The heart is the body's hardest-working muscle. Whether you're awake or asleep, or exercising or resting, your heart is always at work. It pumps blood through arteries to deliver oxygen to organs and ...

A fast heartbeat can be caused by emotions like stress or anxiety. Dehydration, or drinking caffeine or other stimulants, can ...

Forget the myth that exercise uses up your heartbeats. New Australian research shows fitter people use far fewer total heartbeats per day - potentially adding years to their lives. Athletes had an ...