I KNOW IF I'M IN THE TRAINING ZONE?
range of exercise intensities and under some circumstances you
may benefit more if you exercise at the low end of the range.
But how do you know if you're in the range?
been a major change since I wrote my original book "Fit or Fat?"
in 1977. At that time the intensity of exercise was largely based
on the formula 220 minus your age = maximum heart rate.
In those days
we thought that this formula applied to a large percentage of
the population, as much as 86 percent. We now know it applies
to only about 60 percent. Approximately 15 percent of the population
have hearts that beat considerably slower than the predicted maximum
and another 15 percent have hearts that beat much faster. This
doesn't mean there's anything wrong with these hearts or that
they are abnormal. It just means they aren't "average".
your heart beats faster than average during exercise. If you're
thirty years old, you would expect your heart to beat 220 minus
30, or 190 beats a minute if you exercise at maximum. But yours
goes 210. It's as if you have a Kawasaki heart: it's built very
well but it's made to function at a high RPM. When you exercise,
your heart goes much faster than all the charts say it should,
and your aerobics instructor is afraid you're going to die any
minute. You're not - you just have heart that beats very fast
and is therefore off the chart.
percent of the population (I'm only guessing at this number) is
taking medication that affects heart rate. These people's hearts
may fit the predicted formula, but the medication artificially
depresses their heart rate during exercise. Pulse monitoring as
a measure of exercise intensity is not reliable for this group
If you add
together the 15 percent of people with slow-beating hearts, the
15 percent with fast-beating hearts, and the approximately 10
percent on some kind of medication, you have 40 percent of the
population for which the 220 minus age formula becomes completely
useless. Only about 60 percent of the population finds the formula
to be a useful one.
Let me tell
you a newer method. The new approach is simply to use common sense.
When you are doing aerobic exercise, keep in mind the basic intention
of the exercise. You're not trying to burn a lot of calories.
You're saying to your body, "Please adapt to this so that tomorrow
I can exercise better than I did today."
What you are
really after is an adaptation phenomenon, since the body seems
to adapt to whatever treatment it receives. It adapts to hard,
intense exercise by changing muscles so that they burn sugar well
and fat poorly. Slow, gentle exercise, on the other hand, turns
muscles into fat-burning machines. It's the time you spend urging
your body to change that really matters. The body adapts beautifully
to steady pressure, just as teeth can be moved by the gentle,
steady pressure of braces. I see men who run like crazy around
the local track, proud that they can cover a mile in six minutes
flat, and then wonder why they still must fight a bulging waistline.
Such exertions are as effective in weight control as trying to
move teeth with a hammer. Run slower and longer and let your body
in mind, you need to adjust the intensity of your exercise; your
pace should be comfortable enough that you can continue beyond
the minimum twelve minutes without feeling fatigued. You should
be breathing deeply but not gasping. Some people call this the
"perceived level of exertion," while others simply use what they
call the "talk test." Say you are jogging with a friend. Is he
able to talk, but you are not? Each of you should be able to talk
a little bit, but neither of you should be able to sing an aria.
For fun, try singing "God Bless America". If you can't get beyond
the first word without gasping, you're exercising too hard. On
the other hand, if you get past "land that I love" before you
need your first breath, you should speed up.
When I'm teaching
people how to exercise, I use the "talk to me" test. It's the
same basic idea. If you're on a stationary bicycle, I say, "Can
you talk to me? What's your name? Where do you live? What's your
phone number?" If you can't talk to me without huffing and puffing
and groaning, I know that the bicycle tension is too tight or
you're pedaling too fast. Either one means you are doing anaerobic
exercise. Your muscles are working without oxygen.
according to your perceived level of exertion or by using the
talk test just boils down to using common sense. As you exercise,
think to yourself, "Am I doing something so gentle and easy that
I can go on for twenty, twenty-five, thirty minutes? Will my body
change tonight as a result of this, or am I exercising too slowly
or too fast?" If you are able to talk haltingly and are breathing
deeply but comfortably, then you are almost certainly within the
training zone. There's nothing wrong with occasionally exercising
outside your training zone, but it doesn't fit the definition
Once you have
found a comfortable exercise intensity, try taking your pulse.
For 60 percent of you, the pulse you get should be between 65
and 80 percent of the formula 220 minus your age (maximum heart
rate). But maybe you belong in the other 40 percent. Stick with
the comfortable, common-sense intensity. We would probably find
that the heart rate you get while exercising at that comfortable
rate is 65 to 80 percent of your true underlying maximum heart
rate as determined on a treadmill. Even though it doesn't fit
everyone, we still recommend heart-rate monitoring of exercise
as a useful tool.
more on heart rate training see Smart