17
Aerobic Fitness
The largest amount of oxygen that you can use
per minute during exercise is called your
maximum oxygen uptake
(MVOz). This is
often referred to as your
aerobic capacity.
The effort that you can exert over a prolonged
period of time is limited by your ability to deliver
oxygen to the working muscles. Regular
vigorous exercise produces a training effect that
can increase your aerobic capacity by as much
as 20 to 30%. An increased MV02 indicates an
increased ability of the heart to pump blood, of
the lungs to ventilate oxygen and of the muscles
to take up oxygen.
Anaerobic Training
This means "without oxygen" and is the output
of energy when the oxygen supply is insufficient
to meet the body's long-term energy demands.
(For example, 100-meter sprint).
The Training Threshold
This is the minimum level of exercise, which is
required to produce significant improvements in
any physical fitness parameter.
Progression
As you become fitter, a higher intensity of
exercise is required to create an overload and
therefore provides continued improvement.
Overload
This is where you exercise at a level above that
which can be carried out comfortably. The
intensity, duration and frequency of exercise
should be above the training threshold and
should be gradually increased as the body
adapts to the increasing demands. As your
fitness level improves, so the training threshold
should be raised. Working through your
program and gradually increasing the overload
factor is important.
Specificity
Different forms of exercise produce different
results. The type of exercise that is carried
out is specific both to the muscle groups
being used and to the energy source
involved. There is little transfer of the effects
of exercise, e.g. from strength training to
cardiovascular fitness. That is why it is
important to have an exercise program
tailored to your specific needs.
Reversibility
If you stop exercising or do not do your
program often enough, you will lose the
benefits you have gained. Regular workouts
are the key to success.
Warm Up
Every exercise program should start with a
warm up
where the body is prepared for the
effort to come. It should be gentle and
preferably use the muscles to be involved
later.
Stretching should be included in both your
warm up
and
cool down
, and should be
performed after 3-5 minutes of low intensity
aerobic activity or callisthenic type exercise.
Warm Down or Cool Down
This involves a gradual decrease in the
intensity of the exercise session. Following
exercise, a large supply of blood remains in
the working muscles. If it is not returned
promptly to the central circulation, pooling of
blood may occur in the muscles.
Heart Rate
As you exercise, so the rate at which your heart beat also
increases. This is often used as a measure of the required
intensity of exercise. You need to exercise hard enough to
condition your circulatory system, and increase your heart rate,
but not enough to strain your heart.
Your initial level of fitness is important in developing an exercise
program for you. If you are starting off, you can get a good
training effect with a heart rate of 110-120 beats per minute
(BPM). If you are fitter, you will need a higher threshold of
stimulation.
To begin with, you should exercise at a level that elevates your
heart rate to about 65 to 70% of your maximum heart rate. If you
find this is too easy, you may want to increase it, but it is better to
lean on the conservative side.
As a rule of thumb, the maximum heart rate is 220 BPM minus
your age. As you increase in age, so your heart, like other
muscles, loses some of its efficiency. Some of its natural loss is
won back as fitness improves.
The following table is a guide for those who are "starting fitness".
Age
25
30
35
40
45
50
55
60
65
Target Heart Rate
10
Second
Count
23
22
22
21
20
19
19
18
18
Beats
per
Minute
138
132
132
126
120
114
114
108
108
