5. TRUE OR FALSE: There's a simple and reliable formula for calculating your maximum heart rate.
TRUE. There is such a formula -- but there are two big caveats.
For starters, it's not the familiar 220 minus your age in years. That formula, first promulgated in the 1960s, works reasonably well for people under age 40. But it overstates the maximum heart rate for older people.
A more accurate formula is the one published in 2001 by Tanaka in the Journal of the American College of Cardiology: Multiply your age by 0.7 and subtract that figure from 208. For example, a 40-year-old has a maximum heart rate of 180 (208 - 0.7 x 40).
Formulas aside, maximum heart rates vary, even among people of the same age. "The formula is only relevant for groups of people," Levine says. "For individuals, the prediction is off by plus or minus 10 to 20 beats per minute."
It's possible, of course, to determine your maximum heart rate by running or riding a bike to the point of exhaustion. But because it can be risky, exercising that intensely is not recommended for men over 45 or women over 55, as well as for heart disease patients or people with heart disease risk factors, unless they have been exercising regularly or have been cleared to exercise by their doctors.
6. TRUE OR FALSE: Using a heart rate monitor can help boost your fitness level.
TRUE. Electronic heart monitors, typically consisting of a wristwatch-like display and an electrode-studded chest strap, are used by serious runners, cyclists, etc. while training and even during races. By providing accurate, real-time heart rate information, the monitors help athletes pace themselves.
But even if you're not preparing for a marathon or a century ride, using a heart rate monitor can help motivate you to exercise. How? By turning your regimen into a solitaire of sorts: Can your regimen lower your resting heart rate? Can you exercise at the same pace but get your heart to pump more slowly? Can you shorten the time it takes your heart rate to return to normal after a workout?
It's not easy to answer these questions when you take your pulse manually, but quite easy with a heart rate monitor. "No one really needs a heart rate monitor," Fletcher says. "But some people love to play with these things, and that motivates them to exercise."