Thermoregulation during exercise in the heat: strategies for maintaining health and performance.
Level 5 - mechanism / opinion, no new human data
Narrative review of physiology and preventive strategies without systematic methodology
PubMed 17645370 · doi:10.2165/00007256-200737080-00002
What was done
Narrative review evaluating the physiological mechanisms of heat dissipation during exercise, the thermoregulatory challenges imposed by hot and humid environments, and preventive strategies—specifically heat acclimatisation and fluid replacement protocols—to preserve athletic performance and reduce heat illness risk.
What was found
Over 75% of energy generated from skeletal muscle substrate oxidation is released as heat. In hot and humid conditions, heat exchange with the environment is impaired. Heat acclimatisation mitigates this by expanding plasma volume and lowering the core temperature thresholds for both cutaneous vasodilation and sweating onset. Nutritional strategies using fluid replacement beverages containing moderate amounts of glucose and sodium improve water absorption and fluid retention. No additional specific quantitative outcome data or effect sizes are reported in the abstract.
Why it matters
It summarizes how heat acclimatisation and tailored carbohydrate-electrolyte hydration support cardiovascular stability and thermal balance during physical exertion in hot conditions.
Limits
As a narrative review, it lacks systematic search criteria, meta-analytic pooling, and risk-of-bias assessment. Specific numerical guidelines (e.g., exact sodium concentrations, fluid volumes, acclimatisation protocols) and population boundaries are not provided in the abstract.
Cited by
- supports Repeated heat exposure causes heat acclimation, prompting the body to begin sweating at a lower core body temperature threshold.