ETHANOL ACUTELY IMPAIRS GLYCOGEN REPLETION IN SKELETAL-MUSCLE FOLLOWING HIGH-INTENSITY SHORT-DURATION EXERCISE IN THE RAT

Ethanol is recognized to affect adversely carbohydrate metabolism in s keletal muscle. This paper seeks to establish whether ethanol acutely impairs glycogen repletion during recovery from high intensity short d uration exercise in the rat. High intensity exercise caused the massiv e mobilization of glycogen stores in muscles rich in type IIa and IIb fibres and marked increases in plasma and muscle lactate levels. Durin g the 30-minute recovery period, there was substantial glycogen replet ion in these muscles in both the ethanol-treated and control rats. Eth anol, however, was associated with reduced glycogen resynthesis in bot h the tibialis anterior (by 22%) and red gastrocnemius (by 31%) muscle s but not in the white gastrocnemius muscle. This reduction in post-ex ercise glycogen deposition was accompanied by decreased lactate dispos al and elevated plasma glucose levels. These effects of ethanol on gly cogen repletion may involve interactions with hepatic gluconeogenesis, glucose uptake and utilization in muscle, muscle glycogen synthesis a nd lactate glyconeogenesis. The ethanol-mediated impairment in post-ex ercise glycogen repletion may have important implications for the path ogenesis of chronic alcoholic skeletal myopathy.