Abstract

The effect of forced liquid (L) or solid (S) carbohydrate (CHO)-rich feedings on plasma glucose, insulin, and glycogenesis after glycogen depletion was investigated. The relationship between glycogen restoration and maximal physical working capacity (MPWC) was studied as well. Eight males performed two experiments, with 2 weeks interval on a bicycle ergometer. In each experiment, MPWC was determined in a graded test, which was immediately followed by interval work until exhaustion. After exercise cessation (EC), the subjects started to consume a standardized amount of concentrated L or CHO-rich food. Insulin and glucose concentration in blood were determined. Muscle was determined before, immediately after, 5 h after, and 22 h after EC. MPWC was determined again 22 h after EC. Four subjects performed a third experiment, in which solid food consumption was left ad libitum (AL). A rapid glycogen repletion was found 5 h after EC. The higher plasma glucose and insulin levels during the 5 h after EC in the S experiments did not elicit a difference in glycogen repletion. Glycogen synthesis rate in the AL experiment was lower than in the L and S experiments. Glycogen restoration in the L and S experiments was complete 22 h after depletion. However, despite repletion of glycogen, MPWC was decreased in both experiments. This indicates that recovery of physical performance after exhaustive exercise includes more than repletion of glycogen. Verf.-Referat