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Body temperature during treadmill running was studied in six dogs at seven different grades from 0–22 degrees of inclination. The replicate variability in the work rectal, skin and fur temperature was ±0.5℉, ±1.4℉ and ±1.3℉, respectively. At grades up to 12 degrees of inclination there is a prolonged steady state in the rectal temperature. At higher grades there is a progressive increase in rectal temperature with running time. Body surface temperatures show little affect at the lower grades. At higher work intensities there is an increase in skin and fur temperature. Maximum heat storage varied from 21.3–41.3 Cal. during short term exhaustive work. This type of calculation is discussed critically. The relationship between rate of rise in rectal temperature and maximum performance time was studied. Without regard to work load a product-moment correlation coefficient of +0.991 was found. Submitted on September 17, 1958

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Effect of food deprivation on endurance capacity was studied in dogs under the following conditions: a) 3 and 5 days of fasting with daily high levels of energy expenditure and b) 15 days of fasting with low daily levels of energy expenditure. Relative maximum performance, i.e. endurance capacity under conditions wherein work dehydration is a limiting factor, is unaffected by 10–15% body-weight loss and hypoglycemia induced by acute food deprivation. Even with weight loss up to 22%, capacity for daily moderate levels of work is well maintained. Absolute maximum performance (water provided exhaustive treadmill running) improves with 5 days of fasting. Associated with 74% increase in endurance capacity, there is an increased mobilization of body tissue for fuel for the working muscles and a large increase in the post-exercise blood glucose concentration. The dog is resistant to starvation ketosis. In animals tested for absolute performance capacity, the average cumulative calorie deficit, including the exhaustive running trial, was 7500 Calories; yet there was no significant change in the level of blood acetone. It is concluded that absolute performance in the dog increases with 5 days of food deprivation; this response is mediated by a unique permissive effect of such treatment particularly on ability to mobilize body energy reserves. Submitted on April 17, 1959