Safe Weight Loss and Weight Gain (Care of the Young Athlete)

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Many athletes actively seek changes in body
weight in hopes of improving athletic performance. In some sports, such as
wrestling, gymnastics, dancing, and running, athletes and coaches associate
optimal performance with a relatively low body mass. In other sports,
particularly contact and collision sports, such as football, increased body mass
is often encouraged.

Athletes interested in losing or gaining weight
should discuss strategies for healthy weight loss or weight gain with their
doctor. The following is information from the American Academy of Pediatrics
about healthy weight loss or weight gain for the young athlete.

Weight and age

Ages 2 to 10 years

Generally, children in this age group should
not lose weight because it can affect normal growth and development.
Concerns about weight need to be addressed with the child’s doctor.
The usual goal for children who are overweight at this stage is to maintain
weight and allow them to “grow into” their weight.

Ages 10 to 12 years

Some children in this age group will start
to grow faster as they enter puberty. The “early bloomers”
often have a temporary size and strength advantage over children who develop
later. Boys who have not yet begun puberty will sometimes try to gain weight
to keep up with their peers. However, efforts to gain weight before puberty
lead to increased fat, not muscle, and do not speed up strength and muscle

Ages 12 to 18 years

Many teens try hard to gain or lose weight
to improve how they look. Teen athletes may also want to improve their
sports performance.

Weight and sports performance

Athletes who are trying to improve sports
performance should keep the following in mind:

  • There is no single “best”
    weight for a given sport. For each athlete there is a range of healthy
    weights that allow for peak athletic performance.

  • It is often more beneficial to monitor
    athletic performance (such as strength, speed, jump height) than

  • In athletes, weight and body mass index
    (BMI) are not good indicators of body fat and lean muscle. Athletes who
    are thinking about making major changes in weight, and those who are in
    weight-classified sports (such as wrestling), should have body
    composition measurements taken to find out percentages of body fat and
    lean tissue.

  • Coaches and parents often do not realize
    the influence they have on young athletes. Even a casual weight- related
    comment from a coach might place the athlete at increased risk for
    unhealthy eating behaviors. Parents should try to be aware of
    weight-related messages their children may be receiving from

Weight loss

Athletes (and coaches) in many sports, such as
wrestling, gymnastics, dancing, and running, believe that they will perform
better if they lose weight. For athletes who are above their healthy weight,
losing excess body fat may be beneficial. However, weight loss in athletes who
are already at a healthy weight is not likely to improve performance. Also, most
diets that limit calories often result in decreased training intensity and peak

For the athlete who wants to lose weight in a healthy way, the following
tips may be helpful:

  • Do not lose more than 1 to 2 pounds per
    week. Anything faster than this is often due to loss of muscle tissue or
    water (both of which are important for athletic performance).

  • Weight loss efforts should combine
    changes in athletic training and diet.

  • Cycles of weight loss and gain should be
    avoided. This leads to decreases in metabolism and calorie

  • Weight loss can be difficult and
    frustrating. Young athletes who wish to lose a lot of weight should talk
    with their doctor first.

Weight gain

Athletes in some sports, such as weightlifting
and football, think that strength, power, and sports performance will get better
if they are able to gain weight. However, it is important to remember that
weight gain can come from increases in either fat or muscle. Increases in muscle
may be very helpful for some young athletes, but increases in fat may result in
decreased sports performance. Unfortunately, it is much easier to gain fat than
muscle. Young athletes should be encouraged to make changes that will help with
improving strength, rather than just gaining weight.

For the athlete who wants to gain lean muscle in a healthy way, the
following tips may be helpful:

  • Gain only 1 to 2 pounds each week. Gains
    faster than this often lead to greater increases in fat.

  • Increase calories by 300 to 400 calories
    each day. Two servings of instant breakfast or meal replacement products
    can be one option. (Note: “Weight gainer” supplements
    often contain too many calories and cause greater increases in fat than
    in muscle.)

  • Eat every 2 to 3 hours, or about 5 to 9
    times per day.

  • Weight lifting should be done in sets of
    8 to 15 repetitions for muscle growth, or in sets of 4 to 6 repetitions
    to develop strength and power.

  • There should be at least 48 hours
    between hard workouts. This allows muscles to recover between training

  • Increases in weight and muscle size tend
    to become much easier during puberty.