Introductory Remarks:
Part 26 provides an overview of three supplements with different characteristics of potential contribution to exercise performance and different levels of scientific support for this potential. Methionine is an amino acid with an important role, in addition to its contribution to protein metabolism, namely, as a precursor of creatine. N-acetylcysteine has an important role in glutathione resynthesis and therefore contributes to antioxidant status. Finally, we discuss a new approach to providing carbohydrates in sports supplements – known as multiple transportable carbohydrates (MTC) – which overcomes the usual intestinal absorption limits to allow higher rates of carbohydrate consumed during exercise to be available as a muscle fuel.