PREPUBESCENT RESISTANCE TRAINING IS DANGEROUS AND STUNTS GROWTH
Many parents want to do whats best for their children. Whether to help them be more healthy or to achieve improved athletic performance, a common question is whether or not children can and should participate in resistance training. Many parents have expressed to me their concern of whether or not resistance training is safe while others have heard rumors that resistance training at a young age will stunt the growth of the child. I lump these two points of concern together since I believe that they have some areas that will blend together and can be answered semi-simultaneously and fluidly.
It should be pointed out that this article is specifically referring to prepubescent children. This is the time period in life after infancy but before we develop our secondary sex traits. Puberty will have individual variances but generally occurs around 13 years old for boys and 11 years old for girls (Faigenbaum et al., 2009). Although infancy can be defined to end as early as 1 year old, this article in no way suggests that this is an appropriate starting age. Rather, a child needs to demonstrate sufficient understanding and awareness of their body as well as enough maturity to comprehend the potential dangers of resistance training if not performed properly. Anecdotal evidence has led me to believe that this occurs between the ages of 6-8 for many children. Faigenbaum et al. (2009) also suggest seeking the opinion of a doctor for children with a history of injury or disease. Working under these defined parameters of children who are as young as 6 years old and up until they reach puberty, we will explore the common parental concerns for safety and growth.
Faigenbaum et al. (2009) theorize that some of today’s misguided concern for the safety of youth resistance training could stem from a collection of data from the National Electronic Injury Surveillance System (NEISS). The NEISS collected data from various sources including emergency room departments. The problem is that any injury that involved resistance training was implied to be due to resistance training itself with no contextual information. Truly, many of the reported injuries could have been avoided if the participants had been following proper resistance training etiquette or safety measures.
All of life’s activities carry varying degrees of risk. The potential of injury is present in almost every movement and activity that we perform. But resistance exercise has been studied to be a low risk for injury for children who are properly supervised and assigned age-appropriate modalities and intensities (loaded weight) (Faigenbaum et al., 2009). In fact, only 3 studies have ever been published that reported an injury during the experimental phase. Rians et al. (1987) reported a shoulder strain, but the issue resolved after one week of resting. Sadres et al. (2001) reported an incident where the child presented frontal thigh pain that went away after a 5 minute break. Finally, Lillegard et al. (1997) had a participant miss a single training session due to a shoulder strain. Thus, the research demonstrating and arguing the dangers of childhood resistance training under proper circumstances aren’t there.
The safety of prepubescent resistance training should not only be explored through specific evaluation but also quantified in a comparative manner to other common activities. A study by Zaricznyj et al. (1980) looked into 1576 sports-related injuries over a 1 year time period. During this time and of the total injuries, only 0.7% were due to resistance training while basketball and football accounted for 15% and 19%, respectively. It could be argued that this low percentage could be due to the fact that there are far less children who participate in resistance training. When these values were equated for in a study by Hamill (1994) it was reported that for every 100 participants, childhood resistance training and weightlifting only presented 0.0012 injuries. Rugby was the highest, being 0.8000 injuries per 100 participants and soccer was found to have 0.014 injuries per 100 participants. In comparison to other sports/activities it can be stated that resistance training is at least as safe as popular sports, but likely more safe under proper supervision and precaution.
As a child my participation in resistance training was fairly non-existent for multiple reasons. My parents were among those to believe that pre-pubescent resistance training could stunt growth. This belief, coupled with a rule that youth under the age of 14 weren’t allowed in weight room (even supervised) at our local gym were factors that prevented my participation. The statement that childhood resistance training can stunt growth is semi-ambiguous and it is likely that few people who carry this belief understand the modality by which this could happen. Growing children have 3 main areas in which growth cartilage can be found. These sites include the points where major tendons attach to bones, the articular cartilage of joint surfaces and growth plates that are found on the ends of long bones (Faigenbaum et al., 2009). Growth cartilage is referred to as “pre-bone” and is indeed weaker than the nearby connective tissue and can become injured from repetitive traumas or dynamic accidents. Injuring these areas can lead to growth disturbances, but not always and a growth disturbance in not a permanent stunting of growth. As mentioned previously, there are only 3 studies that reported injury during their experimental phase and none of those were to growth cartilage. This is not to say that it’s never happened, and is actually reported in some studies to have occurred to pubescent lifters who were lifting improperly and/or without adult supervision (Faigenbaum et al., 2009). Interestingly, prepubescent children are less likely to incur this type of injury than pubescent youth. It is thought that this is due to growth cartilage of prepubescent children being stronger and more resistant to sheering injury than their older peers (Faigenbaum et al., 2009).
Also contrary to the belief that childhood resistance training stunts growth are findings that resistance training is great for injury prevention. Children who resistance train exhibit many phsyiological adaptations that lead to increased strength and stability that could actually help prevent an injury to growth cartilage (Faigenbaum et al., 2009). Research by Stracciolini et al. (2013) actually shows that children are more likely to incur fracturing injuries compared to pubescent children who obtain more soft tissue injuries. Children who resistance train will also see increases to bone density that will help to prevent bone fractures.
As repeatedly mentioned, proper measures need to be taken in order for prepubescent children to have safe and beneficial experiences with resistance training. Since children rely on their parents and caregivers for access to exercise equipment, supervision, nutrition, hydration and sleep habits, I cannot overly emphasize the importance of their role in the health of the child. Although not the topic of this article, there exist many differences in how a prepubescent child should train. Parents should seek out professionals who understand that children are not “small adults” and that will make appropriate adjustments to exercise selection, volume, frequency, intensity, progressive overload and who will control the environment to be well supervised and appropriate to the age of the child. It’s not enough to just “bring your child with you while you workout.” Seek the advice of someone qualified that can explain the differences between children and adult lifters and help you make an age-appropriate plan. When all considerations are taken, prepubescent children can not only perform resistance training exercises safely but will obtain many physiological and emotional improvements that can carry over into adulthood.
Faigenbaum, A. D., Kraemer, W. J., Blimkie, C. J. R., Jeffreys, I., Micheli, L. J., Nitka, M., & Rowland, T. W. (2009). Youth resistance training: Updated position statement paper from the National Strength and Conditioning Association. Journal of Strength & Conditioning Research, 23, S60–S79.
Hamill, B. P. (1994). Relative safety of weightlifting and weight training. Journal of Strength & Conditioning Research (Allen Press Publishing Services Inc.), 8(1), 53–57.
Lillegard, W. A., Brown, E. W., Wilson, D. J., Henderson, R., & Lewis, E. (1997). Efficacy of strength training in prepubescent to early postpubescent males and females: Effects of gender and maturity. Pediatric rehabilitation, 1(3), 147–157.
Rians, C. B., Weltman, A., Cahill, B. R., Janney, C. A., Tippett, S. R., & Katch, F. I. (1987). Strength training for prepubescent males: Is it safe? American Journal of Sports Medicine, 15(5), 483–489.
Sadres, E., Eliakim, A., Constantini, N., Lidor, R., & Falk, B. (2001). The effect of long-term resistance training of anthropometric measures, muscle strength, and self concept in pre-pubertal boys. Pediatric Exercise Science, 13(4), 357–372.
Stracciolini, A., Casciano, R., Levey Friedman, H., Meehan, W. P., & Micheli, L. J. (2013). Pediatric Sports injuries: An age comparison of children versus adolescents. American Journal of Sports Medicine, 41(8), 1922.