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I. Two experimental groups, each of thirteen boarding schoolboys, were given either 400 mg a-tocopheryl acetate or placeboes daily in addition to their normal diet during training in swimming and various athletic activities over a period of 6 weeks. Evaluation of the experimental treatments was made from tests of anthropometric status, cardiorespiratory efficiency and motor fitness and performance, which were administered at the beginning and end of the experimental period.2. Whereas training significantly improved physiological function and performance in bothRelationships between diet and athletic performance were studied, or accepted without study, long before nutrition became a science. Often, these relationships have been based on practical considerations and were merely the outcome of common sense. Some of the relationships proposed, however, have been largely imaginary and rooted in the particular fads of athletes or their trainers. Such rituals have led sportsmen to contemplate the possibility of supercharging the body by the provision of a diet containing an unusual abundance of those nutrients which have either a direct or an indirect effect on muscular performance. It has been hoped thereby to raise the athletic performance above that possible on a standard diet.Vitamin E has for long attracted especial interest in this direction for three main reasons.First, in many species of animal its deficiency causes the muscles to become dystrophic. It is tempting, therefore, to assume that when the muscles are under severe stress their demand for vitamin E may be increased and may not be satisfied by the amounts supplied in a normal diet. Not that a deficiency of the vitamin would cause dystrophy, but it could result in lower muscular performance than would be possible if the intake of vitamin E were greater.Secondly, there is convincing evidence that in experimental animals the resistance to hypoxia and hyperoxia can be affected by the vitamin E status (Hove, Hickman & Harris, 1945; Taylor, 1953). This finding may be correlated with the ability of the * Present address :

Chemical estimations of the tocopherols present in wheaten flours treated with chlorine dioxide, or untreated, have been made by a method which allows the separation of the different forms of the vitamin. The chlorine dioxide caused almost complete destruction of each of the tocopherols. Biological tests demonstrated that untreated flour, when included as the main component of the diet of rats, contains enough tocopherol to satisfy their requirements. Rats developed various signs of avitaminosis E, however, when they were given a similar diet containing flour which had been treated with chlorine dioxide. Enough tocopherol survived during the baking of bread from untreated flour to suffice the requirements of rats. Improvement with potassium bromate or ascorbic acid did not appear to decrease the tocopherol content of bread, but some destruction was caused by the aeration process of breadmaking.

Abstract— The incorporation of 14C into amino acids of the brain was determined at different times after injection of [U‐14C]glucose and [U‐14C]ribose to rats maintained on thiamine‐supplemented and thiamine‐deficient diets for 22 days. The 14C‐content of amino acids in the brain of thiamine‐deficient rats decreased at times 2–10 min after injection of [U‐14C]glucose. but it increased at 2 min and decreased at times 5–10 min after injection of [U‐14C]ribose. The results of labelling of amino acids indicated that the activities in vivo of the thiamine pyrophosphate requiring enzymes, pyruvate oxidase, a‐oxoglutarate dehydrogenase and transketolase were similar in the two groups. It was suggested that the observed decrease in the labelling of amino acids was due to one or more of the following factors: (i) a decrease in the activities of glycolytic enzymes catalysing the conversion of glucose into triose phosphate; (ii) a decrease in the transport of substrate to the active site of the enzymes; or (iii) altered neurohistopathology of the brain. Thiamine deficiency in rats showed a 5% decrease in glutamate (P < 0–05), 46% decrease in threonine (P < 0001) and 16% increase in glycine (P < 0–01) content of the brain.

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The work to be described in these communications followed earlier studies (Leitner & Moore, 1946;Leitner, Moore & Sharman, 1947), which were mainly concerned with the lowered blood vitamin A in certain diseases. For purposes of comparison it was desired to know the levels of vitamin A prevalent in normal subjects, and the advisability of obtaining more adequate information became apparent. It was known that the blood vitamin A varied widely in different normal individuals, and that men tended to have higher levels than women (Kimble, 1938-9), but knowledge was scanty on the influence of age or season of the year. Moreover, at the time of our earlier work, dietary restrictions, imposed during the Second World War, were still in force in this country. It was of interest, therefore, to study the effect on the blood vitamin A of the changes in the national food supplies which followed the gradual relaxation of controls.Specimens of blood were taken for a long period from numerous subjects, with the aim of collecting a mass of information large enough to counteract the disturbing effect on averages of the wide individual variations. Estimations of total carotenoids were made parallel with those of vitamin A. Vitamin E is known to be capable of intervening in the metabolism of vitamin A (Moore, 1939; Bacharach, 1940; Harris & Woodside, 194z), so our programme was extended to include estimations of vitamin E. The presentation of our results on vitamin E has, however, been assigned to a later communication (paper no. 2 of this series), and paper no. 3 will deal with observations on chronic hospital patients. E X P E R I M E N T A LCollection of specimens. Blood was collected by venepuncture from volunteers who came to one of us (2. A. L.) for medical examination. Some were young men in good health, who were examined for purposes of life insurance or for their fitness to do arduous work abroad. Most of the subjects, however, had some complaint, and were examined with a view to diagnosis and treatment.

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