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 ...

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 ...

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 ...

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 ...

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 ...

DEAR MAYO CLINIC: When I go for a walk or to the gym, people always seem to be checking their pulse, whether by hand or with a wearable. Why is heart rate so important? ANSWER: Your heart rate, or ...