View trusted insights from KidsHealth.org, the No. 1 most-viewed health site for children, created by the experts at Nemours. We've also provided information from the most-respected nonprofit organizations.
From Nemours' KidsHealth
- Strength Training
- Feeding Your Child Athlete
- Competitive Sports: Helping Kids Play it Cool
- Sports Physicals
- Preventing Children's Sports Injuries
- Concussions Special Needs Factsheet
- Medial Collateral Ligament (MCL) Injuries
- Jumper's Knee (Patellar Tendonitis)
- Asthma: Exercise-Induced Asthma Special Needs Factsheet
- Asthma and Sports Special Needs Factsheet
- A to Z: Lumbago
- A to Z: Tenosynovitis
- Anterior Cruciate Ligament (ACL) Injuries
- Diabetes and Sports Special Needs Factsheet
- A to Z: Fracture, Radius
- A to Z: Fracture, Fibula
- A to Z: Fracture, Clavicle
- A to Z: Fracture, Distal Radius and Ulna
- A to Z: Fracture, Elbow
Trusted External Resources
What Is Strength Training?
Strength training is the practice of using free weights, weight machines, and rubber resistance bands, or body weight to build muscles. With resistance the muscles have to work harder to move. When the muscles work harder, they grow stronger and more efficient.
What Are the Benefits of Strength Training?
Strength training can help kids and teens build healthy muscles, joints, and bones. With a properly designed and supervised program, they can improve endurance, total fitness level, and sports performance. Strength training can even help prevent injuries and speed up recovery.
Strength training can also help fortify the ligaments and tendons that support the muscles and bones and improve bone density, which is the amount of calcium and minerals in the bone. And the benefits may go beyond physical health. Young athletes may feel better about themselves as they get stronger.
Who Can Do Strength Training?
Kids and teens who are ready to participate in organized sports or activities such as baseball, soccer, or gymnastics usually can safely to start strength training.
A child's strength-training program shouldn't just be a scaled-down version of an adult's weight training regimen. A trainer who has experience in working with kids should design a program for your child and show your child the proper techniques, safety precautions, and how to properly use the equipment.
Kids as young as 7 or 8 years old can usually do strength-training activities (such as pushups and sit-ups) as long as they show some interest, can perform the exercises safely, and follow instructions. These exercises can help kids build a sense of balance, control, and awareness of their bodies.
Specific exercises should be learned without resistance. When proper technique is mastered, small amounts of resistance (body weight, band, or weight) can be added. In general as kids get older and stronger, they can gradually increase the amount of resistance they use. A trained professional can help your child determine what the appropriate weight may be.
Is Strength Training Safe?
As with any sport, it's a good idea to have your child visit a doctor before beginning a strength-training regimen. Then, make sure that your child is properly supervised, uses safe equipment, and follows an age-appropriate routine.
Muscle strains are the most common form of injury, and the lower back is the most commonly injured area. But these injuries usually happen because the child has not used the proper lifting technique or is trying to lift too much weight.
As long as your child is using the proper techniques and lifting an appropriate amount of weight, strength training shouldn't have any effect on growth plates, the layer of cartilage near the end of the bone where most of the bone growth occurs.
Strength training should not involve the use of anabolic steroids. Some young and professional athletes have abused these drugs to build muscles and improve athletic performance and appearance. But these drugs, some of which are illegal, can pose severe risks to physical and psychological health.
A Healthy Routine
In general, kids and teens should tone their muscles using a low amount of weight and a high number of repetitions, instead of trying to lift a heavy load one or two times.
The amount of weight will depend on a child's current size and strength level. But in general, kids should be able to lift a weight with proper technique at least 8 to 15 times. If they can't lift the weight at least 8 times, the weight is too heavy.
Preteens shouldn't be concerned about adding muscle bulk, which won't occur until after they have passed through puberty. Even then, it's important to focus on technique so that they can strengthen their muscles safely.
The focus of each training session should be on proper form and technique, with qualified instruction and supervision.
Strength Training Program Guidelines
Here are some guidelines when considering strength-training programs:
- An instructor-to-child ratio of no more than 1 to 10.
- The instructor should have an approved strength-training certification and experience with kids and strength training.
- When teaching a new exercise, the trainer should have kids perform the exercise under his or her supervision in a hazard-free, well-lit, and adequately ventilated environment.
- Warm up with at least 5–10 minutes of aerobic activity and dynamic stretching. Cool down with less intense activity and static stretching.
- Calisthenics and stretching exercises should be performed before and after strength training.
- Kids should begin with one set of 8–15 repetitions of 6–8 exercises that focus on the major muscle groups of the upper and lower body and core.
- Kids should start with no load (resistance). When proper technique is mastered, a relatively light weight can be used with a high number of repetitions. Increase the weight as strength improves. Progression also can be achieved by increasing the number of sets (up to three) or types of exercises.
- Two to three training sessions per week on nonconsecutive days is sufficient.
It's important to remember that strength training is one part of a total fitness program. It can play a vital role in keeping your child healthy and fit, along with aerobic exercise such as biking and running, adequate hydration, and healthy nutrition.
Reviewed by: Mary L. Gavin, MD
Date reviewed: August 21, 2017