Influence of creatine monohydrate ingestion on muscle metabolites and intense exercise capacity in individuals with multiple sclerosis.

To evaluate the effectiveness of ingesting creatine monohydrate in elevating intramuscular creatine stores and improving exercise capacity in individuals with multiple sclerosis (MS). Randomized, double-blind, placebo-controlled, pre-posttrial. A university-based exercise physiology laboratory. Sixteen individuals with relapsing-remitting MS (median Expanded Disability Status Scale score, 4.75; range, 1.5-6.0). Eight individuals with MS were randomized to the creatine group (20g/d of creatine monohydrate for 5d), and 8 others were randomized to the placebo group. Needle biopsies were performed on the vastus lateralis at rest before and after treatment. Subjects performed 3 bouts of 30 maximal knee extensions and flexions at 180 degrees /s with 1 minute of recovery between bouts before and after treatment. Intramuscular total creatine, phosphocreatine, free creatine, and total work output. Creatine ingestion did not significantly elevate intramuscular total creatine, phosphocreatine, or free creatine or improve total work production. Creatine ingestion had no significant effect on muscle creatine stores or high-intensity exercise capacity in individuals with MS.