What is heart rate variability (HRV)? As popular as the metaphor may be, a healthy heart doesn’t beat as regularly as a metronome. In fact, it changes its rhythm with each beat. Heart rate variability ...

Heart rate variability isn’t just for elite cyclists—find out how tracking HRV can benefit every rider’s training, recovery, ...

People with long COVID often report fatigue and other symptoms that make it challenging for them to enjoy life like they once ...

Fitness trackers and smart watches are widely popular wearable devices that measure several types of health metrics, including step count, calories burned, sleep quality, Vo2 max and heart rate. As a ...

These days, it may seem like there’s a million different data points that you’re supposed to keep track of—hello, steps, sleep, and recovery scores!—and it’s difficult to know which ones are worth ...

With a Whoop health tracker strapped to my wrist for the past year, I’ve had an unusually detailed window into my biology – sleep, blood oxygen, steps and, most intriguingly, heart rate variability, ...