Abstract

Pulse rate and oxygen consumption were measured for 19 boys (aged 12-13) assigned to either Distance, Interval, or No-Training regimes, during a 5 min. run at 6 m.p.h., zero grade on a motor driven treadmill prior to a 12 week conditioning period, following conditioning, and after four months of deconditioning. Oxygen consumption was assessed by opencircuitry and heart rate monitored by direct electrocardiography. Both conditioning groups significantly improved cardiovascular fitness (Distance group: 175-152 beats/min. and Interval group: 175-159 beats/min.), but no differences were noted between them. They differed significantly from the Control group which showed no change (172-173 beats/min. No significant differences occurred between any of the groups for V02 variables, but within group analysis statistically favored the Distance group. Post-conditioning and -deconditioning comparisons indicated that deconditioning had a deleterious effect on cardiorespiratory function. Cardiorespiratory fitnes improved to the extent that competitive running events of 2-6 miles are suggested for this age group, but as the data indicated, only after sufficient training. Task similarity of training and standard test and running volume apparently afforded a slightly greater improvement of cardiorespiratory fitness in the Distance group. Marked deterioration of fitness during deconditioning was attributed to complete absence of a training stimulus.Verf.-Referat