Lipid metabolite responses to diet and training in sled dogs

Two groups of Alaskan Huskies were fed either a high fat (HFD) or a high carbohydrate diet 4 wk before and during an 8-wk conditioning program. Aerobic bouts of exercise were performed before and after conditioning. Blood samples taken before and after each exercise test were analyzed for serum concentrations of free fatty acids (FFA), triglycerides (TG), vitamin E, glucose and serum lipase activity. The post-exercise FFA and TG values were greater in the HFD group both before and after training. There were no significant differences in plasma vitamin E or in serum lipase activity between diet groups. It is concluded that after an adequate period of adaptation, prolonged feeding of a HFD safely enhances the availability of local and peripheral lipid stores during exercise. Although the elevated levels of FFA and TG associated with HFD suggest enhanced potential for performance, further study of more prolonged and possibly more intense exercise is necessary to confirm this theory.