For the purpose of this review, a “novice” refers to an individual who has no or limited resistance training experience (≤2 to 3 months) or an individual who has not trained for several months. “Intermediate” refers to an individual who has approximately 3-12 months of consistent resistance training experience. “Advanced” refers to those individuals with at least 12 months of resistance training experience who also attained significant improvements in muscular strength and power.
Although there is not one model of periodization, the general concept is to prioritize training goals and then develop a long-term plan that changes throughout the year. By periodically varying the training intensity, training volume, rest interval length, and exercise choice, the risk of overtraining may be minimized and potential for maintaining training-induced gains could be maximized (99). It is worth noting that periodized training programs should include periods of active rest (e.g., 1-3 weeks recovery between sport seasons) to allow for physical and psychological recovery from the training sessions. This is particularly important for youth who represent different sports teams, specialize in 1 sport year-round, or participate in extracurricular conditioning activities at private training centers. In addition, to promote long-term gains in strength and performance in children and adolescents, training programs should include educational sessions on lifestyle factors and behaviors that are conductive to high performance (129). Of note, the importance of proper nutrition (52), sufficient hydration (44), and adequate sleep (165) should not be overlooked. A detailed review of periodization and lifestyle factors that may influence athletic performance are beyond the scope of this review, but they are available elsewhere (129,136,138).
Despite outdated concerns regarding the safety or effectiveness of youth resistance training, scientific evidence and clinical impressions indicate that youth resistance training has the potential to offer observable health and fitness value to children and adolescents, provided that appropriate training guidelines are followed and qualified instruction is available. In addition to performance-related benefits, the effects of resistance training on selected health-related measures including bone health, body composition, and sports injury reduction should be recognized by teachers, coaches, parents, and health care providers. These health benefits can be safely obtained by most children and adolescents when prescribed age-appropriate resistance training guidelines.
We now have the information to support the consideration of incorporating resistance training into a health-oriented approach to lifelong physical activity. Important future research goals should be to elucidate the mechanisms responsible for the health-related benefits associated with youth resistance exercise, to establish the combination of program variables that may optimize long-term training adaptations and exercise adherence in children and adolescents, and to explore the potential benefits of resistance training on youth with various medical conditions including obesity, diabetes, cancer, severe burns, and physical limitations, and intellectual disabilities.
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