Wayne L. Westcott: Strength training provides a lift for overweight children
We are presently experiencing an epidemic of youth obesity in both elementary and secondary school students.
There are two primary reasons for children adding too much weight. First, many boys and girls are eating foods that are high in empty calories and low in essential nutrients. Second, most young people spend most of their time sitting (school, television, computers, movies, etc.) and too little time with physical activities.
Parents, teachers and other influential individuals need to ensure better food choices and more exercise. However, there are two other contributing factors that may be equally problematic.
One is too little sleep, which is almost universal among pre-teens and teenagers. There is a strong relationship between insufficient sleep and weight gain, as appropriate amounts of sleep are necessary for facilitating desirable body functions, including healthy appetite and performance energy.
The second factor is that only a small percentage of young people perform regular resistance exercise to develop a strong musculoskeletal system and maintain a high metabolic rate while resting.
Unlike previous generations of boys and girls, today’s children are typically too heavy to lift their own bodyweight. You rarely see youth climbing trees, using playground equipment or even jumping rope. Calisthenics, such as sit-ups, push-ups, pull-ups and dips, are too challenging for overweight pre-adolescents.
If excess body fat prevents young people from performing calisthenics, what can they do to enhance their muscular strength and endurance? They can use external resistance, such as free weights and resistance machines, which enable muscles to work against appropriate levels of resistance rather than bodyweight resistance.
For example, Billy may not be able to perform a pull-up with his 100-pound bodyweight, but he may perform 10 pull-downs with 50 pounds on the pull-down machine, which works the same muscle groups. When he is capable of completing 15 repetitions with 50 pounds, he may increase the pull-down resistance to 55 pounds.
The advantages of training with external resistance include the ability to gradually increase the resistance (1 to 5 pounds) as one becomes stronger.
Our 20 years of youth strength training research finds that most boys and girls respond favorably to progressive resistance exercise programs. On average, our preadolescent participants at the South Shore YMCA in Quincy, Ill., increased their muscle strength by 45 to 65 percent in 10 weeks of training, which enhanced their self-confidence and increased their physical activity time and sports team involvement.
Although not as likely to participate in organized athletics, our overweight and obese children were just as enthusiastic about strength training as our more fit class members. One reason for their positive attitude was the reinforcement of experiencing progress in the resistance exercises. Most participants increased either the exercise repetitions or the exercise weight every training session, which is highly motivating for youth who have had little prior success in physical activities.
Another reason was that the heavier preadolescents could actually lift as much or more weight than their lighter peers. Although they were not as strong on a pound-for-pound basis, this was the first physical activity in which they were performing on par with their fellow students.
A third reason was the camaraderie among all class members, who always trained cooperatively rather than competitively. They understood that individual progress was the primary program objective. The average completion and attendance rate for our youth strength training class members was greater than 95 percent.
We found that preadolescents responded best to a basic and brief strength training program sandwiched between a warm-up period and cool-down period of general physical activities. The physical activity periods included various locomotor movements (hopping, skipping, jumping, running, etc.) and ball handling skills (throwing, catching, kicking, dribbling, etc.), as well as many types of non-competitive relays and games.
Our strength training programs required one set of 10 child-size resistance machines that cumulatively addressed most of the major muscle groups (leg extension, leg curl, leg press, chest cross, chest press, lat pull-down, seated row, shoulder press, biceps curl and triceps extension) and two bodyweight exercises (trunk curls and trunk extensions).
The kids used a resistance that permitted 10 to 15 repetitions (using controlled movement speed and full movement range). As with our adult programs, we have had equally good results with two and three strength training sessions a week (always on non-consecutive days to permit sufficient recovery time).
Because children are experiencing daily growth, development and maturation processes, they respond very well to relatively short strength training sessions. The youth in our studies increased their muscle tissue by an average of 2 1/2 pounds by performing just 20 minutes of strength training twice a week for 10 weeks.
Wayne L. Westcott, Ph.D., teaches exercise science at Quincy (Mass.) College and consults for the South Shore YMCA. He has written several books on youth fitness and preadolescent strength training.