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Demonstrating and Predicting Aerobic PowerTeacher: Charles E. Geach; Irvin High School;
El Paso, TX
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Most students are familiar with or have some understanding
of the concepts of aerobic and anaerobic respiration at the cellular
level. During exercise, muscle contraction requires energy (ATP),
which is supplied by both the aerobic and anaerobic metabolism
of nutrients. Short bursts of high intensity exercise mainly utilize
anaerobic energy sources, while exercise enduring longer than
3-5 minutes will utilize energy provided by aerobic metabolism.
Students often have a difficult time being able to see an application
of these concepts in human physiology. This lab activity will
demonstrate anaerobic power in a physiologic way to which students
may be able to relate.
Aerobic power may be illustrated physiologically by the running
of longer than 3-5 minutes. In order to run a marathon, much oxygen
will be required to complete the race. Long distance runners train
their bodies to utilize oxygen in the most efficient way to be
able to win the race.
Anaerobic power may be illustrated by running a short distance
(sprint) race. In order to run a 100 m. dash, very little oxygen
is required. Your body is running almost totally on anaerobic
power because the race is over by the time your body has a chance
to replenish oxygen to the cells
The Wingate Anaerobic Test is a measure of this anaerobic power. The Wingate test uses an exercise bike that can be weighted for resistance and also has a counter for revolutions of the fly wheel per sec. A person pedals all out for 30 sec. against a resistance set by percent of body weight. The test can measure:
This lab activity uses a modification of the Wingate test as
a means of demonstrating and predicting anaerobic power. This
test is modified so that a simple exercise bicycle, one that might
be available to the average teacher, may be used. It also uses
percent fatigue as a predictor of anaerobic power. The exercise
bicycle needs to be able to measure mph or rpm's and also have
a means of arbitrarily setting resistance (weights or belt). The
resistance must be set at a challenging setting, that is, a setting
at which the student will have to pedal the full 30 sec. at a
maximum effort. Use of the same resistance setting for all students
will reduce the number of variables in the test. Generally, the
higher the resistance, the higher the peak power.
A stopwatch will be needed to time the 30 sec. test. A recorder
needs to view the speedometer during the test and record mph or
rpm during the test. At the end of the test a comparison of the
maximum (peak power) to the minimum mph or rpm is made. There
should be a significant drop off in speed. This difference is
the fatigue factor and can be a predictor of anaerobic power.
The students with the highest peak power and higher fatigue factors
should do better at anaerobic activities (Bar Or, 1987). This
lab may require some pilot testing in order to find a resistance
setting most suitable to a given individual and for a particular
exercise bicycle.
I did some preliminary testing with my own students at school.
The test turned out to be reproducible. I had a student do the
test one day and get a 44% fatigue factor and 2 days later get
another 44% factor. The test tended to be predictable. A cross
country track student had a 17% fatigue factor while a student
who is a sprinter on the track team achieved a 55% factor. The
test also seems to have a correlation to the actual Wingate test.
I tested myself at school and I had a 41% fatigue factor. During
my summer research testing using the exercise bicycle equipment
at the Human Performance Lab I had a 45% fatigue factor. Further
testing needs to be done fully to validate this protocol, but
I believe it is a way to demonstrate to your students the concept
of anaerobic power.
1. Have student warm up at a moderate resistance for 5 min. on the exercise bike.
2. The student should then rest for 5 min.
3. The student should then pedal as fast as possible. Once the maximum speed has been reached, apply the bike's resistance to start the test. The resistance should be such that the student will have difficulty pedaling at maximum effort for 30 seconds. As soon as the resistance is applied a timer should begin timing the 30 sec. test. Pedaling should be continued as fast as possible for the full 30 sec. Highest and lowest mph or rpm should be recorded during the 30 sec. portion of the test. The fatigue factor should be calculated by finding the difference between the highest and lowest mph or rpm and dividing by the highest number, that is, (Highest Speed - Lowest Speed) / Highest Speed.
4. The students should then make a chart comparing peak power and the fatigue factors for the entire class.
5. The same students, on another day, will be timed in a 100 m. dash and a correlation should be made to their bicycle test results.
1. Why is this test an example of anaerobic power?
2. Give examples of other activities that use anaerobic power.
3. Explain why bursts of intense exercise are not completely anaerobic.
4. Give examples of aerobic power activities.
5. Based on the chart you made, theorize which students in the class would do better in sprinting events.
6. What other factors beside anaerobic power might effect how fast a person can run sprinting events?
7. Why is sprinting considered an anaerobic activity?
8. Design an activity the track coach could use to predict
who his sprinters and long distance runners are before they even
run a race.
Have students test members of the track team comparing sprinters
to long distance runner using runners the modified Wingate test.
I would like to acknowledge the assistance of the personnel
at The Human Performance Laboratory, William Beaumont Army Medical
Center in the development of this activity: Idelle M. Weisman,
Col, MC; R. Jorge Zeballos, M.D., D. M. Sc.; Matthew Taylor, Exercise
Physiologist; Jan Peterson, Editorial Assistant
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American
Physiological Society |
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