In a study done at Tarleton State University in Texas, researchers reviewed 22 studies that investigated the effectiveness and safety of weight training in pre- and early-pubertal adolescent athletes. The studies focused on free-weight exercises as well as some machine-based strength training programs. In all 22 studies there was no link between experimental strength training programs and growth in height and weight of the subjects. Ten of the studies focused on injury rate, and only 3 injuries were reported, representing around 5% per 100 participant hours. The reason strength training in physically immature athletes is both safe and effective is due to the means by which greater strength is achieved. More physically mature athletes have the necessary level of hormones (testosterone, etc.) to illicit muscle hypertrophy (growth) from strength training. Larger muscles (which produce more force) do place a larger amount of stress on connective tissues (tendons and ligaments) and joints. But in a study out of Boston Children’s Hospital, researchers showed that strength gains in youth athletes are largely due to neuromuscular activation and muscular coordination. Essentially, young athletes muscles become “smarter,” instead of becoming bigger. This is also why young athletes tend to loose strength gains more quickly than older athletes who have actually changed the physical size of their muscle. There are some cases (most notably in female gymnasts) where intense physical training at a young age (sometimes coupled with poor nutrition) can cause a growth delay in young elite athletes. Have you ever seen a tall gymnast at the Olympics? But, researchers from the Department of pediatrics at the University of Wisconsin showed that delayed maturation had no effect on permanent adult height. Injuries in youth athletes are on the rise. However, increases in youth-athlete injuries are due to increased participation and the popularization of year-round participation in one sport. Overuse injuries from year-round participation in one sport is proven in research (see Sparta Point 1/14/09). Our youngest athletes we work with are freshmen in high school. The reason we do not work with younger athletes has nothing to do with physical limitations. Rather, we find that younger athletes rarely have the emotional maturity to commit to a program as intense as ours. Young athletes should focus on the reason we all started playing sports (FUN!). Once they are emotionally mature enough to commit to a strength training program, it is not only safe, but can help prevent overuse injuries by giving the athlete an “off-season” (like pro athletes take) where they don’t compete in their sport.One of the oldest and most prevalent myths about strength training is that it will permanently deform growth plates of younger athletes. Usually when people believe this myth they also think that strength training will permanently limit range of motion and flexibility in younger athletes. Luckily, both of these beliefs have been discounted by plenty of scientific research.
June 17, 2009
Weight training safe for growing athletes