

Cross posted from Science & Industry