Is Strength Training Safe for Kids & Teens?

Written by Kate Bunten

It is a commonly held belief among many adults that children and adolescents* should avoid strength training** due to fears over safety and the risk of stunting growth. But is this really the case?

In this blog, I will explore what the current evidence says about strength training during adolescence and childhood, unpack some common myths, compare the risks and benefits of strength training, and provide some recommendations for getting started.

Throughout this piece I draw largely from the 2020 journal article published in the American Journal of Paediatrics, Resistance training for Children and Adolescents (1) which provides an updated and comprehensive summary of research in this area.

* Children – Individuals 12 and under; Adolescents – Individuals 12-17 years

** I use the terms Weight training; Strength training and Resistance training interchangeably throughout the blog to refer to exercise in which the body is worked against some form of resistance (bodyweight or external load) with the aim of improving muscular capacities in strength, endurance and/or power.

Resistance Training: Myths & Facts

MYTH 1 Weight training in children or adolescents can stunt their growth by damaging their unsealed growth plates.

FACT ~ Multiple studies have demonstrated that resistance training (with or without added external load), when appropriate programmed and supervised, has no negative impact on growth or the development of the musculoskeletal system, including no damage to growth plates demonstrated. (1,3)

MYTH 2 ~Weight training is dangerous for children/ adolescents with high risks of injury.

FACT ~ Studies reviewing the incidence of injury in kids and adolescents across a wide range of sports and recreational activities found that risk and occurrence of injury was in fact lower for strength training compared to many other sports (soccer, basketball etc.) and non-organised forms of play (playgrounds, climbing trees etc.) (1)

According to data accrued by the American National Electronic Injury Surveillance System (NEISS) injuries that did occur with resistance training mostly involved unsafe use of equipment, in a home gym setting with lack of supervision.(1)Appropriately programmed resistance training with a focus on proper technique and with sufficient supervision by a knowledgeable professional is a relatively low risk form of exercise AND can aid in injury risk reduction in other sports played by the individual (more to come on this below). (1)

MYTH 3 ~ Children/ Adolescents will get “bulky” or slow from resistance training

FACTS ~ Due to specific hormone levels around puberty (such as low testosterone in both boys/ girls) any hypertrophic effect (bulking up/ growing muscle size) from weight training is very limited in these age groups. Strength improvements demonstrated are primarily due to neuromuscular adaptations (improved coordination between the nervous system and muscular system) that allow for greater muscle fibre recruitment, as opposed to increasing the size of the muscle fibres. (1,3)

So, why should children/ adolescents partake in resistance training?

Some of the benefits of resistance training in children & adolescents are:

  • Improvements in overall health including cardiovascular fitness, increased bone density & improved blood health (1)
  • Positive impacts on mental health and self-esteem (2)
  • Reduction in injury risk in sports and/or a more successful rehabilitation from injuries that do occur (1)
  • Improved sports performance through increases in motor skill, strength, speed & power (1,3)

Unfortunately, there is growing evidence of decreasing levels of fitness, both muscular & cardiovascular, in today’s youth compared to previous generations. This is proposed to be linked to a rise in sedentary behaviours and a drop in physical play activities. Therefore, it is more important than ever to engage children & teens in different forms of movement, resistance training provides one such avenue for exercise.

But are there any risks? And if so, what are they?

There is always some degree of risk involved with any activity, and strength training is no exception. Most injuries that occur in strength training occur due to:

  • Inadequate supervision
  • Inappropriate use of equipment
  • A mismatch between level of skill/ control/ strength required to complete and exercise and that possessed
  • Or, commonly, a combination of the above

By ensuring appropriate supervision, exercise selection and education, many of the risks associated with resistance training can be mitigated.

Recommendations for a safe introduction to resistance training for children/ adolescents (1)

  1. Seek out supervision/ guidance from a professional (such as a physiotherapist, exercise physiologist or strength & conditioning coach) with expertise in working with young people in a strength environment.
  2. Start with bodyweight exercises under supervision, in a safe environment. Focus on proper technique and building control with all exercises before progressing to any additional external load.
  3. Specific exercise difficulty should be kept within the physical and cognitive abilities of the specific individual, with consideration given to age and experience.
  4. To optimise desired outcomes strengthening programs should aim to be a minimum of 8 weeks with 2-3 sessions/ week (1) (this is a general guide only, training plans should always consider the context of the individual(s) involved).

To summarise, resistance training is considered a relatively safe form of exercise for teens and children with appropriate supervision and exercise selection relative to the abilities of the individual. Resistance training provides lots of benefits including improved health, performance, and reduced risk of injury in sport.

If you would like to enquire further about whether resistance training might be appropriate for your child or teen, don’t hesitate to give us a call on 9303 4111 or book online with any of our knowledgeable Physiotherapists.

References

  1. Paul R. Stricker, Avery D. Faigenbaum, Teri M. McCambridge, COUNCIL ON SPORTS MEDICINE AND FITNESS, Cynthia R. LaBella, M. Alison Brooks, Greg Canty, Alex B. Diamond, William Hennrikus, Kelsey Logan, Kody Moffatt, Blaise A. Nemeth, K. Brooke Pengel, Andrew R. Peterson; Resistance Training for Children and Adolescents. Pediatrics June 2020; 145 (6): e20201011. 10.1542/peds.2020-1011
  2. Granacher U, Lesinski M, Büsch D, et al. Effects of Resistance Training in Youth Athletes on Muscular Fitness and Athletic Performance: A Conceptual Model for Long-Term Athlete Development. Front Physiol 2016;7:164. 10.3389/fphys.2016.00164
  3. Myers AM, Beam NW, Fakhoury JD. Resistance training for children and adolescents. Transl Pediatr. 2017 Jul;6(3):137-143. doi: 10.21037/tp.2017.04.01. PMID: 28795003; PMCID: PMC5532191.