Abstract

Twelve normal men performed 1-min incremental exercise tests to exhaustion in approximately 10 min on both treadmill and cycle ergometer. The maximal O2 uptake (VO2max) and anaerobic threshold (AT) were higher on the treadmill than the cycle; the AT was reached at about 50 of VO2max on both ergometers. Maximal CO2 output, heart rate, and O2 pulse were also slightly, but significantly higher on the treadmill. Maximal ventilation, gas exchange ratio, and ventilatory equivalents for O2 and CO2 for both forms of exercise were not significantly different. To determine the optimum exercise test for both treadmill and cycle, we exercised five of the subjects at various work rate increments on both ergometers. The treadmill increments were 0.8, 1.7, 2.5, and 4.2 /min at a constant speed of 3.4 mph, and 1.7 and 4.2 /min at 4.5 mph. Cycle increments were 15, 30, and 60 W/min. The VO2max was significantly higher on tests where the increment magnitude was large enough to induce test durations of 8-17 min, but the AT was independent of test duration. Thus, for evaluating cardiopulmonary function with incremental exercise testing by either treadmill or cycle, we suggest selecting a work rateincrementto bring the subject to the limit of his tolerance in about 10 min. Verf.-Referat