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Healthy
Weight Journal July/August 2000 Vol. 14 #4
Rapid
weight loss
involves
risk
by Sheri Albert,
MPH, RD
Rapid weight loss can hurt performance and endanger the
health of athletes. Although most health professionals discourage "weight
cutting" or "making weight," it is common among athletes competing in sports
that have weight classifications.1 Health providers
can play a major role in curtailing the damage of weight cutting practices
by emphasizing the "minimal competition weight" that is safe for individual
athletes and by encouraging prudent steps to maximize recovery in the period
between weigh-in and competition.
Much of the research on rapid weight loss is with male
athletes, particularly wrestlers. However, weight cutting practices have
been observed in female rowers, body builders, and martial artists.2-4
By competing in the lowest possible weight class, the athletes aim for
a strength and leverage advantage over their smaller opponents. However,
because their desired competition weight is often far below their natural
off-season weight, many resort to drastic measures to temporarily drop
weight quickly before each competition. This is generally accomplished
by restricting food and fluid intake, sweating in a sauna, exercising vigorously
in plastic or rubber suits, and/or using diuretics, laxatives, self-induced
vomiting, or even spitting.5 Most of the
weight loss occurs in less than 10 days prior to competition, with some
research indicating as late as 2 to 3 days before an event.6
Rapid weight loss in high school and collegiate wrestlers has been shown
to average 4.4 pounds per week,7 with some
athletes losing as much as 11 to 20 pounds a week during the competitive
season.8 An athlete may drop 5 to 6 pounds
just hours before a weigh-in.9 The up and
down weight cycle is typically repeated before each competition and may
recur more than 10 times in a season.7
Rapid weight loss in athletes is largely due to reductions
in body water (dehydration), glycogen reserves, and lean body mass, NOT
fat loss. Thus, weight cutting can potentially have many negative effects
on an athlete's health and performance.
Dehydration
Moderate dehydration (up to 3-4 percent of body weight
lost) can generally be tolerated without serious health effects. But in
severe dehydration (over 5 percent of body weight lost), physiologic systems
are progressively compromised, and the risks for cardiovascular, renal,
and thermoregulatory problems, and even death, increase.9
Without sufficient fluid in the body, athletes will experience
reduced blood volumes and cardiac function (e.g., higher heart rate, smaller
stroke volume, and reduced cardiac output), decreased renal blood flow
and renal filtration, and reduced sweating and blood flow to the skin to
cool the body. Three cases of dehydration- and hyperthermia-related deaths
have recently been reported involving collegiate wrestlers who had lost
approximately 15 percent of their total body weight and were competing
at 25 to 37 pounds below their preseason weight.10
As for performance, dehydration of as little as 1 to 2
percent of body weight has been shown to impair muscle endurance, likely
due to the adverse changes in cardiac output.11
However, these adverse effects do not seem to impair muscle strength during
high-power exertions lasting less than 30 seconds. In fact, for athletes
participating in brief-duration, high-power sports, rapid weight loss may
give them an advantage by increasing power on a pound for pound basis.
But, as strenuous exercise is prolonged, environmental temperatures rise,
and degree of dehydration increases, performance will ultimately suffer.11
In addition, electrolyte losses may occur with large fluid losses or diuretic
use, which could further affect muscle function, resulting in impaired
coordination on increased muscle cramping.9
Depleted energy reserves and lean body mass
Food restriction reduces muscle and liver glycogen stores,
which can affect all aspects of physical performance. For example, it reduces
muscle endurance capacity and high-intensity power, impairs the body's
ability to maintain blood glucose levels (thus leading to fatigue, lightheadedness,
and difficulty concentrating), and accelerates the breakdown of the body's
protein.9 Some studies have shown retarded
growth of lean tissues in wrestlers during their season and, as a result,
reductions in muscle strength and endurance after following a weight loss
diet for as few as 3 days.9 Maintaining
a high-carbohydrate diet (65-70 percent of total calories) during periods
of negative energy balance may help prevent declines in high intensity
power, possibly by minimizing the loss of muscle glycogen.12
Other effects
Although the scientific data are not conclusive, rapid
weight loss may also alter hormonal status, impede normal growth and development,
slow resting metabolic rate (thus making rapid regain of weight more likely),
affect psychological state and cognitive function, impair academic performance,
and have more severe consequences such as pulmonary emboli, pancreatis,
and reduced immune function.7,9,13
In women, overtraining coupled with undereating to "make
weight" often results in menstrual irregularities and may increase the
vulnerability to developing disordered eating. However, it is unclear whether
the disordered eating behaviors, so commonly seen in female athletes attempting
to cut weight, persist and develop into full-blown eating disorders after
the competition is over. Many male wrestlers, for example, have a disordered
eating pattern, but very few have an eating disorder.14
Minimal weight
To limit damaging weight cutting practices in wrestling,
the American College of Sports Medicine recommends that each state implement
rules requiring (1) body composition assessment prior to the competitive
season to determine an athlete's minimal competition weight and (2) nutrition
education programs for coaches and athletes about sound weight loss behaviors.7
Dietitians, team physicians, coaches, athletic administrators, trainers,
and other health professionals can collaborate with high school and collegiate
athletes to implement these recommendations in all weight class sports.
An athlete's minimal body weight can be calculated from
body composition. Female athletes should not drop below about 14 percent
body fat.7 This is higher than the minimums
for male athletes (5 percent for 16 years or older; 7 percent if younger).
Female athletes may need to be reminded of the physiologic differences
that require women's bodies to have more fat than men's. Skinfold measurement
techniques are more useful than bioelectrical impedance analyzer systems,
which tend to overestimate percent body fat in lean individuals and give
a minimal weight that is below safe levels.10
Minimal weight is not the same as optimal weight. Optimal
weight is a weight that promotes both good health and performance and is
reasonable to achieve and maintain. If an athlete insists on reducing body
weight below the optimal level, weekly losses should not exceed 2 to 3
lb.4
Maximizing recovery
Athletes who participate in rapid weight loss practices
hope to replenish body fluids, electrolytes, and glycogen in the brief
period (30 minutes to 20 hours) between the weigh-in and competition by
immediately "bingeing" on food and beverages. However, re-establishing
fluid homeostasis may take 24 to 48 hours, replenishing muscle glycogen
may take as long as 72 hours, and replacing lean tissue might taken even
longer.7 Further, the greater the amount
of dehydration, the harder it is to refeed without gastrointestinal upset.5
Digestion requires a lot of water. The body normally produces 2 liters
of gastric juice a day, which is almost all water. Refeeding without adequate
water can lead to stomach upset, diarrhea, vomiting, and gas pains. This
discomfort can impair athletic performance.5
Despite these limitations, an athlete who has 5 hours
or more between weigh-in and competition can experience significant recovery.5
Health providers working with these athletes should keep the following
tips in mind:
-
Drink first, eat second. Eating delays the rehydration process and
increases the athlete's risk for gastrointestinal upset. Encourage the
athlete to drink a well-formulated sports beverage to provide calories
and carbohydrate along with fluid. The beverage should be slightly cooler
than room temperature (60-700F) to enhance absorption and should
be consumed in small amounts. Advise the athlete to start with 16 to 20
ounces, and then drink 4 ounces every 10 to 15 minutes to minimize nausea
and vomiting.
-
Consume high-carbohydrate foods. Liquid meals are often the best
choices. These are quickly digested and well tolerated, and most are low
in fat and high in carbohydrate. Studies have shown that athletes recover
better if they consume a high-carbohydrate (75 percent) formula diet after
a period of rapid weight loss.15
-
Be aware and develop a routine. Encourage athletes to keep track
of how many pounds they lose, over what period of time, and with which
methods and also to note which foods or beverages they consume after weigh-ins,
how well they tolerate them, and how strong they feel during competition.
This will help determine the best refeeding regimen for the athlete.
Proceed with caution
Rapid weight loss is not recommended. It can hurt performance
and endanger the health of athletes. Nonetheless, weight cutting remains
popular in many sports. The negative health and performance effects associated
with rapid weight loss can be reduced with expert advice about determining
an athlete's minimal competition weight, reasonable guidelines for achieving
this weight goal, and practical tips for maximizing recovery between the
weigh-in and competition. Although some studies are available on the prevalence
and methods of weight cutting among female athletes, more research is needed
into the short- and long-term physiologic and psychological consequences
of these practices in women.
Sheri Albert, MPH, RD, is a nutritionist at the UCLA
Arthur Ashe Student Health and Wellness Center. She teaches courses in
basic, human nutrition and sports nutrition for UCLA Extension's Fitness
Certificate Program. She can be reached at [email protected].
References
1. Horswill CA. Does rapid weight loss by dehydration
adversely impact high power performance? Sports Science Exchange 1991;4(1):30.
2. Sykora C, Grilo CM, Wilfley DE, Brownell KD.
Eating, weight, and dieting disturbance in male and female lightweight
and heavyweight rowers. Int J Eat Disord 1993;14:203-211..
3. Clark N. Nutritional concerns of female athletes:
a case study. J Sports Nutr 1991;1:257-264.
4. Rosenbloom CA. Sports nutrition: a guide for
the professional working with active people. 3rd Ed. Chicago: Sports, Cardiovascular,
and Wellness Dietetic Practice Group, The American Dietetic Association,
2000.
5. Reimers KJ, Gradjean AC. Recovering from
rapid weight loss. Strength and Conditioning 1997;19:14-17.
6. Tipton CM. Making and maintaining weight for
interscholastic wrestling. Sports Science Exchange 1990;3(2):22.
7. American College of Sports Medicine. Position
stand on weight loss in wrestlers. Med Sci Sports Exerc 1996;28:8x-xii.
8. Steen SN. Nutritional concerns of athletes who
must reduce body weight. Sports Science Exchange 1989;2(10):20.
9. Clarkson P, Manore M, Oppliger B, et al. Methods
and strategies for weight loss in athletes. Sports Science Exchange Roundtable
1998;9(1):31.
10. Luttermoser G, Gochenour D, Shaughnessy
AF. Determining a minimum wrestling weight for interscholastic wrestlers.
J Fam Pract 1999;48:208-212.
11. Lamb DR, Shehata AH. Benefits and limitations
to prehydration. Sports Science Exchange 1999;12(2):73.
12. McMurray RG, Proctor CR, Wilson W. Effect of
caloric deficit and dietary manipulation on aerobic and anaerobic exercise.
Int J Sports Med 1991;12:167-172.
13. Choma CW, Sforzo GA, Keller BA. Impact of rapid
weight loss on cognitive function in collegiate wrestlers. Med Sci Sports
Exerc 1998;30:746-749.
14. Dale KS, Landers DM. Weight control in wrestling:
eating disorders or disordered eating? Med Sci Sports Exerc 1999;31:1382-1389.
15. Walberg-Rankin J, Ocel JV, Craft LL.
Effect of weight loss and refeeding diet composition on anaerobic performance
in wrestlers. Med Sci Sports Exerc 1996;28:1292-1299.
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