Exertional-heat stress induced gastrointestinal perturbations: Prevention and management strategies

This thesis explored the effects of exertional-heat stress on gastrointestinal integrity, gastrointestinal symptoms and systemic responses; and the effectiveness of novel nutrition strategies for preventing gastrointestinal perturbations. Findings show that prolonged exertional-heat stress injures the intestinal epithelium, increases gastrointestinal symptoms, and perturbs systemic responses compared to physical exertion in temperate conditions. Frequent carbohydrate and protein intake during exertional-heat stress prevents intestinal injury and reduces permeability however, protein increases gastrointestinal symptoms. Frequent cold water ingestion may attenuate intestinal injury and upper-gastrointestinal symptoms. Combining carbohydrates with cold fluids will likely be most efficacious in supporting gastrointestinal health during prolonged exertional-heat stress.