Heart rate variability is one of the main things your smartwatch or fitness tracker measures. Here's what it means.

While certain health metrics such as your resting heart rate or cholesterol levels may change over time, age alone doesn’t provide a complete picture of your wellbeing. For example, you might assume a ...

It’s been known for decades that heart rate variability (HRV) during labor signals how a fetus is responding to stress. Lower HRV—a lower variation in heartbeats—is even a risk factor for sudden ...

People with rheumatoid arthritis (RA) who experienced disease flares often showed changes in heart rate and physical activity ...

New research, presented today at the European Academy of Neurology (EAN) Congress 2025, has uncovered a powerful link between nighttime heart rhythm and future health conditions, even in people with ...

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 ...