The most time-honored method for determining maximum heart rate is for
men to subtract their age from 220 and for women to subtract their age from
- Keep in mind that this formula gives you only an estimate. Your true max
may be as many as 15 beats higher or lower. Also, this formula is generally
used for activities during which your feet hit the ground. (To estimate your
max for bicycling, subtract about five beats from the final result; for swim-
ming, subtract about ten beats.)
Using that easy formula to find your max, find your target heart-rate zone by
calculating 50 percent and 85 percent of your maximum. Here’s the math for a
40-year-old man:
220 – 40 = 180This is his estimated maximum heart rate.
180 ×0.50 = 90This is the low end of his target zone. If his heart beats less than 90 times per
minute, he knows that he’s not pushing hard enough.
180 ×0.85 = 153This is the high end of his target zone. If his heart beats faster than 153 beats
per minute, he needs to slow down.
Okay, so now you know how to figure out your target heart-rate zone. But
how do you know if you’re in the zone? In other words, how do you know
how fast your heart is beating at any given moment? As we mention earlier in
this chapter, you can check your heart rate in two ways: taking your pulse
manually or using a heart-rate monitor.
Taking your pulse manually
Watch any quality aerobics video or take any decent cardio class at the gym,
and you hear the instructor yell out, “Okay, everybody, time for a heart-rate
check.” On this cue, the participants place their fingers on their necks or on
their wrists. Taking your pulse manually can be wildly inaccurate, so concen-
trate when you do it.
To use the neck method, place your index and middle fingers (not your thumb)
in the groove on either side of your throat pipe. When you feel a beat, you’ve
found your carotid artery. The neck method isn’t our favorite because your
heart rate is harder to find on your neck and because some experts feel that
the act of pressing against this artery may actually shut off blood and oxygen
supply to the brain, causing you to faint. If you use this method, be careful not
to push too hard. We prefer the wrist method, which we explain in Chapter 2.
Chapter 8: Cardio Crash Course 113