Why? The Science of Athletics

HUMAN MECHANISM 103 both in the liver and in the muscles, which will be available when a sudden or sustained effort is required. Gluco~e is stored chiefly as glycogen, whereas if fat is used to provide glycogen there is a tendency to store it as fat rather than glycogen and so produce undesirable and useless weight. Acting as it does as a "protein sparet", glucose in the diet reduces the amount of nitrogen waste which has to be excreted by the kidney. It is well known that after severe exertion albumin is often present in the urine. It is desinible, therefore, that no extra strain should be thrown upon the kidneys. There is a point here about the habit of eating chocolate which is prevalent among field events athletes and distance men and also the need that is sometimes felt of slaking one's thirst. The drinking of water causes the stomach to empty rapidly. That emptying is less rapid when carbohydrates and proteins, such as starch and meat, are taken into the system and least rapid when fat has been absorbed. The eating of chocolate tides the distance man over h~s bad times and helps the field events exponent to retain his energy throughout a protracted competition, because, by the stomach emptying less - rapidly, the supply of nourishment reaching the blood is maintained at a more even rate than when the fat, contained in the chocolate, is absent from the athlete's system. We have seen, so far, what the muscles Lactic Acid feed upon and what is their fuel ; now we is Muscle- have to examine a substance which is Poison constantly at war with the athlete's friend, . glycogen. This substance is lactic acid. It Is the same acid that turns milk sour and causes the subsequent "clotting". Lactic acid, however, does not occur in our muscles through the agency of the lactic acid bacillus, as in the case of sour milk, but is liberated in -the muscle-substance proportionately to the violence of mus– cular contraction. When this happens fatigue ensues very rapidly.