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 heart that beats too fast can leave you lightheaded, dizzy, out of breath or feeling fatigued.

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 ...

Cardiovascular exercise, also called cardio or aerobic exercise, keeps you and your heart healthy. This specific type of exercise gets your heart rate up and your heart beating faster for several ...

Sitting quietly at your desk, watching TV, or lying in bed at night, your heart should be taking it easy – beating steadily and calmly at somewhere between 60 and 80 beats per minute for most healthy ...