ABSTRACT
This study was intended to examine the specific nature and an aerobic value of jumping jacks (Fig. 1) which has a greater movement in shoulders and is easy to perform in standing position without specific skill and equipment and in also a narrow place.<BR>Individual's self-selected (free) tempo in jumping jacks was determined for 92 subjects by administering it for 5 minutes.<BR>The optimal tempo was obtained from measuring energy expenditures on two subjects when they performed five minutes of jumping jacks at each tempo of 50, 60 and 70 times/min and also at one's free tempo. Exercise intensity of jumping jacks as a general endurance activity was determined from energy expenditures and % Vo<SUB>2</SUB>2max of 9 subjects who performed 5 minutes of jumping jacks at 60 times/min. Training effect of jumping jacks was examined on the basis of the changes in Vo<SUB>2</SUB>max and heart rate (jumping jacks at 60 times/min for 3 min) before and after one month of training on 7 subjects who participated 180 jumping jacks at free tempo a day, averagely 6.3 times a week. Subjects were all college male students aged between 18 and 22. Followings are the results obtained in this study.<BR>1) Individual's self-selected (free) tempo in jumping jacks was about 60 times/min.<BR>2) The optimal tempo in jumping jacks determined on the basis of energy expenditure was also about 60 times/min.<BR>3) Oxygen requirement and RMR at the optimal tempo (60 times/min) in jumping jacks were 40.9 ml/kg/min and 12.3, respectively. Percent Vo<SUB>2</SUB>max, Oxygen requirement and RMR in jumping jacks was smaller for persons who have greater Vo<SUB>2</SUB>max/body weight.<BR>4) One month of training by jumping jacks demonstrated significant increases in Vo<SUB>2</SUB>max and Vo<SUB>2</SUB>max/body weight, which were 2.59 to 2.751/min (p<0.01) and 43.5 to 46.1 ml/kg/min (p<0.05), respectively. Significant decreases in heart rate were also observed during and recovery after the exercise.<BR>5) From above results, jumping jacks could be used as an effective general endurance exercise, provided that some necessary modifications should be made according to each individual's fitness level.