Yoshimitsu Inoue

Sweating responses and the muscle metaboreflex under mildly hyperthermic conditions in sprinters and distance runners

To investigate the effects of different training methods on nonthermal sweating during activation of the muscle metaboreflex, we compared sweating responses during postexercise muscle occlusion in endurance runners, sprinters, and untrained men under mild hyperthermia (ambient temperature, 35°C; relative humidity, 50%). Ten endurance runners, nine sprinters, and ten untrained men (maximal oxygen uptakes: 57.5 ± 1.5, 49.3 ± 1.5, and 36.6 ± 1.6 ml·kg(-1)·min(-1), respectively; P < 0.05) performed an isometric handgrip exercise at 40% maximal voluntary contraction for 2 min, and then a pressure of 280 mmHg was applied to the forearm to occlude blood circulation for 2 min. The Δ change in mean arterial blood pressure between the resting level and the occlusion was significantly higher in sprinters than in untrained men (32.2 ± 4.4 vs. 17.3 ± 2.6 mmHg, respectively; P < 0.05); however, no difference was observed between distance runners and untrained men. The Δ mean sweating rate (averaged value of the forehead, chest, forearm, and thigh) during the occlusion was significantly higher in distance runners than in sprinters and untrained men (0.38 ± 0.07, 0.19 ± 0.03, and 0.11 ± 0.04 mg·cm(-2)·min(-1), respectively; P < 0.05) and did not differ between sprinters and untrained men. Our results suggest that the specificity of training modalities influences the sweating response during activation of the muscle metaboreflex. In addition, these results imply that a greater activation of the muscle metaboreflex does not cause a greater sweating response in sprinters.

Sex differences in acetylcholine-induced sweating responses due to physical training.

PurposeThe present study examined sex differences in the sweat gland response to acetylcholine (ACh) in physically trained and untrained male and female subjects.MethodsSweating responses were induced on the forearm and thigh in resting subjects by ACh iontophoresis using a 10% solution at 2xa0mA for 5xa0min at 26°C and 50% relative humidity.ResultsThe ACh-induced sweating rate (SR) on the forearm and thigh was greater in physically trained male (Pu2009<u20090.001 for the forearm and thigh, respectively) and female (Pu2009=u20090.08 for the forearm, Pu2009<u20090.001 for the thigh) subjects than in untrained subjects of both sexes. The SR was also significantly greater in physically trained males compared to females at both sites (Pu2009<u20090.001) and in untrained males compared to females on the thigh (Pu2009<u20090.02) only, although the degree of difference was greater in trained subjects than in untrained subjects. These sex differences can be attributed to the difference in sweat output per gland rather than the number of activated sweat glands.ConclusionWe conclude that physical training enhances the ACh-induced SR in both sexes but that the degree of enhancement is greater in male than in female subjects. The effects of physical training and sex on the SR may be due to changes in peripheral sensitivity to ACh and/or sweat gland size.

Characteristics of sweating responses and peripheral sweat gland function during passive heating in sprinters

The purpose of this study was to compare sweating function in sprinters who have trained for several years with untrained subjects and trained endurance runners. Two separate experiments were conducted. Nine sprinters, eight untrained men, and nine distance runners (

Changes in eccrine sweating on the glabrous skin of the palm and finger during isometric exercise

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Sweating response to passive stretch of the calf muscle during activation of forearm muscle metaboreceptors in heated humans

50.9xa0±xa01.4, 38.2xa0±xa01.8, and 59.1xa0±xa01.2xa0mL/kg/min, respectively; Pxa0<xa00.05) were passively heated for 50xa0min (Experiment 1), and ten sprinters, 11 untrained men and nine distance runners (similar

Influence of exercise training with thigh compression on heat‐loss responses

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