Is Strength Training Safe for Kids? The Evidence

The short answer, from every American body that has published on it, is yes — with the same condition attached every time: properly designed and properly supervised. The interesting part is how strong the evidence behind that answer turns out to be.

The growth plate question

This is the fear the topic runs on: that loading a growing skeleton damages the growth cartilage and costs a child height. The NSCA position statement addresses it directly:

“To date, injury to the growth cartilage has not been reported in any prospective youth resistance training research study. Furthermore, there is no evidence to suggest that resistance training will negatively impact growth and maturation during childhood and adolescence.”

The statement does not pretend the tissue is invulnerable. Growth cartilage injuries have been reported in preadolescents and adolescents in the wider literature — but, in its words, “most of these injuries were due to improper lifting techniques, maximal lifts, or lack of qualified adult supervision.” It also notes that growth cartilage may actually be more resistant to shearing forces in younger children than in adolescents.

What the injury numbers look like next to other sports

In a prospective study that tracked sports-related injuries in school-aged youth over one year, resistance training accounted for 0.7% of 1,576 injuries. Football accounted for about 19%, basketball 15% and soccer 2%. Ranked by injury-to-participant ratio in school team sports, the top of the list was football (28%), wrestling (16.4%) and gymnastics (13%).

Inside the training literature itself, the tally is smaller still. Across published prospective studies, the statement counts three reported resistance-training injuries in children: a shoulder strain that resolved within a week of rest, a shoulder strain that cost one training session, and nonspecific anterior thigh pain that resolved after five minutes of rest.

The AAP frames the same comparison from the clinic side: “proper strength training has been shown to allow an increase in strength with fewer injuries than occur during recess at school.”

Where the real risk sits

Not in the barbell. The AAP page on weight training injuries is explicit that most serious injuries — including deaths — came from unsupervised home gym equipment, with children playing around or challenging one another, and from attempts at a maximal lift before a child is physically developed or properly instructed. Reported injuries in those circumstances have included herniated disks, muscle strains and tears, fractures, growth plate injuries and cartilage damage.

Read alongside the training studies, that is a consistent picture: the injuries cluster where supervision and technique are absent, and the same activity performed under coaching produces almost none.

What the federal guidelines say

The Physical Activity Guidelines for Americans put it in two sentences that are worth keeping together, because quoting either one alone distorts them: “Children do not usually do or need formal muscle-strengthening programs, such as lifting weights. However, these programs are safe for children if they are properly prescribed and supervised.”

So a child who climbs, jumps and plays tug-of-war is already meeting the muscle-strengthening component. A structured program is an option, not a requirement — and it is a safe one when run properly.

For what “properly” means in sets and reps, see youth strength training guidelines; for when a child is ready at all, what age can kids start lifting weights; and for how the program evolves, strength training for teens. The broader activity target is in physical activity guidelines for children.

This content is informational and does not replace advice from a pediatrician or a qualified strength and conditioning professional.