Resistance training is essential for optimal growth and development in the youth population and has shown to be safe and effective (Faigenbaum et al., 2009). This form of training can provide significant benefits within this group, which may have a substantial impact on future participation in physical activity and decrease risk of health complications. Furthermore, resistance training has been shown to have a positive impact on strength levels, motor performance and overall health in children as young as five years old (Faigenbaum et al., 2009). Specifically, strength, motor and health improvements in the youth population as a result of training are more related to, and influenced by, neural and neuromuscular adaptations in comparison to muscular adaptations (e.g., hypertrophic factors), which need to be taken into consideration by health and exercise professionals (Granacher et al., 2018; Faigenbaum et al., 2009). A youth resistance-training program, although shown to be beneficial, must be properly programmed and supervised by a qualified exercise professional to ensure the safety and optimal development of the participants. Therefore, evidence-based recommendations for youth resistance exercise should be taken into consideration.
Youth resistance-training adaptations connected to enhancements in strength levels and motor performance result from neural and neuromuscular mechanisms, rather than hypertrophy (muscular) mechanisms (Granacher et al., 2018; Faigenbaum et al., 2009). Specifically, training-induced neural and neuromuscular adaptations include the following: increases in motor-unit synchronization, recruitment and rate coding (Granacher et al., 2018; Faigenbaum et al., 2009). Increased motor-unit synchronization results in the improvement of motor-unit recruitment in unison, while enhancements in motor-unit recruitment result in more motor units and higher threshold motor units being recruited (as based on the size principle). In addition, improvements in rate coding result in increases in firing frequency or discharge rate of motor units (Folland and Williams, 2007). All of these factors lead to improvements in force and power production and motor performance in the youth population. In addition, connective tissue and bone strength and durability are enhanced through resistance training in this group. Training-induced muscular adaptations occur secondary, primarily observed as increases in fiber-twitch contraction speed (Faigenbaum et al., 2009). However, hypertrophic mechanisms have a minimal influence on strength gain in the youth population, as vital hormones (e.g., testosterone) that stimulate increases in muscle size and gain do not reach adequate levels until an individual starts to mature (i.e., during and after puberty) (Faigenbaum et al., 2009).
Training the youth population is unique and some health and exercise professionals may not be as experienced in serving this population in comparison to the adult population. Proper understanding and application of resistance-training principles, and the understanding of the uniqueness and characteristics of the youth population need to be utilized and taken into consideration, respectively (Dahab and McCambridge, 2009; Faigenbaum et al., 2009). Neuromuscular resistance training, which encompasses both fundamental and dynamic, advanced movements, needs to be included in a youth resistance-training program (Granacher et al., 2018; Faigenbaum et al., 2009). This type of training focuses on learning and properly performing fundamental movements (e.g., walk, run, accelerate, decelerate, jump, land, push, pull, hinge, squat, rotation and anti-rotation), which provide a movement foundation that could potentially lead to more dynamic, advanced movements. In addition, static and dynamic balance should be emphasized. These factors are related to neural and neuromuscular mechanisms.
Training to induce hypertrophy should not be as emphasized in youth, as the mechanisms underlying this training adaptation have a minimal impact on strength gains.
The most significant variable in creating a successful youth resistance-training program is making sure participants are having fun, while also providing support and encouragement. Specifically, having more fun within a program that is properly supervised and programmed will lead to long-term consistency and adherence, which will result in greater outcomes. Therefore, while application of training principles is important, the appreciation of the characteristics of the youth population is of the greatest importance when creating a successful resistance-training program.
References
Dahab, K.S. and McCambridge, T.M. (2009). Strength training in children and adolescents: Raising the bar for young athletes? Sports Health, 1, 3, 223-226.
Faigenbaum, A.D. et al. (2009). Youth resistance training: Updated position statement paper from the National Strength and Conditioning Association. The Journal of Strength and Conditioning Research, 23, Supplement 5, S60-S79.
Folland, J.P. and Williams, A.G. (2007). The adaptations to strength training: Morphological and neurological contributions to increased strength. Sports Medicine, 37, 2, 145-168.
Granacher, U. et al. (2018). Editorial: Neuromuscular training and adaptations in youth athletes. Frontiers in Physiology, 9, 6-10.
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