Strength training for kids offers many benefits. Along with building strength, body weight and resistance exercise can improve bone mineral density, body composition, self-esteem, balance, and cholesterol levels. "Strength training, when done correctly, can improve the strength, and overall health of children and adolescents of all athletic abilities," said Katherine Stabenow Dahab, MD, who did a comprehensive review of scientific research on the topic (published in the journal Sports Health). Strength training can improve your athlete's performance in the sport of her choice. It can also boost metabolism, and help your child reach a healthy weight and maintain it.
There are risks associated with strength training, such as growth-plate fractures and lower back injuries. However, "the health benefits of strength training far outweigh the potential risks," Dahab said.
When Should Strength Training for Kids Start?
Even preschoolers (ages 3 to 5) can strength train, although this does not mean they should be lifting weights. Instead, they can do simple exercises that use body weight as resistance—and are fun too. Try cobra push-ups, for example: Kids start face-down on the floor, with hands underneath the shoulders and elbows bent. Then they push up, lifting their heads and chests up and forward (but keeping hands, forearms, bellies, and legs on the floor).
Between ages 6 and 9, kids can begin to use equipment to add resistance beyond their own body weight. Try resistance bands or tubes, or light medicine balls or hand weights. (You can also make your own hand weights with household items.) The American Academy of Pediatrics has developed a strength training for beginners app for iPod, iPhone and iPad. It's called IronKids and it include demos of exercises for the core, upper body and lower body. You can also use the app to create custom workouts and set goals and reminders.
After puberty, muscles can begin to bulk up as a result of strength training. At this age, kids need to be educated about the dangers of anabolic steroids. Steroids are illegal and dangerous, and other supplements—even herbal ones touted as "safe"—may be too.
Safe Strength Training for Kids
At all ages, emphasize slow, controlled movements and proper form. The idea is to make muscles stronger, not necessarily bigger (like bodybuilders do). Before encouraging your child to strength train, make sure he is mature enough to follow directions and perform movements safely.
Kids and teens should follow a personalized strength training program based on their age, maturity, and goals (such as strengthening muscles they use for other sports). Get advice from a trainer or coach who has experience with kids your child's age. A comprehensive routine should include:
- Adult supervision (always!)
- 5 to 10 minutes of warm-up (for example, walking or jumping rope)
- Exercises using a variety of resistance equipment (free weights, weight machines, medicine balls, resistance bands/tubes)
- Two to three exercises for each major muscle groups (arms, shoulders, legs, abdomen, upper and lower back, chest)
- Exercises that encourage a balance between flexing and extending the joints
- Weight/resistance that allows for 10 to 15 repetitions in each set; a trained professional should teach proper form, and help kids learn how and when to add more weight
- 5 to 10 minutes of cool-down and gentle stretching
Dahab MD, Katherine Stabenow, and McCambridge MD, Teri Metcalf. Strength Training in Children and Adolescents: Raising the Bar for Young Athletes? Sports Health: A Multidisciplinary Approach, May/June 2009 vol. 1 no. 3.