标题:The Different Effects of Fluid with and without Carbohydrate Ingestion on Subjective Responses of Untrained Men during Prolonged Exercise in a Hot Environment
期刊名称:Journal of Nutritional Science and Vitaminology
印刷版ISSN:0301-4800
电子版ISSN:1881-7742
出版年度:2009
卷号:55
期号:6
页码:506-510
DOI:10.3177/jnsv.55.506
出版社:Center for Academic Publications Japan
摘要:This study examined the effects of maintaining euhydration by ingesting fluids with or without carbohydrate on subjective responses of untrained men during prolonged exercise in a hot environment. Six healthy untrained subjects completed 90 min of cycling exercises at 55% maximal oxygen consumption (VO2max) in a hot environment (temperature: 28oC, humidity: 50%) under three different experimental conditions. During the first trial, subjects did not ingest fluids during exercise (dehydration (DH) trial). In the second and third trials, subjects received mineral water (MW) and hypotonic fluid containing carbohydrate (HF), respectively, in amounts equaling their weight loss in the DH trial. At the end of exercise, the overall rating of perceived exertion (RPE-O) was lower in the MW and HF trials than in the DH trial (14.3±1.0 and 13.7±0.6 vs 17.7±1.0, p <0.05, respectively). RPE-cardiovascular and RPE-legs were lower at the end of exercise in the HF trial compared with the DH trial. VO2, heart rate (HR), and rectal temperature increased during exercise in the three trials. At the end of exercise, the drift in VO2 was lower in the MW and HF trials than in the DH trial (304±41 and 339±40 vs 458±33 mL, p <0.05, respectively). HR at the end of exercise in the HF trial was lower than in the DH trial (158±5 vs 173±7 bpm, p <0.05). These results suggest that maintaining euhydration during prolonged exercise in untrained men could attenuate RPE-O and that hypotonic electrolyte-carbohydrate solution could attenuate RPE-legs during exercise.