A person’s heart rate variability refers to the way in which their heart changes its rhythm with each beat. A higher number indicates resilience and longevity, while a lower number shows the body ...

Here’s everything you need to know about heart rate variability and why it’s so complicated—plus how doing a deep dive into yours could potentially help improve your performance. You know ...

They also found that metrics such as root mean square of successive differences (RMSSD), used for calculating heart rate variability, requires sampling rates greater than 64 Hz, the nominal ...