The Effect of Amount of Physical Activity on Cardio Respiratory Fitness and Body Composition

Abstract

The goal of this study was to assess the effects of amount of ergometer cycle training on Vo 2 max and body composition in overweight women. Forty-one sedentary premenopausal women, age 25 to 45 years, were randomly assigned in three groups. Cycle ergometer training consisted of one day per week for group A, two days per week for group B and three days per week for group C. Participants trained for 60 min in any session with moderate intensity (50-60% Vo 2 max) for 12 weeks. Participants were counseled not to change their diet during the study period. There were no significant differences among variables in three groups at baseline. Means (±SD) of weight, body fat, WHR, BMI and Vo 2 max in groups were 67.43±9.54kg, 31.56±4.6 percent, 0.82±0.05, 25.54±4.16 kg/m 2 and 31.72±7.2 ml.kg -1 min -1 respectively. After 12 weeks, ANOVA test indicated there were significant differences among mean body composition among the three groups. Use of Tukey post-hoc tests showed that difference in theses groups is because of group C. Paired 't' test showed that there was significant difference between mean body composition (p<0.01) in group C. Vo 2 max in group B and C improved 12% and 21% (p<0.01) respectively with ergometer training. But in group A it was not changed significantly. These findings indicate that the three days in week with 60 min of moderate-intensity, cycle ergometer training is sufficient to improve body composition and Vo 2 max in over weight women. With two days training i.e. 120 min in a week only, Vo 2 max improved. The results indicate that two days regular training improves Vo 2 max in overweight women without change in body composition. With less of amount of physical activity neither body composition nor Vo 2 max improve significantly. These findings strongly suggest that, in the absence of changes in diet, a higher amount of activity is necessary for improving body composition and Vo 2 max.