Hypohydration affects forearm vascular conductance independent of heart rate during exercise

KENNEY. Hypohydration affects forearm vascular conductance independent of heart rate during exercise. J. Appl. Physiol. 73(4): 1232-1237, 1992.-Elevated body core temperature stimulates cutaneous vasodilation, which can be modified by nonthermal factors. To test whether hypohydration affects forearm vascu-lar conductance discretely from relative alterations in heart rate (HR), eight trained cyclists exercised progressively for 20 min each at 60,120, and 180 W [~22,37, and 55 % of maximal cycling 0, consumption (vo2 peak), respectively] in a warm hu-mid environment (dry bulb temperature 30°C; wet bulb temper-ature 24°C). Esophageal temperature and forearm blood flow were measured every 30 s, and mean arterial pressure and HR were measured at rest and during each exercise intensity (min-utes 15, 35, and 55). In the hypovolemic (HP) compared with the euvolemic (EU) state, blood volume was contracted by 24-