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Strength Training


What Is Strength Training?

Strength training is a way to build muscles and strength using free weights, weight machines, and rubber resistance bands, or body weight. Kids and teens may want to do strength training to improve sports performance, treat or prevent injuries, or improve their appearance.

What Are the Benefits of Strength Training?

Strength training can help kids and teens build strong muscles. With a well-designed and supervised program, they can:

  • improve overall fitness and sports performance
  • increase lean body mass (more muscle, less fat)
  • burn more calories
  • make bones stronger
  • improve mental health

Who Can Do Strength Training?

Kids and teens who are ready to participate in organized sports or other activities such as baseball, soccer, or gymnastics usually can safely start strength training. Kids as young as 7 or 8 years old can safely do strength training if they have good balance and control of their body, follow instructions, and can do the exercises with good form.

A child's strength-training program shouldn't be a scaled-down version of an adult's weight training regimen. Kids who strength train should learn proper technique and know how to use the equipment safely.

Trainers who work at schools, gyms, and in weight rooms know about strength training. But look for someone who is a certified strength-training expert and who has experience working with kids and teens.

Is Strength Training Safe?

Strength-training programs are generally safe. When done properly, strength training won't damage growing bones.

As with any sport, talk to your doctor before letting your child start a strength-training program. Kids and teens with some medical conditions — such as uncontrolled high blood pressure, seizures, heart problems, and other conditions — need their doctor's OK before they start strength training.

Also, your child should be closely supervised and using the right equipment and proper technique.

The best way to learn proper technique is to do the exercises without any weight. When technique is mastered, weight (or resistance, if using exercise bands) can be added, as long as your child can comfortably do the exercise for 8 to 15 repetitions with good form. Kids should not use machines and equipment designed for adults.

Most injuries happen because a child was goofing around and not supervised. Muscle strains are the most common injury associated with strength training.

Some young and professional athletes try anabolic steroids and other performance enhancers to build muscles and improve athletic performance and appearance. Talk to your child about the dangers of using these drugs.

What's a Healthy Routine?

In general, kids and teens should tone their muscles using light weights (or resistance) and a high number of repetitions rather than lifting a heavy load once or twice.

The amount of weight will depend on a child's age, 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 comfortably at least 8 times, the weight is too heavy.

Preteens shouldn't be concerned about adding muscle bulk, which won't happen until after they've gone through puberty. After puberty, the male hormone helps build muscle in response to weight training. Boys have more testosterone than girls do, so they get bigger muscles.

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.
  • Warm up with at least 5–10 minutes of activity and dynamic stretching. Cool down with less intense activity and static stretching.
  • 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 can start with body weight exercises (such as sit-ups and push-ups) and work on technique without using weights. When proper technique is mastered, a relatively light weight can be used with a high number of repetitions (8–15). Increase the weight, number of sets, or types of exercises as strength improves.
  • For best results, do strength exercises for at least 20–30 minutes 2 or 3 days per week. Take at least a day off between sessions.

Strength training is one part of a total fitness program. Kids and teens should get at least an hour a day of moderate to vigorous physical activity every day, including aerobic (cardio) activity, like running, biking, and playing outside. Also, be sure you child drinks plenty of liquids and eats a healthy diet for better performance and recovery.

Reviewed by: Mary L. Gavin, MD
Date reviewed: August 2018

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