Can Weight Lifting Stunt Growth? Experts Explain
Sports & Activity
Here's what coaches say about the risks of weight lifting for tweens and teens.
There's ample evidence that participating in sports when people are young can potentially kick off a lifetime of consistent fitness habits, heighten self-confidence, and even impart a sense of empathy and resilience. And while engaging in athletics from an early age offers a host of benefits, it’s important to keep overall health in mind. Enter the longstanding controversy: Does lifting weights stunt growth in tweens and teens?
The short answer: no. But there are some caveats to keep in mind for teens looking to begin weight training, according to Carol Mack, D.P.T., C.S.C.S., strength coach and doctor of physical therapy.
"There's no evidence that weight lifting stunts growth," she said. "In fact, resistance training can help build coordination and strength in young athletes, and there's a strong push right now for young female athletes to lift weights in the hope that it may offer more injury prevention. That being said, there should be a focus on building proper form for this population before adding weight or resistance to their movements."
What the Research Says
The National Strength and Conditioning Association released a position statement on the issue of young people and strength training in 2009 and hasn't updated that guidance since. That statement notes: "[R]esearch increasingly indicates that resistance training can offer unique benefits for children and adolescents when appropriately prescribed and supervised. The qualified acceptance of youth resistance training by medical, fitness, and sport organizations is becoming universal."
The statement concluded by calling concerns about youth resistance training outdated, and said that there's now enough information to support the practice, as long as training follows age-appropriate guidelines.
Research published since those guidelines were first issued support the safety of strength training for young people. For example, a 2020 clinical report from the American Academy of Pediatrics stated that properly designed resistance training programs have no apparent negative effect on linear growth, growth plate health, or the cardiovascular system of children and adolescents.
A research review published in a 2016 issue of Frontiers in Physiology found that resistance training done by young athletes provides benefits for long-term health and athletic performance, since it provides neuromuscular adaptation.
Another research review, in a 2009 issue of Sports Health, noted that injuries related to strength training for young participants were primarily caused by misuse of equipment, inappropriate weight, improper technique, or lack of qualified adult supervision, rather than by lifting itself.
As Mack noted, more female athletes are also being encouraged to start resistance training, and for good reason. Most notably, ACL tears are more common in female athletes because the structure of their knee joints is different than it is for male athletes, putting them at higher risk. Having low muscle mass in the legs can increase that risk, according to Johns Hopkins Medicine, which means building strength can have a protective effect.
How To Prevent Injury in Teens Who Weight Lift
While the research-based answer to "Can weight lifting stunt growth?" is a resounding no, that doesn't mean the activity is free from risk. Like any exercise, it's possible for participants to become injured, especially if incorrectly performing the move.
That's why it’s crucial to provide effective supervision and guidance on proper form, Mack said, and that means individualized training programs. While that's not always possible — for example, an entire football or swim team may all be in the school weight room at once — she believes that doing as much one-on-one training time at the start of a weight lifting endeavor can pay off in the long run.
"At the high school where I provide strength training, I often find that if we spend a lot of individualized time with our freshmen, they are proficient with most exercises and weights to use by their junior and senior years," she said.
Another tip: Make sure a training program follows that "age-appropriate" designation suggested by the NSCA, according to Rocky Snyder, C.S.C.S.
"Some online programs are designed for youth by simply taking adult programs and repurposing them, but this is a problem," he said. "An adolescent body is different from a mature adult. Motor control, flexibility, existing strength levels, hormonal changes, mental and physical maturity levels are just some key elements to consider when developing a comprehensive program for youth athletes."
He recommended that athletes, parents, coaches, and anyone in the athlete’s support system look at the NCSA infographic on youth resistance training, which outlines strategies to get started and stay safe. These range from beginning with relatively light loads and always focusing on correct technique to gradually increasing resistance by 5 to 10% as strength improves, and optimizing performance and recovery with healthy nutrition, proper hydration, and adequate sleep.
"What I've seen is that strength training is wonderful for their confidence," Mack said. "That's true in the short-term, but also in future years of college and adulthood."
Words by Elizabeth Millard