期刊
JOURNAL OF APPLIED PHYSIOLOGY
卷 120, 期 6, 页码 615-623出版社
AMER PHYSIOLOGICAL SOC
DOI: 10.1152/japplphysiol.00906.2015
关键词
adiposity; biophysics; heat balance; sweating; temperature regulation
资金
- Natural Sciences and Engineering Research Council (NSERC) of Canada [86143-2010]
- Canadian Foundation for Innovation (CFI) Infrastructure Grant
- University of Ottawa Master's Scholarship
- Government of Australia Endeavour Postdoctoral Fellowship
We sought to determine 1) the influence of adiposity on thermoregulatory responses independently of the confounding biophysical factors of body mass and metabolic heat production (H-prod); and 2) whether differences in adiposity should be accounted for by prescribing an exercise intensity eliciting a fixed H-prod per kilogram of lean body mass (LBM). Nine low (LO-BF) and nine high (HI-BF) body fat males matched in pairs for total body mass (TBM; LO-BF: 88.7 +/- 8.4 kg, HI-BF: 90.1 +/- 7.9 kg; P = 0.72), but with distinctly different percentage body fat (% BF; LO-BF: 10.8 +/- 3.6%; HI-BF: 32.0 = 5.6%; P < 0.001), cycled for 60 min at 28.1 +/- 0.2 degrees C, 26 +/- 8% relative humidity (RH), at a target H-prod of 1) 550 W (FHP trial) and 2) 7.5 W/kg LBM (LBM trial). Changes in rectal temperature (Delta T-re) and local sweat rate (LSR) were measured continuously while whole body sweat loss (WBSL) and net heat loss (H-loss) were estimated over 60 min. In the FHP trial, Delta T-re (LO-BF: 0.66 +/- 0.21 degrees C, HI-BF: 0.87 +/- 0.18 degrees C; P = 0.02) was greater in HI-BF, whereas mean LSR (LO-BF 0.52 +/- 0.19, HI-BF 0.43 +/- 0.15 mg.cm(-2).min(-1); P = 0.19), WBSL (LO-BF 586 +/- 82 ml, HI-BF 559 +/- 75 ml; P = 0.47) and H-loss (LO-BF 1,867 +/- 208 kJ, HI-BF 1,826 +/- 224 kJ; P = 0.69) were all similar. In the LBM trial, Delta T-re (LO-BF 0.82 +/- 0.18 degrees C, HI-BF 0.54 +/- 0.19 degrees C; P < 0.001), mean LSR (LO-BF 0.59 +/- 0.20, HI-BF 0.38 +/- 0.12 mg.cm(-2).min(-1); P = 0.04), WBSL (LO-BF 580 +/- 106 ml, HI-BF 381 +/- 68 ml; P < 0.001), and H-loss (LO-BF 1,884 +/- 277 kJ, HI-BF 1,341 +/- 184 kJ; P < 0.001) were all greater at end-exercise in LO-BF. In conclusion, high % BF individuals demonstrate a greater Delta T-re independently of differences in mass and Hprod, possibly due to a lower mean specific heat capacity or impaired sudomotor control. However, thermoregulatory responses of groups with different adiposity levels should not be compared using a fixed Hprod in watts per kilogram lean body mass.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据