By Lisa Newman

Heart Rate Variability (HRV) is a measurement of overall wellbeing. In fact, it is sometimes touted as the best available single measurement of health. Tracking HRV can help you tune into your body, build resilience, avoid overtraining, and prevent burnout.

Specifically, HRV measures the variability of the time between your heartbeats. Greater variability between heartbeats equals more flexibility and greater physical and emotional resiliency. This is based on research showing that heart rate variability reliably predicts whether you are in a state of physiologic stress or not. It’s the basis for the popular Heart Math program, and other programs you may have heard about that monitor stress levels and athletic performance potential.

What’s cool is that in the recent past the evaluation of HRV took many thousands of dollars of equipment and was only able to be carried out in advanced medical settings. Now you can get the same and even better information using your smart phone.

The easiest way to get started monitoring HRV is to use one of the popular apps such as Welltory or Elite HRV. (Note: I am certified in the Foundations of Heart Rate Variability by Elite HRV.) These are free from your app store although more advanced features require a subscription. Be aware that HRV measurements taken by fitness tracking watches or jewelry are not proven to be accurate and are not recommended. However more recent research has approved the Apple watch as an accurate device and it’s now integrated into the Welltory app, and can be activated with the Breathe function.

To take an HRV measurement place your finger over the rear camera of your smart phone after indicating in the app that you want to take a measurement. Use of a heart rate monitor around your chest or finger will increase the accuracy of some of the advanced measurements but it’s not necessary.

The primary measurement we want to track is a single number which is often converted to a scale of 1 – 100 and reported as your HRV. (This is actually the RMSSD or square root of the mean of the squared differences between successive RR intervals.) Different apps present this differently and may provide analysis rather than a single number. I’ve found the Elite HRV app is best for straight forward simplified tracking and the Welltory app is best if you want analysis and insights.

A higher number is generally better, but beware that you can only compare against yourself, and only after establishing a baseline for a minimum of two weeks. HRV naturally reduces with age so a healthy 50 year old may have lower HRV scores than an average 20 year old. Also different apps and measuring devices use different scales and formulas. What matters is variation from what is normal for you.

Best practice is to take a morning readiness measurement. While there are reasons to take standing or sitting measurements I recommend laying down with your head propped on a pillow while breathing normally for two minutes. Be sure you use the same position daily.

Pay attention only to the Time Domain parameters. Measures of Frequency Domain parameters requires a five minute measurement periods and a more accurate measuring device.

It’s very important to pay attention to how you are feeling internally at each measurement. This will help you gain body wisdom. It’s also important that you rely on your own internal perception as the most accurate measure regardless of what your HRV result is. This is the same advice as for other tracked measures such as sleep quality, numbers on the scale, steps taken, or calories (supposedly) burned. Don’t let numbers that contradict your internal wisdom determine how you feel or behave. These apps and measuring devices have limitations and are only one indicator of health.

Finally, don’t freak out if the app reports that you are often in high stress or that your parasympathetic (relaxation state) is consistently low. This is common in women, but particularly common in those with a history of eating and body issues or with past trauma.

You can find more in-depth information about HRV in this article.