N.A.S.A. Study |
Resistance Rebounding |
N.A.S.A. CONFIRMS IT!
“…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 Wennergren 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 had 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 exercising.
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 scientist recorded their statistics and compared them with previous treadmill studies for accuracy.
A week later, these same athletes returned to bounce on a trampoline at four different heights with a 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 vibrations 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 but quite frankly, were expected by us at the “Institute.” Following are some of the results revealed by this team of scientists from NASA:
1. The 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.
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 individual.
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 the 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 on the heart.
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 on rebound units have been measured only as high as 3.5-G’s, so that any activity on a rebound unit 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 the 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 injury, or anyone else who needs exercise but is hampered by a pre-existing physical condition.
Dr. Harry Sneider – Resistance Rebounding Analysis
Harry and Sarah Sneider's Olympic Trainer, an exercise package consisting of three sets of hand-held weights, 1, 2, and 3 pound sandbags to be used in conjunction with rebounding.
One goes through an organized series of upper body movements while walking, jumping or running on a rebounder. Here are his easy-to-understand steps to an amazing end result.
Step 1 - If one stands still on the rebounder and holds a one pound weight in each hand; it will exert one pound pressure on each arm, a total of two pounds on the trunk and legs.
Step 2 - If one jumps on a rebounder creating a 2 G force, the weight will create 2 pounds of force at the bottom of the bounce on each arm; a total of \ pounds on the trunk and legs.
Step 3 - If one creates the bounce by rhythmically moving the weights in the hands forcefully up and down, the G force is at least doubled again at the bottom of the bounce and 1 G of deceleration at the top of the bounce
This subjects each arm to an additional five pounds of resistance, or a total of 10 pounds.
Step 4 - If one moves the weights from the shoulders to the waist while sinking into the mat six inches and bouncing off the mat six inches, the weights in the hands move upward a total of approximately 2 feet each bounce.
Step 5 - Assume one bounces six inches off the mat 100 times in a minute, moving the weights 1 foot in a curl exercise. That would be moving 10 pounds x 2 feet x 100 times, or 2000 foot/pounds of work in one minute...or, if you used 2 pound weights with the same exercise, it would be 4000 foot/pounds of work... or, if you used the three pound weights, 6000 foot/pounds.
Step 6 - For the purpose of illustration, let's assume that you use the two pound weights moving them an average of one foot while sinking six inches into the mat and bouncing six inches off the mat. You complete the Daily Dozen (a series of exercises shown in "Harry and Sarah Sneider's Olympic Trainer"), 25 repetitions, 3 sets. It takes you 20 minutes. This would be the equivalent
of moving a 40 ton freight car 1 foot in 20 minutes, or a Volkswagen up 40 steps in 20 minutes, or curling a 100 pound barbell 200 times in 20 minutes!
This only factors the weights in your hand. Next, your body weight is factored.
Step 7 - Assume you weigh 150 pounds and are bouncing high enough to create 2 Gs. At the bottom of the bounce you weigh 300 pounds. Your entire weight is moved upward 1 foot 100 times a minute x 20 minutes, or 600,000 foot/pounds!
“That's the equivalent of moving a 300 ton freight train engine1 foot in 20 minutes! Add that to the 40 ton freight car and you will begin to understand why resistive rebounding is destined to revolutionize our concept of weight training. Granted, the springs in the rebounder
do some of the work, but that's the beauty of it. Your cells can't tell the difference!”
Eric resistance rebounding
with 2 lb weights in each hand.
Dr. Morton Walker
Dr. Walker has established himself as a major author in the self-help and holistic health fields. He is an award-winning professional medical writer, having over fifty books to his credit,
as well as over 1000 magazine articles. He is a highly sought after lecturer and appears on TV and radio shows. Toil and sweat your way to fitness no more! Rebounding aerobics is here! A non-strenuous exercise system with more benefits than ordinary sports
like tennis or jogging, rebounding makes exhausting workouts a thing of the past.
In his book, Jumping for Health - A Guide to Rebounding Aerobics, Dr. Morton Walker details how this enjoyable activity has helped folks from eight to eighty enhance
their health and fitness. What it did for them, it can do for you.
To read Dr. Walker's article, published in "Townsend Letter for Doctors", click here. The article features the NEEDAK® Rebounder.