Why? The Science of Athletics

HUMAN MECHANISM has been said already about the reaction of the medulla to th~ presence of carbon dioxide in the blood supplies the explanation, for once fatigue is incurred, the stimu– lation of the respiratory and circulatory systems, through the inspiration of the medulla, will be quite sufficient for them to set oxygen circulating faster in the blood until the debt is discharged. The value of training, in this connection, lies in the fact that by training a man can build up a large oxygen income and can also obtain a larger oxygen credit. The credit is of the greater interest to the sprinter, the income to the distance runner. The income depends upon the amount of oxygen per minute a man can take into his lungs, and this, again, depends upon the man's own vital lung-capacity and the rate at which his heart can pump his blood round his body. The maximum oxygen income of a well-trained athlete is believed to be somewhere in the region of 4 litres per minute. The oxygen-debt, again, varies with the type of the individual desiring to obtain credit. A well-trained and naturally powerful athlete may incur an oxygen debt of as much as I 5 or 20 litres of oxygen to assist his recovery, after a short period of exertion, by the removal of the lactic acid which· has accumulated in his blood during the making of that effort. It is possible to study athletics quantitatively, to measure a man's maximum oxygen income and debt and in fact, to assess the efficiency with which he runs. With such data available it is then possible to deduce, moderately accurately, from considerations of energy and oxygen consumption, the .speed at which he will run a given distance. If such an experiment is carried out with a trained and experienced athlete, who knows pretty well the extent of his own capabilities, a table can be drawn up to show the approximation of the scientist's deductions and the forecasts, which have been based upon the athlete's knowledge of his own capacity, with his performances