ABSTRACT
This chapter briefly reviews several studies dating to the late nineteenth and early twentieth century through the 1960s, and then addresses issues related to evaluating potential effects of physical activity on growth and maturation of youth. It considers the influence of physical activity on indicators of growth, biological maturation, and body composition in the general population of youth and then in youth athletes. A frequently cited study highlighting the influence of activity on growth in fat-free mass (FFM) has relevance for youth athletes. Correlation and regression analyses in youth of mixed weight status generally indicate low and at best moderate relationships between habitual activity and indicators of adiposity. Evidence from a variety of cross-sectional and longitudinal comparisons of active and less active youth indicate a beneficial effect of regular activity on bone mineral content (BMC) and/or bone mineral density (BMD). Physical activity and training may influence body weight and composition.
