STEP INCREMENT VERSUS CONSTANT LOAD TESTS FOR DETERMINATION OF MAXIMAL OXYGEN-UPTAKE

Ten male subjects performed 5 maximal treadmill running tests at 7 mph. Tests included 2 (test-retest) progressive, step increment (2 1/2% grade elevation), discontinuous tests (DCT); a progressive, step increment, continuous test (CT) and 2 constant load tests (CL and CL + 2 Y2%). A DCT test was performed 1st for establishment of peak elevation levels as constant load tests were performed at the peak elevation level attained (CL) and at a level 2 1/2% higher (CL + 2 1/2%). The 2nd DCT test and the remaining 3 tests were administered randomly. Peak performance capability (operationally defined as duration at highest grade elevation) was markedly reduced during progressive tests as compared with constant load tests. There was a similar reduction in peak performance capability during the CT test as compared with the DCT test. Maximal O2 uptake (.ovrhdot.VO2 max) was quite similar among the various tests. .ovrhdot.VO2 max attained during progressive, step increment, tests was probably unaffected by cumulative submaximal work. Discontinuous and continuous progressive tests provided similar .ovrhdot.VO2 max results.