The American Football Uniform: Uncompensable Heat Stress and Hyperthermic Exhaustion

Hyperhydration: tolerance and cardiovascular effects during uncompensable exercise-heat stress.

This study examined the efficacy of glycerol and water hyperhydration (1 h before exercise) on tolerance and cardiovascular strain during uncompensable exercise-heat stress. The approach was to determine whether 1-h preexercise hyperhydration (29.1 ml H2O/kg lean body mass with or without 1.2 g/kg lean body mass of glycerol) provided a physiological advantage over euhydration. Eight heat-acclim...

Heat acclimation, aerobic fitness, and hydration effects on tolerance during uncompensable heat stress.

The purpose of the present study was to determine the separate and combined effects of aerobic fitness, short-term heat acclimation, and hypohydration on tolerance during light exercise while wearing nuclear, biological, and chemical protective clothing in the heat (40 degrees C, 30% relative humidity). Men who were moderately fit [(MF); <50 ml . kg-1 . min-1 maximal O2 consumption; n = 7] and ...

Youth football: heat stress and injury risk.

Low doses of melatonin and diurnal effects on thermoregulation and tolerance to uncompensable heat stress.

This study examined whether the reported hypothermic effect of melatonin ingestion increased tolerance to exercise at 40 degrees C, for trials conducted either in the morning or afternoon, while subjects were wearing protective clothing. Nine men performed four randomly ordered trials; two each in the morning (0930) and afternoon (1330) after the double-blind ingestion of either two placebo cap...

Physiological tolerance to uncompensable heat stress: effects of exercise intensity, protective clothing, and climate.

This study determined the influence of exercise intensity, protective clothing level, and climate on physiological tolerance to uncompensable heat stress. It also compared the relationship between core temperature and the incidence of exhaustion from heat strain for persons wearing protective clothing to previously published data of unclothed persons during uncompensable heat stress. Seven heat...