We identified the cardiovascular stress encountered by superimposing dehydration on hyperthermia during exercise in the heat and the mechanisms contributing to the dehydration-mediated stroke volume (SV) reduction. Fifteen endurance-trained cyclists [maximal O2 consumption (VO2max) = 4.5 l/min] exercised in the heat for 100-120 min and either became dehydrated by 4% body weight or remained euhydrated [...]

No abstract available.

No abstract available.

During exercise, sweat output often exceeds water intake, producing a water deficit or hypohydration. The water deficit lowers both intracellular and extracellular fluid volumes, and causes a hypotonic-hypovolemia of the blood. Aerobic exercise tasks are likely to be adversely effected by hypohydration (even in the absence of heat strain), with the potential affect being greater [...]

Gastrointestinal distress is commonly reported by athletes after ingestion of a beverage. We speculate that ingestion may be occurring after dehydration has taken place. The high prevalence of GI disorders in marathon runners who have lost greater than or equal to 4% body weight supports this theory. To test this theory, the effects of dehydration, [...]

During exercise in the heat, sweat output often exceeds water intake, which results in a body water deficit or hypohydration. This water deficit occurs from both the intracellular and extracellular fluid compartments, and causes a hypertonic-hypovolemia of the blood. Aerobic exercise tasks are likely to be adversely affected by hypohydration; and the warmer the environment [...]

No abstract available.

No abstract available.

The influence of hyperhydration on thermoregulatory function was tested in 8 male volunteers. The subjects performed cycle exercise in the upright position at 52% Vo2max for 45 min in a thermoneutral (Ta = 23 degrees C) environment. The day after the control exercise the subjects were hyperhydrated with tap water (35 ml X kg-1 of [...]

No abstract available.