Progressive work capacity tests were designed attempting to provide comparable energy demands on the treadmill, bicycle and adjustable stepping device. The respective initial work stresses 3.0 mph — 2.5% grade, 60 Watts — 50 revs/minute and 30 steps/min — 4.5 cm step height, were estimated to demand V̇o2 responses 4 x rest (4 Mets). Each work increment, applied every 2 minutes, was 2.5% for treadmill, 25 Watts for bicycle and 4.5 cm for the step device and was estimated to increase V̇o2 by 1 Met. To test the accuracy of the V̇o2 estimates and possible interchangeability of tests, 10 healthy male adults performed the three tests randomly and V̇o2 was measured during the 2nd and final minute at each load. In addition, all subjects performed a series of 5-minute tests for comparison of each of the 5 minute V̇o2 values (the fifth minute value being the criterion for “steady state”) with those measured at identical loads in the progressive test.
There were no differences (P > .05) between V̇o2 values measured in the 5th minute of the 5-minute tests and those at identical loads in the progressive tests. In most instances V̇o2 demands were met by the 2nd minute in the 5-minute tests.
The progressive test V̇o2 measured responses for the treadmill, bicycle and step device were found to be unique to the instrument loads used. However, load corrections were calculated that would elicit a single-line metabolic response for the loadings on the three tests. The heart rate responses were found to be similar for the three tests while the ventilation responses appeared unique to the test instrument used.