The Truth About Heart Rate and Exercise
Do you really need to track your heart rate when you work out? Experts weigh in.
2. TRUE OR FALSE: Resting heart rate is a good indicator of aerobic fitness. continued...
"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
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.
3. TRUE OR FALSE: Maximum heart rate declines with age.
TRUE. As we all know, exertion makes the heart beat faster, and the
greater the exertion, the faster the heart rate. But there's an upper limit on
how fast your heart can beat, and that limit is affected by age.
"Maximum heart rate is unrelated to exercise training," Hirofumi Tanaka,
PhD, tells WebMD. He's an associate professor of kinesiology and health
education at the University of Texas and director of the university's
Cardiovascular Aging Research Laboratory.
"Whether you're a couch potato or a highly trained athlete, that rate
declines about seven beats per minute for each decade," Tanaka says. Regular
exercise can lower your resting heart rate, but it does nothing to slow the
age-related decline in maximum heart rate.
4. TRUE OR FALSE: Moderate exercise promotes weight loss more effectively than vigorous exercise.
FALSE. Weight loss is a matter of simple arithmetic: To shed
pounds, you must burn more calories than you consume. And when it comes to
burning calories, the greater the exertion, the greater the rate at which
calories are burned.
Working out at about 60% to 75% of your maximum heart rate (the so-called
"fat-burning zone") burns fewer calories than working out at 75% to 85% of your
maximum heart rate (the so-called "aerobic" or "cardio" zone).
But caloric burn depends on a workout's duration as well as its intensity --
and it's easier to work out longer when exercising at a lower intensity.