As a boy, I generally liked physical education class exercises. I was
not, however, fond of fitness testing day. Like 50 percent of all
young people then and now, I could not chin myself and always felt
embarrassed struggling to lift my body weight. It was always
interesting to me that this all-out, gut-wrenching muscular effort was
considered good but that any form of weight training was considered
bad.
Several years later when I became the physical education teacher in
that same elementary school, we did things differently. I developed
an after-school weight training program for the fifth and sixth
graders where the students progressively increased their muscular
strength. We had no injuries, and very few program participants ever
failed the chin-up test.
This took place in the early 1970s, when the prevailing
misunderstanding was that youth strength training was either dangerous
or worthless. Many feared that lifting weights would damage bone
growth plates. Others felt strength training was useless because
young muscles did not have the capacity to gain strength apart from
normal growth processes.
Both assumptions have proven false. According to the National
Strength and Conditioning Association, there are no documented reports
of bone growth plate injury due to sensible strength training.
Several research studies have also demonstrated that boys and girls
can gain muscle strength at about the same rate as adults. During the
past three years, we at South Shore YMCA have completed five youth
strength training studies. All were conducted by certified strength
instructors over a two-month training period.
Study One
The first study (Westcott 1991) was conducted with teenage boys and girls. The training group consisted of 14 exercisers, and the control group consisted of five non-exercisers, both with an average age of 14 years. The exercise group trained three days per week for eight weeks, using eight upper and lower body machines. The participants performed one set of eight to 12 repetitions with each exercise, using slow movement speed and full movement range.
The exercise group increased their lower body strength by 63 percent and their upper body strength by 33 percent. By comparison, the non-exercise group improved their lower body strength by 8 percent and their upper body strength by 4 percent.
Both groups experienced a 3-pound increase in body weight over the two month study period. The exercisers added 4 pounds of lean weight and lost 1 pound of fat weight, whereas the non-exercisers added 2 pounds of lean weight and 1 pound of fat weight. Although the control group added lean tissue through normal growth processes, they did not improve their functional muscle strength significantly. However, the exercise group added twice as much lean tissue and made significant improvements in their functional muscle strength.
Study Two
This study (Westcott 1992) involved 10 pre-adolescent boys and girls, with an average age of 10 years. All of the participants trained three days per week for eight weeks with the following machines: leg extension, leg curl, chest press, biceps curl and shoulder press. They performed one set of eight to 12 repetitions with each exercise, using slow movement speed and full movement range.