Abstract des Autors

Thirteen male subjects performed a running test on the treadmill consisting of four standard exercise intensities (65, 75, 85, 95 VO2max) presented in ascending, descending or random order. At the end of each exercise intensity, O2 concumption, heart rate (fc), venous blood lactate concentration ((la)b) and perceived exertion were assessed. This last variable was determined according to the Borg nonlinear CR-20 scale. The same variables were also determined during exercise at a standard intensity (65 or 95 VO2max) performed before and after a Finnish sauna bath. Ratings of perceived exertion showed a good test-retest reliability (r = 0.77); they were the same when the exercise intensity was expressed in relative (VO2max) or absolute (speed) terms, and were independent of the order of presentation of the exercise. The latter had no effect on fc either but it did, however, influence (la)b, which was significantly higher in the descending, as compared to the ascending or random modes of presentation. The sauna bath increased fc at a given exercise intensity, but left perceived exertion and (la)b unchanged. It was concluded that at least under the present experimental conditions, fc and venous (la)b do not play a major role as determinants of perceived exertion.