The SCIENCE BEHIND Your HEARTBEAT

Your pulse reflects everything from your fitness level to chronic stress-and shifts from your baseline can signal that it's time to pay attention.

- by LISA MULCAHY

How often do you think about your heartbeat?

Probably not regularly, unless you notice it when you are working out or anxious. But the truth is that you should probably be paying it more mind.

“Your heartbeat is a window into your cardiovascular health,” says Sotirios Nedios, M.D., Ph.D., an electrophysiologist in the Heart Center at the University of Leipzig in Saxony, Germany, and a member of the American College of Cardiology’s Electrophysiology Section Council.

“A normal resting heart rate for adults typically ranges from 60 to 80 beats per minute, or bpm. A consistently elevated heart rate above 80 to 90 bpm, though considered within the normal range, has been associated with increased cardiovascular risk.”

A faster heartbeat isn’t necessarily dangerous, though. “What's most important is knowing your baseline,” Dr. Nedios explains. “If your usual resting heart rate is around 65 bpm, and it suddenly increases to 90 to 100 bpm without an obvious cause, this warrants attention.”

Beyond that, a few other things about your heartbeat are helpful to be aware of, such as how your lifestyle can influence it and the clues it can provide about your health. The more you know, the better you can take care of your heart.

Heart Smarts

Your heartbeat is the contraction of your heart as it pumps blood through your lungs and body, powering all your functions. If you listen closely, it sounds like “lub-dub.” The “lub” sound happens after the atria in the heart pumps blood into its ventricles, while the valves are closing. The “dub” sound happens after blood is pumped away from the heart, as the aortic and pulmonary valves in it close.

If your heart beats too fast (more than 100 bpm when you are at rest), that’s called tachycardia. If it beats too slowly (less than 60 bpm when you are at rest), that’s bradycardia. Interestingly, women tend to have faster heartbeats than men do.