Whatís all the fuss about?
Tae Bo, a form of high impact aerobics that combines the moves of Tae Kwon
Do, karate, boxing, ballet, and hip_hop dancing is the newest craze in gyms
and homes across the country. Tae Bo, which stands for Total Awareness
Excellent Body Obedience, was developed by Billy Blanks in the late 1980ís.
Blanks, a seven_time world karate champion and black belt in six martial
arts, developed Tae Bo in the basement of his home. Atfter encouragement
from family and friends, The Blankís World Training Center in Sherman Oaks,
CA was opened, introducing Tae Bo to local townspeople and limited Hollywood
celebrities. By word of mouth, Tae Bo gradually gained popularity, itsí fame
peaking with the release of the video package in August of 1998.
The four tape video package includes an instructional video, basic
workout, advanced workout, and an eight_minute workout. The videos are
commonly featured on a late night infomercial where the package can be
purchased for three payments of $19.95. The infomercial, featuring
testimonials from successful users, and a motivational speech from Blanks
himself, has sold over one million copies since 1998. "If youíve got the
will__Tae Boís the way" promises the announcer, for thousands of users this
seems to be the truth.
Troy Obrero , a well educated personal trainer in San Francisco, CA gives
Tae Bo his approval: "Tae Bo is an excellent cardiovascular workout with very
good distractions." Obrero targets lack of variety as the reason for failure
of many workout regimens, he claims that Tae Bo provides the necessary
novelty and challenge to keep users hooked. Very few people have done the
type of movements done in Tae Bo on a regular basis, continues Obrero, this
leads to its extreme effectiveness in toning and defining the entire body.
Blanks encourages his clients to work on their bodies from the inside
out; he claims: "results are imminent from the very first Tae Bo workout, as
completing it makes you feel great about yourself." Overall Blanks says his
Tae Bo workouts can improve balance, coordination, flexibility, and will tone
and define muscles. The workout regimen is exhaustively aerobic and
therefore yields phenomenal cardiovascular benefits. Finally, perhaps the
most appealing aspect of a Tae Bo workout is itsí proven calorie burning
effectiveness. An hour long Tae Bo workout will burn 500 to 800 calories,
compared with the 300 to 400 calories burned with a more conventional
The world wide web is full of glowing recommendations from faithful Tae
Bo users. Although the workout seems to be most popular with women in their
twenties and early thirties, Blanks claims that Tae Bo is a great workout for
males and females of all ages. The following are examples of Tae Bo success
Linda Maricle from Pekins, South Carolina is a 38 year old mother of 16
year old twins. She has been doing Tae Bo with her boys for several months.
Maricle attributes her improved coordination and toned body to the Tae Bo
video library. "Tae Bo is so hard that you get quite a feeling of
accomplishment just by finishing."
Carol Ricci, 45, of Egg Harbor City, NJ, has dropped one dress size
since beginning Tae Bo. "I have noticed greater muscle definition; biceps,
shoulders, abdominal, and glutes since incorporating Tae Bo into my
workouts. It is really challenging, and I can see progress from workout to
Kristen Dollard, 26, has had great success with Tae Bo. "I was
desperate because I had tried everything and nothing worked__until Tae Bo. I
lost 45 pounds and 33 inches (overall) and have maintained it for a year!"
Lauren Sacks, 31, has also caught the Tae Bo bug. "Bring Billy Blanks
into your living room and youíll find a whole new thing that you never knew
existed. Once you try this youíll never go back to anything else and youíll
Precautions__Is Tae Bo for everyone?
According to the American Council on Exercise (ACE) which serves as a
consumer watchdog on exercise products and programs, to prevent injury,
beginners should take precautions when beginning Tae Bo and other kick_boxing
workouts. ACE advises that potential Tae Bo users should achieve a solid
fitness foundation before beginning their workouts as even basic classes or
videos require above average endurance, flexibility, and strength. Once a
reasonable level of fitness has been achieved, beginners should be sure to
master proper technique before starting a full fledge workout. Common
beginnerís mistakes include overextending and locking joints when punching or
kicking which can result in painful muscle damage.
Kathy Smith, a well known aerobics instructor and fitness expert,
recently began taking kick_boxing classes. Although Smith has boxed for
years and is in excellent shape, she found the workout incredibly strenuous.
"For the first two weeks, every muscle ached and my back felt miserable. I
began to wonder whether kick_boxing is more of a workout than many people
might be able to handle." Kick_boxing places stresses and strains on the
body that are much more severe than those endured during a more traditional
aerobic workout. Tae Bo newcomers often start out too hard and too fast,
putting too much stress on their joints and surrounding tissue which can lead
to injuries. Smith cautions that those who have been sedentary, especially
if theyíre over 30 or overweight, should proceed slowly for at least eight
Finally, although the martial art undertones are what help make Tae Bo
such an effective cardiovascular workout, Troy Obrero believes this leads
many people to falsely assume that they are learning a martial art. "Nothing
could be further from the truth" cautions Obrero; Tae Bo is not a
self-defense course and practitioners should not attempt to use the
techniques outside of their workouts.
The Scientific Evidence
Although it is widely accepted that physical activity is imperative for
achieving good health and fitness, the type of exercise recommended has been
a topic of intense debate. High impact exercise is characterized by the
stress it places on the body and usually involves bouncing and jolting; low
impact exercise is much easier on the body but tends to be a less efficient
calorie burner. Low impact exercise has often been suggested as a safer,
user friendly way for people of all shapes and sizes to get and stay in
shape. Despite the risk factors, high impact exercise is widely practiced,
as evidenced by the popularity of the Tae Bo program. Do the stresses Tae Bo
places on the body outweigh itís extreme calorie burning effectiveness? Is
Tae Bo safe for everyone, or just for the small minority of the population
who can be considered "in shape"? For the answers to these and other related
questions, we turn to the scientific literature.
Although no studies have been performed on Tae Bo specifically, evidence
can be extrapolated from studies on strenuous and high impact exercise. One
such study sought to determine the long term pattern of relaxation times and
muscle volume changes in human skeletal muscle after intense exercise (Foley
et al., 1999). Six young adult men performed two bouts of eccentric bicep
curls separated by eight weeks. Blood samples, soreness ratings, and
magnetic resonance imaging of the muscles were taken immediately before and
after each bout of exercise and at varying intervals throughout the eight
weeks. Results of the MRI showed a gradual increase in total volume of the
imaged arm after bout one, but volume returned to pre_exercise values within
two weeks. The exercised flexor compartment swelled by over 40%, but after
two weeks reverted to a volume 10% smaller than pre_exercise values and
maintained this volume through eight weeks post_exercise. This suggests
complete or partial destruction of a small sub_population of muscle fibers,
resulting in a slight loss of strength and extension in the exercised arm.
After bout two, pain ratings and muscle swelling were significantly lower;
this supports the idea of a repeated_bout effect, in which a muscle adapts to
protect itself from further damage.
Applied to Tae Bo, which when done incorrectly can result in the
eccentric extension of a number of muscle groups, this study seems to support
the precautions expressed in other less scientific literature. If done
incorrectly Tae Bo can produce extensive long lasting muscle damage, by
proceeding slowly and focusing on technique however, these effects can be
minimized. The repeated_bout effect mentioned in this study would suggest
that by performing the same exercises at regular intervals, the body will
slowly adjust until the soreness and swelling initially produced begin to
Strenuous exercise is followed by a decreased concentration of
lymphocytes and impaired natural immunity; the findings on this topic were
compiled in a article by Pederson et al. in 1999. Regular lower impact
exercise may increase resistance to infections, while strenuous exercise is
associated with increased respiratory tract infections. Lymphocyte
concentration increases during exercise and falls below pre_exercise values
following intense long duration exercise, this accounts for the so called
"open window" of altered immunity. Findings on exercise in the elderly show
an overall decline in the immunity to infection, especially as related to
strenuous exercise. It has been found however, that the immune system of
older individuals can respond to the stress imposed by a single bout of
Various nutritional supplements have been tested for their effectiveness
in eliminating post_exercise altered immunity. The most effective of these
supplements was carbohydrates. Compared with placebo, the ingestion of
carbohydrates before, during, and after strenuous exercise was found to
diminish the negative immune response in some studies. An advanced Tae Bo
workout could be considered strenuous exercise, especially for beginners and
those who are not frequent exercisers. These findings suggest that Tae Bo
practitioners should take extra care to avoid increasing their susceptibility
to infections. Proper nutrition, as well as carbohydrate supplementation,
should be used to combat these possible negative effects.
A review of six case studies warns experimenters against the use of
eccentric exercise protocols to induce and study mild forms of muscle
damage. In two different studies involving a total of 231 subjects, maximal
eccentric actions of the elbow flexors were used. Each subject performed two
sets of 25 actions, separated by a five minute rest period. In these two
studies a total of 8 adverse events occurred in which subjects experienced
extreme swelling and prolonged loss in the ability of the muscle to generate
force. At itsí worst, the size of the affected arm was approximately twice
the size of the normal arm. Normal recovery time of force generation
following eccentric exercise is two weeks, in these cases however, subjects
showed losses of up to 47 days in the ability of the muscle to generate
force. These symptoms are consistent with a condition called
rhabdomyolysis. Rhabdomyolysis is defined as a degeneration of muscle cells
following strenuous, overexertion exercise, and is characterized by muscle
tenderness, weakness, swelling, dark urine, and increased levels of muscle
proteins in the blood. With dehydration or heat stress, myoglobin can
precipitate in the kidneys and cause renal failure.
Although none of the six cases reviewed appeared to meet all the
diagnosing criteria for rhabdomyolysis, it should be recognized that only one
muscle group was involved. Such exercise involving several muscle groups
could be dangerous. Although in general, high_force eccentric exercise poses
little threat to otherwise healthy individuals with no history of
musculoskeletal disease or injury, this study showed a 3% incidence of
extreme negative responses to such exercises. This study provides further
evidence that the highest precautions should be taken to avoid muscle damage
with high impact exercises such as Tae Bo.
When performed carefully and correctly high impact exercise does have
positive effects, especially in younger participants. A study of 71
premenarcheal girls, 9_10 years old, explored the lean mass, strength, and
bone mineral response to a ten month high impact strength_building exercise
program (Morris et al., 1997). The girls were divided into experimental and
control groups, at baseline these groups did not differ in height, total body
mass, pubertal development, calcium intake, or external physical activity.
After ten months, the exercise group gained significantly more lean mass,
less body fat content, greater shoulder, knee and grip strength, and
increased levels of bone mineral content as compared with the control group.
These results suggest that high impact, strength building exercise, such as
Tae Bo, is beneficial for increasing strength, lean mass gains, and bone
mineral acquisition in premenarcheal girls. This finding is especially
important, as the enhancement of bone mineral acquisition during growth is
thought to help prevent osteoporosis.
A study by Bassey, Rothwell, Littlewood, and Pye (1998), suggests that
the positive effects of high impact exercise on bone mineral density found in
young girls do not apply to older, post_menopausal women. Randomized
controlled trials were used in both pre_ and post_menopausal women to assess
the effects of a vertical jumping exercise regime on bone mineral density.
The exercise consisted of 50 vertical jumps with a mean height of 8.5 cm on
six days per week. After five months, pre_menopausal women showed a
significant increase in femoral bone mineral density, while at both 12 and 18
months post_menopausal women showed no difference in bone mineral density
when compared with controls. It appears that pre_menopausal women respond
positively to brief high impact exercise but post_menopausal women do not.
For this reason, as well as the other risks associated with high impact
exercise, older women may benefit more from regular low impact exercise than
from a high impact workout such as Tae Bo.
A final study of interest compared the exercise intensity and rating of
perceived exertion of a high impact and low impact university aerobic dance
session (Grant, Davidson, Aitchison, and Wilson, 1998). Ten women with a
mean age of 22.6 years were randomly assigned to high impact and low impact
sessions; heart rate, oxygen uptake, and rating of perceived exertion were
measured throughout each session. All three of these measures were
consistently higher during the high impact session than during the low impact
session. For the participants of this study, all young fit females, high
impact exercise has the potential to maintain or improve aerobic fitness,
while low impact activity has a limited training effect and may actually
result in detraining for some individuals. Consistent with previous
research, this study suggests that low impact activities may be an
appropriate mode of exercise for unfit and overweight individuals, while
higher impact activities will benefit individuals who have already achieved a
reasonable level of fitness.
The Bottom Line
Tae Bo can be an effective and beneficial cardiovascular workout when
performed correctly by the right type of person. Individuals who do not
frequently exercise, are overweight, are over the age of 50, or have health
problems should opt for a lower impact form of exercise at least initially.
Tae Bo and other high impact exercises may lead to muscle damage, prolonged
loss of strength, decreased immune function, and in extreme cases
rhabdomyolysis. Susceptibilities to these negative consequences can all be
reduced however, if proper precautions are exercised. Even for those who are
extremely fit and active, unfamiliar exercise can cause damage. After
working to obtain a reasonable level of fitness, participants should begin
very slowly and master the basic Tae Bo maneuvers before participating in a
full length workout. To decrease the chances of muscle damage, participants
should work to maintain good flexibility, and perform specific warm_up and
cool_down exercises for the principal muscle groups (Mchugh, 1999). In
addition, participants should practice proper nutrition and supplement their
diets with additional carbohydrates before and after hard workouts.
When done properly, Tae Bo can increase lean body mass,
decrease body fat, improve coordination and flexibility, and in
some participants even increase the mineral content of the bones.
The novelty of Tae Bo can provide motivation and encourage
perseverance that may be absent with more traditional monotonous
workouts. So by all means, if youíre fit, healthy, and up for a
challenge, join the nearly two million other Americans who have
jumped on the Tae Bo bandwagon, just donít expect to be kicking
like Billy Blanks for quite some time.
Bassey, E., Rothwell, M., Littlewood, J., & Pye, D. (1998). Pre_ and
post_menopausal women have different bone mineral density responses to the
same high_impact exercise. Journal of Bone and Mineral Research, 13(12),
Foley, J., Jayaraman, R, Prior, B., Pivarnik, J., & Meyer, R. (1999). MR
measurements of muscle damage and adaptation after eccentric exercise,
Journal of Applied Physiology, 87(6), 2311_2318.
Grant, S., Davidson, W., & Wilson, J. (1998) A comparison of physiological
responses and rating of perceived exertion between high_impact and
low_impact aerobic dance sessions. European Journal of Applied Physiology
and Occupational Physiology, 78(4), 324_332.
McHugh, Mal. (1999) Can exercise induced muscle damage be avoided? The
British Journal of Sports Medicine, 33(6), 377.
Morris, F., Naughton, G., Gibbs, J., Carlson, J., & Wark, J. (1997).
Prospective ten_month exercise intervention in premenarcheal girls: Positive
effects on bone and lean mass. Journal of Bone and Mineral Research, 12(9),
Pedersen, B., Bruunsgaard, H., Jensen, M., Krzywkowski, K., & Ostrowski, K.
(1999). Exercise and immune function: effect of aging and nutrition.
Proceedings of the Nutrition Society, 58, 733_742.
Sayers, S., Clarkson, P., Rouzier, P., & Kamen, G. (1999). Adverse events
associated with eccentric exercise protocols: six case studies. Medicine and
Science in Sports and Exercise, 31(12), 1697_1702.
Psychology DepartmentThe Health Psychology Home Page is produced and maintained by David Schlundt, PhD.
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