VO2 max during progressive and constant bicycle exercise in sedentary men and women

VO2 max, as obtained by five cycloergometric test protocols, was studied in 14 normal sedentary subjects: seven women (from 21--35 years) and seven men (from 21--48 years) who carried out four (n = 14) or five (n = 8) of the following exercise programmes: triangular tests, which consist of increasing the load (1) 20 W/min; (2) 30 W/3 min, rectangular tests at constant load; (3) the highest load which the subject could maintain for about 10 min (MSP + 20 W); (4) maximal supported power (MSP) during 20 min; (5) trapezoidal test, consisting of a rectangular exercise of 40 W (10 min), followed test no. 2. Exercises were performed on a cycle ergometer, while VE, VO2, VCO2, f and fH were continuously measured with an open circuit system. In women, the VO2 max (mean +/- SEM) was lower (36.5 +/- 2.1 ml . kg-1 . min-1) than in men (48.7 +/- 3.6 ml . kg-1 . min-1). The highest ventilation rate observed during exercise for the whole group (VE = 101 + 13 l . min-1) was always lower than the maximal voluntary ventilation (MVV = 144 +/- 131 . min-1, p less than 0.001). VO2 max strongly correlated with lean body weight, VC, FEV1, and MVV. In spite of the significant differences between the maximal load level sustained with the first three tests, the VO2 max values were not significantly different. Moreover, there exists an excellent correlation between them. It appears that neither the absolute load sustained in the tests, nor the duration nor intensity of the submaximal load which preceded the maximal level (tests 1, 2, and 5), influence the value of VO2 max.