The different effects of fluid with and without carbohydrate ingestion on subjective responses of untrained men during prolonged exercise in a hot environment

Toshimichi Ishijima, Hideki Hashimoto, Katsuhiko Satou, Isao Muraoka, Katsuhiko Suzuki, Mitsuru Higuchi

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

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 (V O2max) in a hot environment (temperature: 28°C, 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). RPEcardiovascular 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.

Original languageEnglish
Pages (from-to)506-510
Number of pages5
JournalJournal of Nutritional Science and Vitaminology
Volume55
Issue number6
DOIs
Publication statusPublished - 2009 Dec 1

Keywords

  • Heat exposure
  • Maintaining euhydration
  • Perceived exertion
  • Prolonged exercise

ASJC Scopus subject areas

  • Medicine (miscellaneous)
  • Nutrition and Dietetics

Fingerprint Dive into the research topics of 'The different effects of fluid with and without carbohydrate ingestion on subjective responses of untrained men during prolonged exercise in a hot environment'. Together they form a unique fingerprint.

  • Cite this