Micro-fluctuations in the time between heartbeats are proving a helpful indicator of mental health, stress levels, exercise capacity and even how well you are ageing.

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 ...

Most fitness trackers offer a wealth of heart-rate data. Here’s how to make sense of it. By Talya Minsberg If you wear a smartwatch or fitness tracker, you likely already have access to a steady ...

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 ...

Scientists have discovered that exercise remodels the heart's nerves and changes how it regulates its heartbeat and responds to stress.

Wearable technology provides athletes with a constant stream of metrics like heart rate variability and recovery, often synthesized by A.I. into real-time training recommendations. But this dependence ...