|
Aerobic
Exercise, The word aerobic literally
means "with oxygen" or "in the presence of oxygen." Aerobic exercise
is any activity that uses large muscle groups, can be maintained
continuously for a long period of time and is rhythmic in nature.
Aerobic activity trains the heart, lungs and cardiovascular system
to process and deliver oxygen more quickly and efficiently to every
part of the body. As the heart muscle becomes stronger and more
efficient, a larger amount of blood can be pumped with each stroke.
Fewer strokes are then required to rapidly transport oxygen to all
parts of the body. An aerobically fit individual can work longer,
more vigorously and achieve a quicker recovery at the end of the
aerobic session.
WARM UPS
Before doing any exercise program
you should go through a warm up cycle of stretching movements.
A warm-up helps your body prepare itself for the exercise and
reduces the chance of injury. A warm-up routine should be a combination
of rhythmic exercise to raise the heartrate and muscle temperature,
it should also include static stretching through a full range
of motion. A good way to do this is by going through slow movements
of the actual aerobic exercise that will follow. If jogging is
the program then you could start out with a fast walk to elevate
the heart rate. Do not over do it in the warm up cycle and be
sure to reach all of the muscle groups. Most important is stretching
the lower back before doing any lateral movement of the upper
torso such as side bends.
STARTING A PROGRAM
When starting any program you should
do so in stages. The first week you should set up goals that are
not too strenous. For example if your goal is eventualy to be able
to jog 3 miles in an hour you start it in steps that your body can
handle. Try and see how much you can handle the first day without
overdue exertion then base yourself some weekly goals from there.
for example you might only be able to complete 1/2 mile this time.
Do that for a week then move it up to 1 mile, continue this until
you reach your set goals.
Setting Up A Schedule
Most experts say that 3-5 times
per week for a duration of 20-60 minutes within safe limits for
your age and heart condition is good.
Frequency, duration and intensity.
Frequency refers to how often you perform aerobic activity, duration
refers to the time spent at each session, and intensity refers to
the percentage of your maximum heartrate or heartate reserve at
which you work.
Most people find the best results
from an early evening schedule when the metabolism is at its peak.
Any time is good as long as you enjoy it and be consistent. Your
schedule should be easily integrated into your existing work and
eating habits. For you to be successful you must enjoy the program.
EATING BEFORE EXERCISE
Consider that you will probably
burn between 300 and 450 kCal in an aerobics class. Keep the caloric
content of the meal below that if you're intending to lose weight.
That pretty much lets out any sort of "heavy" meal. The average
American's diet is very high in protein, and relatively low in complex
carbohydrates, so complex carbs before an aerobic workout are probably
better. Keep the total calories from fat to 25% or lower, in general.
HEART RATE
The general formula for the average person is
220-age times 60% and times 90% of HRmax. For example, a 30-year
old would calculate his target zone using the above formula: 220-30=190.
190x.60=114 and 190x.90=171. This individual would try to keep his
heartrate between 114 (low end) and 171 (high end) beats per minute.
The Karvonen Formula calculates your heartrate
reserve range. To calculate it, take your pulse for one minute on
three successive mornings upon waking up. (We will be using the
case of a 30-year old male whose resting pulse was 69,70 and 71
for an average of 70 over the 3 days.)
Calculate target heartrate by subtracting your
age from 220 (220-30=190).
Subtract your average resting heart rate from
target heartrate (190-70=120).
The lower boundary of the percentage range is
50% of this plus your resting heart rate [(120 x .5) + 70 = 130].
The higher boundary is 85% plus your RHR [(120 x .85) + 70 =178].
Using the Karvonen Formula for percentage of heartrate reserve,
this 30-year old man should be working between 130 and 178 BPM.
Like the maximum heartrate formula, the Karvonen
formula can vary from individual to individual. Not every individual
is "average", and there can be large differences among people. Therefore
heartrate alone may not be the best indicator of how hard or how
well you are working.
It is important to note that the deviation in
both the age-specific formula and the Karvonen formula is due to
the estimation of HRmax. If you have an actual HRmax from a graded
exercise test, it will be more accurate. ACSM lists two formulas
for estimating HRmax, each one with a standard deviation of +/-
10-12 BPM:
HRmax = 220 - age (low estimate) HRmax = 210
- (0.5 * age) (high estimate)
HR = exercise intensity * HRmax * 1.15
Source: ACSM's Guidelines for Exercise Testing
and Prescription, 5th Edition, p. 274, Williams and Wilkins
WORKOUT INTENSITY
The Borg scale of perceived exertion is another
way of determining how hard you are working. Using your own subjective
Rate of Perceived Exertion (RPE) on a scale of 6-20 or a scale of
O-10, you determine how hard you *feel* you are working. A rating
of 12-16 ("somewhat hard" to "hard" on the 12-20 scale) or a rating
of 4-6 ("somewhat strong" to "very strong") on the 0-10 scale reflects
a heartrate of 60-90% of maximum and should be the target area for
which to strive.
Source: ACSM's Guidelines for Exercise Testing
and Prescription, 5th Edition, p. 68, Williams and Wilkins
There are several ways to increase intensity.
Increase your step height, use longer lever arms or add propulsion
moves (where both feet are off the step at the same time). If you
are going to add propulsion, or power as it is known today, make
sure not to do these moves for more than one minute at a time as
these moves result in higher vertical impact. All power moves should
be done as you go up onto the platform. Always step down without
power. Power moves are considered advanced, and should not be attempted
by beginners.
|
