A common question we receive from parents is "when can my child start weight training". This is a difficult question to give a standard answer on because so many variables are at play including the maturity of the athlete (skeletal, neuromuscular, emotional, and mental), the demands of their sport, and their training experience. Our main concern would be the technique and form the athlete can demonstrate without resistance. Adding a bar or weight plate onto poor technique, form, or coordination is a recipe for injury. As in any exercise program, if resistance training is applied properly in the right athlete positive adaptions will take place. In children, the strength gains noted are more due to improvements in neural communications to other nerves or muscles and not due to changes in muscle size (Faigenbaum et al. 2001 and 2009). This improved coordination and communication between the nervous and musculoskeletal systems highlights the importance of technique over the amount of weight the athlete can lift.
A recent study examined the impact of a strength training program of 18 healthy, pre pubescent boys (Tanner Stage I) ranging from 10-12 years old (Cunha et al. Research Quarterly for Exercise and Sport. 2015). The boys were divided into two groups of 9 and randomized to either a resistance training group or a control group. The resistance training group lifted weights 3 x per week for 12 weeks under close supervision. The coach to athlete ratio of 1:4 should be emphasized. Each athlete went through a warm up, stretching, and weight training program emphasizing major muscle groups for 60 minutes. Athletes were re tested following this 12 week intervention program. The resistance training group showed significant improvements in strength measurements and lean body mass by DEXA scanning. The resistance training group also prevented gains in fat mass compared to the control group.
In short, choosing a resistance training program for young athletes should be a case by case decision. A Physical Therapist must evaluate the athlete for variables which would make a program of resistance training appropriate for each athlete. In our experience, most individuals aged 10-12 should focus on skill and motor development as they move through middle school. These positive changes in movement and coordination will serve them well as they begin a resistance training program.
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