Glutamine supplementation reduces markers of intestinal permeability during running in the heat in a dose-dependent manner.

Purpose: To examine the dose-response effects of acute glutamine supplementation on markers of gastrointestinal (GI) permeability, damage and, secondary, subjective symptoms of GI discomfort in response to running in the heat.

Methods: Ten recreationally active males completed a total of four exercise trials; a placebo trial and three glutamine trials at 0.25, 0.