Resistance training in youth and its effectiveness, possible effect on growth and safety considerations, has received considerable public and scientific attention in recent years. Although few early studies questioned the usefulness of resistance training in children, numerous recent studies have demonstrated its effectiveness in both children and adolescents. Nevertheless, the optimal intensity and volume of training for youths of different ages requires further study. The increase in strength following resistance training in youths, especially in prepubertal children, is believed to be due mainly to neural adaptations and only minimally, if at all, to muscle hypertrophy. Few studies have examined the long-term effect of resistance training on growth. The few which have, found that, contrary to the common misconception that resistance training may retard growth. Scientific evidence indicates that resistance training results in increased serum IGF-I and that there is no detrimental effect on linear growth. Finally, numerous studies have demonstrated that with appropriate supervision and precautions, resistance training can be safe and effective for children and adolescents.