Effects of Maturity Level, Sex and Work Intensity on the Response of Selected Measures of Ventilatory, Metabolic and Circulatory Function to Prolonged Physical Activity in Children

224 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1983.The responses of selected measures of ventilatory, metabolic and circulatory function to prolonged physical activity of mild and moderate intensity in prepubertal and adolescent children were investigated. Three questions were considered: (1) Do prepubertal and adolescent children respond, physiologically, in a similar manner to prolonged work?; (2) Is there a sex related difference in those responses? and (3) Do these response relationships vary with work intensity? Four groups of subjects (10 prepubertal boys, 10 prepubertal girls, 10 adolescent boys and 10 adolescent girls) underwent treadmill testing for aerobic power determination. Each subject then participated in a prolonged exercise protocol at each of two levels of work intensity (50% and 75% VO(,2) max). Adolescent subjects displayed physiological responses to prolonged work which were of greater magnitude than those of the prepubertal group at both work intensities. This was attributed to the greater body mass of the older subjects rather than to functional differences. Higher measures of aerobic power (VO(,2) max) and greater body mass in adolescent males as compared to females accounted for the significant effort of sex on the response to prolonged exercise. The responses of the male subjects were greater in magnitude than those of the females at both work intensities. It was concluded that body size and fitness level (aerobic power) were responsible for the differences in responses to prolonged effort seen between males and females of the adolescent group and that the work of higher intensity increased those differences. Furthermore, prepubertal and adolescent subjects adjusted similarly to prolonged exercise and tolerated both levels of work intensity equally well.U of I OnlyRestricted to the U of I community idenfinitely during batch ingest of legacy ETD