The energy used in "sprint" running

Abstract

The large amount of energy used in muscular exercise of extreme severity has been demonstrated by recent work on the oxygen requirement of such exercise. Sargent (1, p. 16), for example, has found an oxygen requirement of nearly 30 litres per minute in a subject running 120 yards at an average speed of 9.23 yards per second, which is about eight times his maximum oxygen intake. Our previous paper will have explained how this great expenditure of energy occurs; it is not used mainly in overcoming any resistance external to the body, but rather the “viscosity” of the muscles of the subject himself. The mechanical work done can be calculated by the methods outlined in that paper, and it is of interest to compare it with the oxygen used in recovering from the effort made, which is a measure of the total energy expended. The Mechanical Efficiency of the Body in Running .—For the purpose of these experiments the subject is first caused to rest for 45 minutes, and a measure­ ment is made of his resting oxygen consumption. Then, without any other exercise, he is required to run 60, 100, or 150 yards at top speed, to pull up as rapidly as possible, and to collect his expired air for 30, 40 or 50 minutes, depending on the time needed for complete recovery.