We’re familiar with two popular measurements, heart rate and blood pressure, to indicate the health of an individual. In both of these cases, lower is better with respect to overall health.
Another measurement called heart rate variability (HRV) is getting the attention of fitness experts. This is the variability in the length of time between your heart beats. For example, if you have a resting heart rate of 60, your heart doesn’t simply beat once per second. Rather there are millisecond variations between beats and this is what HRV measures.
Why is HRV important?
HRV is a way to assess how well an individual handles stress. Unlike heart rate and blood pressure, a higher number is seen as healthier. Think of HRV like a basketball player. A highly competent player has the ability to jump, pivot, dodge, dribble and run on the court. They easily adapt to the situation at hand. HRV works in a similar way. It measures how easily your body can move between the sympathetic nervous system (fight-or-flight) and the parasympathetic nervous system (relaxation response). A higher number indicates a greater ability to move easily between the two.
You can find charts on the Internet touting ideal HRV ranges, but note that there is no ideal number. Instead, each individual has an HRV that is normal for them, and this can be affected by age, hormones, activity level and gender. It’s more valuable to see how your HRV changes over time vs. compare yourself to others.
Is HRV a new type of health indicator?
HRV has been studied for decades. For example, it was cited back in the 1994 Framingham Heart Study. It’s a measurement that your physician may take in conjunction with an EKG. It is getting increased attention in the fitness world now because smart watches such as Apple, Garmin, and Fitbit have the ability to capture it. Note that the accuracy of these devices is not yet proven, in part because they take measurements from your wrist vs. the more reliable chest strap heart monitor.
How do you improve HRV?
One of the best ways to improve HRV is to simply stop doing anything for a minute and just take some long, slow breaths. This was the biggest take-away for me when I did this research. I have an Apple Watch with a Breathe app that prompts me to do this deep-breathing and I thought it was pretty silly. After all, who would just want to sit there and breathe when you could be doing something? I tried the app because Apple said it would make the HRV more accurate. What I discovered instead was the value of being still for just 60 seconds – and how rare that is for most of us.
The top take-away is this: while HRV is an interesting measurement, it’s more important to look at how we’re actually dealing with stress. One of the best ways to do this is to take a minute or two each day to stop and simply breathe.
