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

Add Yahoo as a preferred source to see more of our stories on Google. You know the feeling. When you first see your crush and your head starts spinning, your palms ...

You're curled up on the couch, finally relaxing after a long day when suddenly, your heart starts racing. You're obviously not exercising and you don't think you're stressed, so why does it feel like ...

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 ...