Endurance capacity for continuous effort in terms of aerobic and anaerobic fraction of oxygen supply.

ABSTRACT

Studies have been conducted on 13 young healthy adults of average fitness on endurance work of varying durations lasting for 2-31 minutes using bicycle ergometer. Aerobic-anaerobic fractions of oxygen supply during each effort was determined. The data from Astrand and Rodahl on aerobic O2--supply and duration in maximal efforts from 1-120 minutes on a highly trained subject have also been considered. The plot of log endurance time against log (aerobic/anaerobic ratio) exhibits a slight departure from linearity, indicating independent contributions from aerobic and anaerobic fractions of oxygen supply. An equation was derived of the form T - Au1k1u2--k2 where u1 end u2 are the aerobic and anaerobic fractions respectively which has been found to yield highly significant correlation coefficient between log-estimated and log-observed endurance time (0.9996 for Astrand and Rodahl's data on a single subject and 0.9640 for the present data on 13 subjects). This index is, therefore, quite suitable for the assessment of endurance capacity in terms of a single physiological parameter, and is likely to be superior to indices in current use.