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studies on rebound exercise
For similar levels of heart rate and oxygen consumption, the magnitude
of the biomechanical stimuli is greater with jumping on a trampoline
than with running, a finding that might help identify acceleration
parameters needed for the design of remedial procedures to avert
deconditioning in persons exposed to weightlessness.
The above statement is one of several made in a
scientific study published in the Journal of Applied Physiology 49(5):
881-887, 1980, which confirms many of the statements previously made in
the Miracles of Rebound Exercise. The research was performed by the
Biomechanical Research Division, NASA-Ames Research Center, Moffett
Field, California, in cooperation with the Wenner-Gren Research
Laboratory, University of Kentucky, Lexington, Kentucky.
The four scientists, A. Bhattacharya, E.P.
McCutcheon, E. Shvartz, and J.E. Greenleaf, secured the assistance of
eight young men between the ages of 19 and 26 to each walk, jog, and
run on a treadmill which was operated at four different speeds and then
jump on a standard sized trampoline at four different heights to
compare the difference between the two modes of exercise. Although
treadmill running has been studied many times before, the scientists
found that measurements of the necessary variables have not been
reported previously for trampoline exercise.The trampoline testing was
conducted at least one week after the treadmill testing.
The six measurements which were taken on all
eight of the subjects were:
1. A pulse before exercising.
2. A pulse immediately after exercising.
3. The amount of oxygen consumed while exercising.
4. The amount of G-force experienced at the ankle while exercising.
5. The amount of G-force experienced at the lower-back while
6. The amount of G-force experienced at the forehead while exercising.
The pulse was obtained by a battery-powered electrocardiographic unit
taped to the subject's body which transmitted its signals to a
custom-designed receiver which in turn recorded the information by
electronically writing it on a chart.
The oxygen consumption was measured with a K-meter
which the subject carried on his back.
The G-force experienced by the ankle, back and
forehead of each of the university students was measured by small
sensitive accelerometers which were placed in plexiglass holders that
were taped to the ankle, the small of the back, and the forehead.
After a thorough medical examination, the healthy
students were issued a pair of shorts and new Nike running shoes to
standardize the conditions to be measured. They were given
familiarization sessions on laboratory procedures, treadmill running
and trampoline jumping to ensure the exercise techniques would be the
same. Each student then walked or ran four different speeds on the
treadmill with a five to ten minute rest period between runs while the
scientists recorded their statistics and compared them with previous
treadmill studies for accuracy.
A week later, these sane athletes returned to
bounce on a trampoline at four different heights with 5 to 10 minute
rest period in between exercise sessions. Again the scientists recorded
their statistics, only this time, they had no previous studies to
compare them to. Since trampolining had not been previously studied,
the only studies available were the preliminary studies which began in
August of 1977 on passive restrained humans and animals exposed to
increasing frequency and amplitude of vibration forces designed to
increase heart rate and metabolic activity.These responses measured by
whole-body vibration resemble those during mild exercise and suggest
that perhaps body vibration could be used in place of exercise.
The results of this study were startling to
the scientists. Following are some of the results revealed by this team
of scientists from NASA:
G-force measured at the ankle was always more than twice the G-force
measured at the back and forehead while running on a treadmill.
This helps to explain shinsplints and knee
problems, especially when the natural shock absorbing system of the
body becomes so fatigued that it doesn?t do its job correctly, thus
throwing added unexpected forces on already tired muscles, ligaments
and tendons, forcing them beyond the point of rupture.
2. While jumping on a trampoline, the
G-force was almost the same at all three points, (ankle, back,
forehead) and well below the rupture threshold of a normal healthy
This makes it possible to exercise the entire body
knowing that there is no undue pressure applied to part of the body
such as the feet, ankles, and legs, and at the same time knowing that
each part of the body is receiving the necessary environmental stresses
it needs to become stronger cell by cell.
3. The external work output at
equivalent levels of oxygen uptake were significantly greater while
trampolining than running. The greatest difference was about 68%.
The efficient use of the vertical forces of
acceleration and deceleration to produce internal loading by directly
opposing the gravitational pull develops more biomechanical work with
less energy expended, thus less oxygen used and less demand placed on
4. While trampolining, as long as the
G-force remained below 4-G's, the ratio of oxygen consumption compared
to biomechanical conditioning was sometimes more than twice as
efficient as treadmill running.
It is important to note that although this
experiment was performed on a trampoline where the participants were
able to develop a G-force as high as 8-G's, the efficient use of energy
was below 4-G's. People involved in rebound exercise with Kangoo Jumps
have been measured only as high as 3.7 G's, so that any activity on
Kangoo Jumps is more efficient than treadmill running at any speed.
5. With the G-force the same as or
greater than 4-G's,there was no significant difference in the oxygen
uptake between the two regimens.
Even when a person is able to develop a force on a
trampoline of more than 4-G's, although it is no more efficient as far
as oxygen consumption than running, it is still much better on the
lower extremities because the cells are still below their rupture
threshold providing a safe way to exercise.
6. Averting the deconditioning that
occurs during the immobilization of bed rest or space flight, due to a
lack of gravireceptor stimulation (in addition to other factors ),
requires an acceleration profile that can be delivered at a relatively
low metabolic cost for equivalent metabolic cost, and acceleration
profile from jumping will provide greater stimuli to gravireceptors.
This statement verifies the fact that rebound
exercise is an excellent exercise for our senior citizens, those
physically handicapped, those who are recuperating from an accident or
an injury, or anyone else who needs exercise but is hampered by a
pre-existing physical condition.