Abstract

12 young boys as an experimental group and 7 as a control group, aged 5-6 years, participated in a study to clarify whether circulorespiratory trainability exists in young children. The subjects in the experimental group performed a 915 m endurance run every day except Sundays for six months. During the run, heart rates (HR) equivalent to 3-4 mmol/l of blood lactate concentration (LA) were maintained for at least 3-4 min/m. The control group was given no special training. Before and after the training period, both groups were subjected to stepwise increased running on a flat treadmill till subjective exhaustion to determine circulorespiratory variables such as heart rate (HR), oxygen uptake (VO2) and blood lactate concentration (LA) at all steps. The following findings were obtained: 1) After the 6-month endurance run training, VO2max/TBW was significantly increased from 47.5 to 50.4 ml/kg/min and also the peak LA was significantly increased from 5.41 to 6.36 mmol/l in the experimental group. No significant increases were observed in the control group. 2) Running velocity in the final stages (Vmax) was significantly improved from 190.0 to 205.0 m/min in the experimental group. Such effects were due partly to the improvement of circulorespiratory function and partly to improved efficiency of running motion. 3) Submaximal V, HR, and VO2/TBW equivalent to 3 and 4 mmol/l and their values relative to the maximum values showed no significant differences before and after the training period in both groups. Verf.-Referat