The Truth About Heart Rate and Exercise

If you're even a semi-serious exerciser, you've probably read or heard that it's a good idea to know your resting and maximum heart rates and to track your heart rate during workouts.

Well, yes and no.

Knowing how fast the heart is beating before, during, and after exercise can be helpful for some people, including heart patients and competitive athletes. But experts tell WebMD that much of the conventional wisdom about heart rate and exercise is wrong.

Take this quiz to separate fact from fiction about heart rate and exercise.

1. TRUE OR FALSE: It's vital to monitor your heart rate during exercise.

FALSE. It all depends on who you are and why you're exercising.

If you have heart disease and your doctor has forbidden you to exercise strenuously, monitoring your heart rate during workouts is a good way to avoid pushing your heart into the danger zone. Heart rate monitoring can also make sense for serious runners, cyclists, and other athletes who are eager to optimize their aerobic fitness.

But otherwise, there's no pressing need to know your heart rate.

"The majority of people simply don't need to monitor their heart rate," Gerald Fletcher, MD, professor of medicine at the Mayo Clinic in Jacksonville, Fla., tells WebMD.

Edward F. Coyle, PhD, agrees. He's a professor of kinesiology and health education at the University of Texas at Austin and director of the university's Human Performance Laboratory.

Coyle's work has included studying the muscular efficiency and physiological factors -- including heart rate -- in Lance Armstrong during his acclaimed cycling career. But Coyle says that for most people, it's not essential to track heart rate during exercise.

"If you're exercising for health, the most important thing to do is get off the couch," Coyle says. He says that for most people, the key is to "enjoy their exercise, so they keep doing it."

2. TRUE OR FALSE: Resting heart rate is a good indicator of aerobic fitness.

TRUE. Regular aerobic exercise makes your heart stronger and more efficient, meaning that your heart pumps more blood each time it contracts, needing fewer beats per minute to do its job.

"For most people, a normal resting heart rate is between 60 and 90 beats a minute," Coyle says. "Athletic training can lower that rate by 10 to 20 beats per minute."

But if you have a lower resting heart rate than someone else, don't assume that you're in better shape than them, or vice versa. Two people can be equally fit and have significantly different resting heart rates.

"Both a couch potato and a highly trained marathoner could have a heart rate of 50 to 60," says Benjamin D. Levine, MD, professor of medicine and cardiology at the University of Texas Southwestern Medical School and director of the Institute for Exercise and Environmental Medicine, both in Dallas.