If you wear a fitness tracker, you've likely seen a stat labeled "HRV" pop up on your screen. But what does it mean, and does it matter? Short for heart rate variability, HRV has become a popular ...

Even mild dehydration can negatively affect your brain functioning and attention span, so it could be holding you back at work and getting in the way of your goals. Drinking a glass of water could ...

A recent study showed that the heart rate variability of a dog and its owner adapt to each other during interaction. High heart rate variability is associated with relaxation, while low heart rate ...