Energy cost of graded work loads & mechanical efficiency of sportsmen

This study was undertaken to determine oxygen consumption at rest and constant graded work loads while exercising on a bicycle ergometer and to compute mechanical efficiency of sportsmen. Thirteen healthy, active, well trained young sportsmen from sports hostel, Sports Authority of India, Hyderabad, were selected and were requested to pedal the bicycle ergometer at 50 watts and 100 watts (300 and 600 kpm) work loads for 18-20 min. The energy cost of the activity at the respective work loads was measured by means of indirect, open circuit respiratory exchange method. The workouts resulted in the oxygen consumption of about 920.4 +/- 77.5 ml and 1475.2 +/- 101.7 ml at 300 and 600 kpm respectively. The gross or absolute mechanical efficiency (AME) were calculated at these work loads. The delta mechanical efficiency (DME) was also computed for the work increment from 300 to 600 kpm by using the amount of oxygen consumed at these work loads. The AME was about 23-24 per cent in both the loads while the DME was found to be 26 per cent. The relationship between anthropometry, resting metabolic rate (RMR), AME and DME was assessed. It was observed that both AME and DME values of these subjects were in the normal range of Swedish and Canadian active young men. These parameters can be used as indicators for assessing sports persons efficiency both in the active and lean periods.