Fractional utilization of the aerobic capacity during distance running

Field and laboratory studies were made on 16 trained distance runners to determine the relationship between selected metabolic measurements and distance running performance. Measurements were made for oxygen consumption, heart rate, and blood lactate accumulation during submaximal and maximal treadmill running. Several days after the laboratory test all of the runners competed in a 10-mile road race. The correlation between maxV̇o2 (ml/kg x min) and performance in the 10-mile race (min) was −0.91 At a selected speed (268 m/min) the % maxV̇o2 and % max HR were found to be highly related to distance running performance (r = −0.94 and 0.98, respectively). At all running speeds above 70% maxV̇o2 the faster runners were found to accumulate less blood lactate than the slower runners at similar speeds and relative percentages of their aerobic capacities. The findings suggest that successful distance running is dependent on the economical utilization of a highly developed aerobic capacity and the ability to employ a large fraction of that capacity with minimal accumulation of lactic acid.