Exertional hyperthermia: body core temperature above 39-40°C
IntensityElevation of body core temperature beyond 39°C during effort, a major physiological risk in hot climates.
Exertional hyperthermia occurs when metabolic heat production (80% of energy used by muscles degrades to heat) exceeds dissipation capacity via sweat and convection. It develops progressively, with core temperature rising 0.1-0.2°C per 10 min of running in hot climate. Severity signs: headache, confusion, hot red skin without sweating, tremors, nausea. Beyond 40°C core, risk of exertional heat stroke, medical emergency. Risk factors: ambient temperature >25°C, humidity >70%, no prior acclimatization, dehydration, hyperventilation. Prevention: heat acclimatization 10-14 days before hot race, pre-cooling with ice slush or ice pack at race start, hydration with electrolytes, pace reduced by 5-15 sec/km depending on condition severity.
In TriPaced:
TriPaced does not yet auto-prescribe heat acclimatization. Practically: if your race is expected above 25°C and you do not train in those conditions, plan 10-14 days of progressive exposure (20 min sauna, late afternoon covered sessions, unventilated home trainer) 2-3 weeks before the race. The glossary term 'chaleur' provides race strategies in hot climate.
Source Racinais S et al., 2015: Consensus recommendations on training and competing in the heat, Sports Medicine