Often parents are concerned by stunting growth that accompanies early weight training for kids. Research shows just the opposite!
A study compared the effects of 7 weeks of bodyweight, mobility, and resistance training programs on strength, power, and sprint times. Thirty-nine male adolescents (aged 14–15 years) were randomly assigned to 1 of 2 groups: bodyweight and mobility training (BMT) or combined bodyweight, mobility, and free-weights training (CBT).
Results show BMT and CBT can be beneficial for the development of physical performance capacities in untrained male adolescents. Increased training frequency with the addition of free weights provided the greatest training effects.
Earlier the better; training under supervision of a qualified expert is recommended.