Abstract des Autors

The force acting on the right crank of a bicycle ergometer were measured in 18 male subjects (6 racing cyclists, 8 students of physical education, 4 long distance runners) during an incremental exercise test. Oxygen consumption (V02) was simultaneously determined by means of a breath-by-breath method. Differences in peak values of the typical force record might indicate a different force distribution during each cranking cycle. When compared to the reference group, the racing cyclists showed peak values that were significantly lower at all levels of work load. Oxygen consumption during the initial 20 min of the test was found to be significantly lower in the cyclist group (cyclists: 37.2 +/- 3.2 l, reference group: 41.1 +/- 3.9 l). These results suggest that a different force distribution during a crank revolution might lead to an improved gross efficiency in the cyclist group. The findings might be due to different fractions of ST-fibres in the exercising muscle.