What if we could take one simple self-administered test every day that would tell us our overall health and fitness level? And what if, based on the results of that test, we could adjust our daily routine including exercise, recovery and sleep patterns to achieve the best possible outcome for our personal well-being each day?
It goes without saying this would be a medical breakthrough, following in the trend of self-diagnosis where more and more people are taking charge of their daily health rather than leaving the responsibility solely to their physician. Heart rate variability (HRV), or the variation in the intervals between heart beats, is the one biomarker that shows promise as being a broad indicator of overall health and fitness. Physicians and trainers have relied on HRV for decades because beat-to-beat heart rate micro-patterns reveal the real-time state of our autonomic nervous system which controls both our physical and emotional well-being. HRV is a measurement of the body’s internal balance (homeostasis). Now HRV is emerging as an accessible tool for us to use on our own in our daily lives.
To describe HRV, and in contrast from what we know regarding traditional heart rate measurements, one must realize that the greater variability in the time gap between heart beats indicates a healthy, fit, well¬-rested heart. Elevating your average HRV values over time is indicative of improved cardiovascular fitness. A low HRV value (a heart beating closer to a fixed rhythm) is believed to be an indication of a poorly functioning heart–perhaps an over-trained athlete or a person who is unfit, overstressed, or has developed cardiac disease risk factors. Examples of both high HRV and low HRV measurements are illustrated in Figure 1 below. By tracking HRV regularly, one can establish a baseline value and then be alerted to excessive stress or insufficient recovery when HRV readings are lower than normal.