Effect of time after feeding and carbohydrate or water supplement on work in dogs

¹ Quartermaster Food and Container Institute for the Armed Forces, U.S. Army, Chicago, Illinois

Effects of proximity of the last meal and post-absorptive supplementation with water or carbohydrate were examined in reference to aerobic work performance in the dog. In the first series, performance was measured utilizing a standard 40-minute period of treadmill running adjusted to a work load of 202.9 kg-m/min. administered 1 , 4, 6 and 24 hours following the intake of a normal meal. On the average, minute pulse rate was significantly nine beats higher and body temperature 0.75°F higher at 4 and 6 hours following the meal. There was no significant effect on energy expenditure due to specific dynamic action of the food. Maximum aerobic work capacity was studied. Provision of 1.5 liters of water during work markedly improved (+80%) performance, whereas provision of carbohydrate just prior to work was without immediate benefit. Increased work capacity due to water supplementation is mediated by the maintenance of a relatively normal state of hydration, improvements in temperature regulation and a beneficial effect on carbohydrate metabolism.