An out-of-sync heartbeat can have dangerous health consequences. But exercise may offer a prevention method.

Cardiovascular exercise like running or walking has a number of health benefits. But too much exercise may be unhealthy, especially after a heart attack.

Exercise is a crucial part of a healthy lifestyle. But for some people, it appears there is such thing as too much exercise.

The hearts of people with atrial fibrillation beat too fast, which can cause serious and sometimes life-threatening problems. Weight loss might help some patients correct that heartbeat.

Many people who have implantable defibrillators to treat their irregular heartbeats are advised to take it easy when it comes to sports, but this recommendation may be overly cautious.