The maximum oxygen intake. An international reference standard of cardiorespiratory fitness

Abstract

Lack of cardiorespiratory fitness may well contribute to the increasing prevalence of degenerative cardiovascular disease throughout the world. As a first step towards co-ordinated and internationally comparable investigation of this problem, methods of measuring the reference standard of cardiorespiratory fitness-the maximum oxygen intake, (Vo(2))(max)-were compared by an international working party that met in Toronto in the summer of 1967.Repeated testing of 24 subjects showed that the (Vo(2))(max) was greatest on the treadmill, 3.4% smaller in a stepping test, and 6.6% smaller during use of a bicycle ergometer. There were also parallel differences in cardiac stroke volume. Uphill treadmill running was recommended for the laboratory measurement of (Vo(2))(max), and stepping or bicycle exercise for field studies. A discontinuous series of maximum tests caused some improvement in the fitness of subjects, and a "continuous" test (with small increases in load at 2-min intervals) was preferred.