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How Hard Should I Exercise?
Studies show that to achieve the benefits of aerobic exercise, it is necessary to
work out hard enough to raise your heart rate to a certain minimum level, called
the “training zone.” Your training zone depends on your age and level of
fitness.
Diagram 14 shows your recommended heart rate training zone, which is
calculated using your age and your maximum attainable heart rate. The chart is
based on a resting heart rate of about 72 for males and 80 for females. Your
optimum training zone is between 65% and 80% of your maximum heart rate.
For efficient aerobic exercise, work only hard enough to keep your heart rate in
this zone. You will obtain the greatest fat-burning benefits when you exercise
within the optimum training zone.
Pushing yourself beyond the recommended range, (that is, exercising so hard
that your heart rate rises above 80% of maximum) can overstress your
muscles. To increase cardiovascular improvement, exercise
longer, not harder.
Keep in mind that this zone is an approximation, to be used as a guideline—
individual heart rates vary according to several physiological factors. To
determine your training zone, find your age on the diagram, and then find the
line where they intersect. For example, if you are 35 years old, your training
zone is between 114 and 140 beats per minute. Remember this zone—this is
the heart rate zone you should try to maintain as you work out.
If you do not have an accurate heart rate monitor, you can determine your heart
rate by taking your pulse at a place that you can reach easily and comfortably
while you exercise. Typical places for measuring heart rate are directly over the
heart on the left side of the chest, on either side of the neck, over the temple, or
on the thumb side of either wrist. Wherever you measure your pulse, make
sure that you use your index and middle fingers—not your thumb. Your thumb
has a strong pulse which can affect your pulse rate reading.
Diagram 14
Training zones
HEART RATE TRAINING ZONE
70
80
90
100
110
120
130
140
150
160
170
180
190
20
25
30
35
40
45
50
55
60
65
70
75
YOUR AGE
YOUR HEAR
T RA
TE
MAX.
HEART
RATE
80% OF
MAX.
HEART
RATE
65% OF
MAX.
HEART
RATE
124
120
114
110
107
104
101
98
91
152
148
140
136
132
128
124
120
116
112
180
175
170
165
160
155
150
145
140
135
RECOMMENDED TRAINING ZONE
88
117
144
108
94
185
190
