III. EXPERIMENTS WITH UNIVERSITY STUDENTS, TRAINED IN ATHLETICS.
Men in training for athletic events deem it necessary to consume large amounts of proteid food. Great muscular activity, it is true, calls for the expenditure of corresponding amounts of energy, but it is by no means clear that the energy so liberated comes from the breaking down of proteid material. Indeed, there is more reason for believing that the energy of muscular contraction comes primarily from the oxidation of non-nitrogenous matter. Nevertheless, custom and long experience sanction a high proteid diet, composed largely of meat or of other foodstuffs rich in nitrogen, for the development of that vigor and strength that go to make the accomplished athlete. For the development of new muscle tissue, to make two muscle fibres where before only one existed, to increase the number of available fibres, thereby adding to the bulk of the active tissue, a certain amount of proteid food is absolutely necessary, just as it is for all active tissues and organs of the body. But that this fact constitutes a satisfactory reason for the daily use of such quantities of proteid food as usually enter into the diet of the average athlete is very questionable.
As an illustration of the character of the diet frequently made use of by men doing prolonged muscular work, I may quote a few figures from an article by Professor W. O. Atwater[41]and H. C. Sherman on “The effect of severe and prolonged muscular work upon Food consumption, Digestion, and Metabolism,” in which are recorded observations made upon several professional bicycle riders during a six-day race. On one day subject “M” rode 334.1 miles, consuming for food onthat day meat extract, 311 grams; milk, 4937 grams; bread, 35 grams; boiled cereals, 877 grams; pastry, 142 grams; sugar, 53 grams; fruit, 2003 grams. His urine for the day contained 46.2 grams of nitrogen, corresponding to the metabolism of 288.7 grams of proteid matter. Subject “A” on one day rode 352.7 miles, taking as food, meat, 149 grams; meat extract, 24 grams; broth, 283 grams; eggs, 369 grams; butter, 78 grams; milk, 142 grams; malted milk, 78 grams; jelly, 213 grams; soup, 191 grams; bread, 361 grams; boiled cereal, 532 grams; sugar, about 400 grams; fruit, 933 grams; cocoa wine, 198 grams. His day’s urine contained 39.0 grams of nitrogen, corresponding to the metabolism of 243.7 grams of proteid material.
Obviously, if such high proteid metabolism as these figures imply is a necessary concomitant of vigorous or excessive muscular activity, then a rich proteid diet is needed to make good the loss of nitrogen to the body; but we are more inclined to believe that the large quantity of nitrogen excreted was the result chiefly of the high proteid ration, and only in small measure connected with the work done. With a sufficiency of non-nitrogenous food, the energy of muscular contraction does not come in any large degree from the breaking down of proteid matter, and there would seem to be no adequate reason for assuming a necessity for such rich and excessive proteid diet as athletes in training ordinarily adopt. Yet the contrary view is almost universally held and followed. As a prominent trainer said to the writer not long ago, “if the men are not fed on a rich meat diet and plenty of it, they will grow soft and lose their strength.”
With a view to testing some of these points and thereby broaden the scope of the investigation and enhance the value of the study, a group of eight students in the University, all trained athletes, was secured. These men volunteered to aid in the study, and at considerable self-sacrifice gave intelligent and hearty co-operation in all ways possible. The men were under observation from January 15, 1904, to the middle of June, 1904, a period of five months. From January 15 theurine was collected daily, and for a period of ten days the regular diet of the men was adhered to without any deviation whatever, with a view to ascertaining the extent of the proteid metabolism characteristic of each individual. No restrictions whatever in diet were suggested, but the ordinary food that the men were accustomed to eat while in training was taken. After this period the men were instructed to diminish somewhat the intake of proteid food, and in following out this plan most of the men diminished quite appreciably the quantity of food consumed at breakfast time, and in some cases stopped taking food of any kind at breakfast other than a cereal, with possibly coffee. No specific diet was imposed, but the men, being willing collaborators in the experiment, gradually cut down the intake of proteid food, diminishing likewise in considerable measure the total volume of food for the twenty-four hours.
STAPLETONPhotograph taken in the middle of the experiment, in April.
STAPLETON
Photograph taken in the middle of the experiment, in April.
The following brief description of the men, taken from Dr. Anderson’s report of their physical condition, to be referred to later, will suffice to make clear the characteristics (as athletes) of these subjects of study:
Mr. G. W. Anderson is a foot-ball, base-ball, and basket-ball player, as well as a crew man (not Varsity). Well built and an all round athlete. 26.5 years of age.
Mr. W. L. Anderson, a “Y” athlete (hurdler), the captain of the Yale Gymnastic Team, University Gymnastic Champion, and American Collegiate Gymnastic Champion. 21.5 years of age.
Mr. H. S. Bellis, a member of the Y. G. A., a gymnast and acrobat and in constant training. 26 years of age.
Dr. W. H. Callahan, Medical Assistant at the Gymnasium, in daily practice in the gymnasium; bowling, hand-ball, and running. 27 years of age.
Mr. M. Donahue, a very muscular and versatile athlete, a foot-ball player and a Varsity basket-ball player. 25 years of age.
Mr. C. S. Jacobus, a “Y” athlete, a noted long-distance man, and one of the best University runners. 22.3 years of age.
Mr. H. R. Schenker, an active member of the Y. G. A., a point winner and intercollegiate competitor in gymnastics. 22 years of age.
Mr. John Stapleton, a wrestler and gymnast. A professional, a man of large body and great strength. 24 years of age.
The results of the daily study of the twenty-four hours’ urine of each man for the entire period of five months are to be found in the accompanying tables. By a careful inspection of these data many interesting facts are brought to light. First it is to be observed, in harmony with what has already been stated regarding athletes, that the men, as a rule, were accustomed to the taking of large amounts of proteid food daily. Thus, during the preliminary period of ten days, Dr. Callahan excreted through the kidneys 22.79 grams of nitrogen as the daily average, corresponding to the metabolism of 142 grams of proteid matter per day, while on one day the nitrogen excretion reached the high figure of 31.99 grams, corresponding practically to the metabolism of 200 grams of proteid material.
G. W. Anderson, during the preliminary period of ten days—on his ordinary diet—showed an average daily excretion of 17.18 grams of nitrogen. W. L. Anderson in this same period excreted on an average 18.22 grams of nitrogen per day, while on one day the excretion reached 23.42 grams of nitrogen. Bellis showed an average daily excretion of 17.64 grams of nitrogen during this same fore period, while Stapleton excreted nitrogen at an average rate of 19.7 grams per day, thus indicating an average daily metabolism of 123 grams of proteid matter on his ordinary diet. With such data before us it is quite clear that we have here, as expected, a group of sturdy men accustomed to the taking of large amounts of proteid food daily; men who clearly believed that their strength and bodily vigor depended in large measure upon the ingestion and utilization of these quantities of proteid food.
After the termination of this preliminary period, the men began to diminish the amount of albuminous food. In doingthis they were at first given perfect freedom, each man following his own preferences, and making such alterations in his diet as he saw fit. The men were instructed as to the chemical composition of the various foodstuffs, so that they had a general idea of what foods were rich in nitrogen and could act accordingly. Some of the men cut down their intake of proteid food very rapidly, others made more gradual reduction. Some soon eliminated breakfast almost entirely. Others reduced the amount of food at each meal. Some of the men eliminated meat almost completely from their diet, and increased largely the intake of vegetable food. They were all advised, however, not to make too sudden a change in their diet, but to adopt a gradual reduction in the daily food as being less liable to disturb their physiological equilibrium. Naturally, the men knew exactly how much of a reduction in proteid food they were accomplishing each week, from the results of the chemical analysis of the urine. Further, the record of body-weight furnished evidence of how far the changes in diet were affecting body equilibrium, while their own feelings and ability to do their daily work constituted a check upon a too radical change in living. Careful perusal of the tables will show how far body-weight was changed, and to how great an extent proteid metabolism was reduced during the five months of the experiment.