Learn why your heartbeat races after climbing stairs. A cardiologist explains what's normal, the impact of lifestyle, and when to seek medical advice.

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 ...

Many people find themselves lying in bed, suddenly aware of their heart beating faster than usual. When the room grows still, the pulse in your chest can feel louder, stronger and impossible to ignore ...

The human heart works quietly in the background, beating around 100,000 times a day. Most people notice it only during exercise, stress, or illness. Yet doctors say one simple number, the resting ...

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 ...