Our newest trait release “Resting heart rate and HRV” looks at gene variants that may be linked to a higher resting heart rate and lower heart rate variability. Looking at your results may have you wondering how you can measure your heart rate variability. Read on to find out. 

What is heart rate variability?

Heart rate variability is the variation in time between each consecutive heartbeat. To put this into perspective, if you had a heart rate of 60 bpm, your heart wouldn’t beat exactly every second, it may be at 0.9 secs, then 1.4 secs, then 2.1 and so on. 

Heart rate variability reflects the regulation of autonomic balance (between the parasympathetic and sympathetic nervous systems) to maintain heart rate and blood pressure. The parasympathetic nervous system normally acts to slow down heart rate and increase heart rate variability whereas the sympathetic nervous system increases heart rate and reduces heart rate variability. Heart rate variability also reflects the heart's ability to adapt and respond to changing circumstances and unpredictable stimuli, for example during exercise. 

Having decreased heart rate variability is thought to be related to unfavourable outcomes in disease states and is also associated with fatigue, stress and burnout with athletic performance. By contrast, higher heart rate variability suggests greater aerobic fitness and better overall health. Following your personal recommendations highlighted in the trait can help to improve your heart rate variability and contribute to healthy cardiac function. 

Measuring heart rate variability

There are several complex methods that are used to evaluate heart rate variability. The most common measure is through an electrocardiogram (ECG), which records your heart’s rhythm and electrical activity. Multi-lead ECG systems are the gold standard, however, they aren’t easily accessible and are usually used in a medical setting. 

Other methods you can use to monitor your heart rate variability are wearable devices. Although these won’t be quite as accurate, they are a lot more accessible. The most accurate wearable device is the chest strap, which uses ECG electrodes to measure your heart rate variability. 

You can also use your smartwatch to measure your heart rate variability. Watches provide heart rate estimates from the pulse signal recorded at the wrist. They are based on a technique called photoplethysmography (PPG), which uses light and a photodetector on the surface of the skin to measure changes in blood flow that accompany each heartbeat. 

Measuring heart rate 

While it’s not particularly easy to measure your heart rate variability, you can measure your resting heart rate and use this to track athletic progress. As you train more regularly your heart becomes stronger, this allows blood to be pumped around the body more efficiently and will lead to a reduction in heart rate.

To measure your resting heart rate, place your index and middle fingers on the opposite wrist just below the base of the thumb. You can count how many times your heart beats for 15 seconds and multiply by 4 to get your beats per minute, or, for greater accuracy, you can count for the whole 60 seconds.

Your resting heart rate should be between 60 and 100 beats per minute, however, this may be lower if you are regularly exercising. Having a lower resting heart rate is a positive training adaptation that occurs as the heart becomes more efficient at pumping blood around the body, so doesn’t have to work as hard. It is common for trained athletes to have resting heart rates of around 40 bpm. 

References 

Acharya, U.R., Joseph, K.P., Lannathal, N., Lim, C.M., & Suri, J.S. (2006). Heart rate variability: a review. Medical and Biological Engineering and Computing. 44: 1031-1051.

Altini, M., Plews, D. (2021). What is Behind Chances in Resting Heart Rate and Heart Rate Variability? A Large-Scale Analysis of Longitudinal Measurements Acquired in Free-Living. Sensors. 21, (23).

Castaneda, D., Esparza, A., Soltanpur, C., & Nazeran, H. (2019). A review on wearable photoplethysmography sensors and their potential future applications. International Journal of Biosensors & Bioelectronics. 4, (4), 195-202. 

Dong, J. (2016) The role of heart rate variability in sports physiology (Review). Experimental and Therapeutic Medicine. 11, 1531-1536.

Draghici, A.E., & Taylor, A.J. (2016). The physiological basis and measurement of heart rate variability in humans. Journal of Physiological Anthropology. 35, (22), 1-8.

Georgiou, K., Larentzakis, A.V., Khamis, N.N., Alsuhaibani, G.I., Alaska, Y.A., & Giallafos, E.J. (2018). Can Wearable Devices Accurately Measure Heart Rate Variability? A Systematic Review. Folia Medica. 60, (1), 7-20.

Hernando, D., Roca, S., Sancho, J., Alesanco, A., & Bailón, R. (2018). Validation of the Apple Watch for Heart Rate Variability Measurements during Relax and Mental Stress in Healthy Subjects. Sensors. 18, (8).

Hinde, K., White, G., & Armstrong, N. (2021). Wearable Devices Suitable for Monitoring Twenty Four Hour Heart Rate Variability in Military Populations. Folia medica, 60, (1), 7-20.

Sattar, Y., & Chhabra, L. (2022). Electrocardiogram. Electrocardiogram. In StatPearls [Internet]. StatPearls Publishing.

Shaffer, F., & Ginsberg, J.P. (2017). An Overview of Heart Rate Variability Metrics and Norms. Frontiers in Public Health. 5, 258.