John Saxton, senior research fellow in exercise physiology, replies: You are right to have concerns. This is not because of the purported health risks associated with weight training in children, but because your son may have unrealistic expectations of what can be achieved. Contrary to traditional beliefs, a properly designed and competently supervised weight training programme can be a safe way to increase strength, improve sports performance and decrease the risk of sports injuries in children. However, strength gains in children of this age are usually attributable to neural or motor learning adaptations rather than increased muscle bulk. This is because the hormonal changes that promote muscle growth (hypertrophy) do not usually occur until later in puberty. His frustration could lead to the adoption of an over-ambitious training programme, which could increase injury risk.
Your son's expectations must be addressed, but if he can learn safe and effective lifting techniques and develop the appropriate neuromuscular pathways for this type of activity, he may well experience greater success as he advances into maturity. The emphasis needs to be on good supervision and safety issues, such as correct technique and a controlled rate of progression. Maximum or near maximum efforts should be avoided. One to three sets of ten to 15 repetitions for the major muscle groups on non-consecutive days will enable progress to be made. Body resistance exercises, such as press-ups and sit-ups can also be encouraged. Any sign of joint pain should be treated seriously and the situation should be carefully monitored with a view to modifying the training programme.