Weightlifting is a fundamental part of any exercise program. Whether you are attempting to build muscle, lose weight or maintain your desired body size and shape, adding weightlifting to your daily workout can help you achieve your goals. While these benefits may hold true for a fully grown adult, you may be concerned about the effects of weightlifting on the growing body if you are a young athlete or health-conscious parent.
Effects on Growth Plates
The epiphyseal plates, otherwise known as growth plates, are responsible for bone growth in children and adolescents. Located at the ends of bones, these cartilage plates divide and regenerate throughout a child's development, helping form new bone in the process. The process of regeneration eventually stops when you reach your full height, with the cartilage plates mineralizing and forming the ends of your mature bones. Worries about damage to the growth plates have fueled belief in a link between weightlifting and stunted growth, Due to the impact of weightlifting on your bones and joints, according to to a 2009 study by Katherine Dahab and Teri McCambridge of Johns Hopkins University.
Hormones and Bone Growth
In a 2010 study, Andrew Fry of the University of Kansas and Corey Lohnes of Washington University linked weight-training exercise to an increase in testosterone production. Involved in bone growth, muscle development and the closure of the growth plates, testosterone may have contradictory effects on growth. In a 2009 review of the literature on hormones and bone growth, Bart Clarke and Sundeep Khosla of the Mayo Clinic present evidence for testosterone's effect on both bone growth and the closure of the growth plates. Though their review shows that testosterone may not significantly affect the closure of the growth plates, these findings suggest that weightlifting may stunt your growth.
Dismissing the Myths
According to Dr. Avery Faigenbaum of the University of Massachusetts, concerns about weight lifting stunting the growth of children and adolescents are outdated and misleading. Instead, he suggests that eating a healthy diet and exercising regularly allow you to achieve your maximal height, with inactive, unhealthy eaters more likely to have stunted growth. Betsy Keller of Ithaca College suggests that this myth exists because some researchers focus only on specific groups of athletes. In a 2008 review of the literature, she suggests that evidence for weightlifting's negative impact on growth arises solely from sports that are well-suited for shorter people, such as women's gymnastics and competitive dancing.
In contrast with suggestions of stunted growth among young weightlifters, Betsy Keller points out that weightlifting may be more effective than other forms of exercise in promoting bone growth and density among adolescents. Joshua Yarrow of the Veterans Administration Medical Center supports this evidence in a 2008 study. These researchers found that testosterone injections increase both bone length and density, suggesting that weightlifting's impact on testosterone may be beneficial.
With both direct and indirect evidence suggesting that weightlifting may increase bone length and density, it seems as though this myth is untrue. Rather than stunt your growth, weightlifting when you are young may allow you to grow taller than you would without such exercise.