Co-enzyme A (CoASH) and carnitine fulfil several vital roles in the catabolism of both fat and carbohydrate within skeletal muscle. During exercise when the competition between the two metabolic pathways for the involvement of CoASH and carnitine is increased, their relative availability may play major roles in skeletal muscle fuel selection. However, the direct roles of CoASH and carnitine in muscle fuel selection during exercise have not been closely investigated in humans. This publication documents the first attempts to increase muscle CoASH content in humans, and the first demonstration...