Resistance Exercise for the Prevention and Treatment of Pediatric Dynapenia

Abstract

Temporal trends of youth muscular fitness (i.e., muscular strength, muscular power and local muscular endurance) indicate that contemporary children and adolescents are weaker and slower than previous generations. Consequently, this generation of millennials appear to be just as vulnerable as older adults to the inevitable consequences of muscle disuse and neuromuscular dysfunction. The modern-day construct of pediatric dynapenia describes an identifiable and treatable condition in youth characterized by low levels of muscular strength and power and consequent physical and psychosocial limitations not caused by neurologic or muscular disease. An interaction of modifiable physical and psychosocial factors can influence the development and progression of pediatric dynapenia. Without structured interventions that target strength deficits and build strength reserves in a supporting environment, the divergence in performance between weaker and stronger children may persist into adolescence because weaker youth may be unable to break through a so-called strength barrier. Regular participation in a well-designed youth resistance training program provides an opportunity for youth to enhance their health and fitness while acquiring the physical skills and behaviors that support an active lifestyle. New insights have highlighted the importance of initiating strength-building interventions early in life to optimize performance gains in other important components of physical fitness. Developmentally appropriate resistance training should be integrated into school-and community-based youth fitness programs and strength-building activities should take a more prominent position in public health physical activity recommendations for children and adolescents.

A 47-Year Comparison of Lower Body Muscular Power in Spanish Boys: A Short Report

“…This downward trend in muscular fitness in modern day youths has also been reported in children and adolescents from other countries [3]. It should be noted that, without regular opportunities to engage regularly in strength-building exercises, today's youths may be less likely to attain the adequate levels of muscular fitness that are needed for ongoing participation in MVPA [3,18]. Since low levels of muscular strength and power early in life are risk factors for pediatric dynapenia and associated health-related concerns [19], the SLJ has been suggested as a valid general index for assessing muscular fitness in youths [12].…”

“…It is possible that other factors, such as trends in quality and quantity of physical activity engagement, may contribute to the observed decline in muscular fitness in modern day youths. This downward trend in muscular fitness in modern day youths has also been reported in children and adolescents from other countries [ 3 ]. It should be noted that, without regular opportunities to engage regularly in strength-building exercises, today’s youths may be less likely to attain the adequate levels of muscular fitness that are needed for ongoing participation in MVPA [ 3 , 18 ].…”

“…Low levels of muscular fitness (i.e., muscular strength, muscular power and local muscular endurance) in children and adolescents are associated with poor motor competence, functional limitations and adverse health outcomes [ 1 , 2 ]. Recent findings indicate that measures of muscular strength and power in modern-day youths are lower than in previous generations [ 3 , 4 , 5 , 6 ]. Sandercock and Cohen reported a decline in muscular fitness (bent-arm hang, sit-ups and handgrip) using allometric equations in 10-year-old English children from 1998 to 2014, and noted this trend was independent of secular changes in body size [ 5 ].…”

“…Lower levels of muscular strength and power in modern day youths appear to be consequent to lifestyles characterized by reduced physical activity and increased sedentary behavior [ 3 , 5 , 8 ]. Importantly, muscular strength and fundamental movement skill proficiency are considered foundational for ongoing participation in physical activity across the lifespan [ 8 , 9 ].…”

The Promise of Youth Resistance Training

“…Despite this knowledge, global declines in measures of moderate to vigorous physical activity (MVPA) in modern day youth have coincided with temporal declines in measures of muscular fitness [11], [15], [25]. That is to say, this generation of physically inactive girls and boys is weaker than previous generations and, consequently, at greater risk for adverse health outcomes associated with physical inactivity and muscle disuse [10], [22]. Since a prerequisite level of muscular strength is needed to jump, kick, throw and run proficiently [20], concerted efforts are needed to "activate" this generation of boys and girls with developmentally appropriate interventions that target neuromuscular deficits before youth become resistant to exercise and sport programs.…”