Does lifting weights inhibit growth in kids?

Question

I have a teenager at home, who is itching to pull weights in a gym. He is training to be a sprinter, so I see the benefits of power and strength training, but am worried, as these are his growing years.

I have read both sides of the story: from many online websites like this, this and this answer on quora which deem it perfectly safe. However, there are research publications (like this, this and this) cautioning (thought not conclusively) about injuries due to kids' weak skeletal structure.

Are there any authoritative answers, or experiences to confirm/debunk these arguments?

Answer 1

Strength training programs including the use of free weights, weight machines, elastic tubing, or body weight is recommended to preadolescents above the age of 8 years and adolescents with reference to American Academy of Pediatrics Committee on Sports Medicine and Fitness and UK Strength and Conditioning Association on youth resistance training provided that proper technique and strict/appropriate supervision is followed. Caution should be exercised before starting exercises for youngsters with cardiac problems, seizure disorders and youngsters who have received chemotherapy with anthracyclines.

The answer to the OP's question lies in the AAP 2008 policy statement itself.

1. According to American Academy of Pediatrics Committee on Sports Medicine and Fitness, strength training with proper technique and strict/appropriate supervision can increase strength in preadolescents and adolescents. However, it should be also noted that gains in strength, muscle size, or power are lost close to 6 weeks after resistance training is discontinued.

2. Appropriate strength-training programs with proper technique and strict supervision have no apparent adverse effect on linear growth, growth plates, or the cardiovascular system.

3. Caution should be exercised for youngsters with preexisting hypertension, youngsters who have received chemotherapy with anthracyclines due to increased risk for cardiac problems because of the cardiotoxic effects of the medications and youngsters having seizure disorders. These susceptible populations would require medical clearance before starting resistance training.

4. Preadolescents and adolescents should avoid power lifting, body building, and maximal lifts until they reach physical and skeletal maturity. Strength programs are recommended not to start before balance and postural control skills maturity to adult levels by 7 to 8 years of age. Preadolescents and adolescent should also completely avoid performance-enhancing substances or anabolic steroids for exercising.

Research indicates that resistance training can offer unique benefits for children and adolescents when appropriately performed and supervised when one refers to the official position statement of the UK Strength and Conditioning Association on youth resistance training reviewed and endorsed by leading professional organisations within the fields of sports medicine, exercise science and paediatrics such as paediatric exercise science, paediatric medicine, physical education, strength and conditioning and sports medicine in 2014.

1. The use of resistance training by children and adolescents is supported on the provision that qualified professionals design and supervise training programmes that are consistent with the needs, goals and abilities of younger populations.

2. Resistance training prescription should be based according to training age, motor skill competency, technical proficiency and existing strength levels. Qualified professionals should also consider the biological age and psychosocial maturity level of the child or adolescent.