Add Yahoo as a preferred source to see more of our stories on Google. Electrocardiograms, or ECGs, record the electrical activity of your heart. Randy Faris/The Image Bank via Getty Images Your ...

If you recently got a pacemaker due to an arrhythmia (an irregular heartbeat), heart failure, or bradycardia (a heart that beats too slowly), you might have concerns about getting back into exercise.

A pacemaker is a small, battery-powered device that controls the heartbeat. Our heartbeats are controlled by a highly efficient, biological electrical system that ensures our heart steadily pumps ...

Your heart's job is to keep your pulse steady to pump blood throughout your body. Sometimes your heart rate is slower when you're relaxing, and sometimes it's faster when you're exercising or stressed ...