Individual Variability in the Core Interthreshold Zone as Related to Body Physique, Somatotype, and Physical Constitution

• Kakitsuba Naoshi

  Department of Environment and Technology, School of Science and Technology, Meijo University

• Mekjavic Igor B.

  Jozef Stefan Institute

• Katsuura Tetsuo

  Graduate School of Engineering, Chiba University

抄録

For evaluating the effect of body physique, somatotype, and physical constitution on individual variability in the core interthreshold zone (CIZ), data from 22 healthy young Japanese male subjects were examined. The experiment was carried out in a climatic chamber in which air temperature was maintained at 20–24°C. The subjects' body physique and the maximum work load were measured. Somatotype was predicted from the Heath-Carter Somatotype method. In addition, factors reflecting physical constitution, for example, susceptibility to heat and cold, and quality of sleep were obtained by questionnaire. The subjects wore a water-perfused suit which was perfused with water at a temperature of 25°C and at a rate of 600 cc/min, and exercised on an ergometer at 50% of their maximum work rate for 10–15 min until their sweating rate increased. They then remained continuously seated without exercise until shivering increased. Rectal temperature (T_re) and skin temperatures at four sites were monitored by thermistors, and sweating rate was measured at the forehead with a sweat rate monitor. Oxygen uptake was monitored with a gas analyzer. The results showed individual variability in the CIZ. According to the reciprocal cross-inhibition (RCI) theory, thermoafferent information from peripheral and core sensors is activated by T_re, mean skin temperature (T̅_sk), and their changes. Since T̅_sk was relatively unchanged, the data were selected to eliminate the influence of the core cooling rate on the sensor-to-effector pathway before RCI, and the relationship between the CIZ and the various factors was then analyzed. The results revealed that susceptibility to heat showed a good correlation with the CIZ, indicating that individual awareness of heat may change the CIZ due to thermoregulatory behavior.

収録刊行物

• Journal of PHYSIOLOGICAL ANTHROPOLOGY

  Journal of PHYSIOLOGICAL ANTHROPOLOGY 28 (6), 275-281, 2009

  日本生理人類学会

キーワード

• body temperature regulation
• core cooling rate
• shivering
• sweating
• core interthreshold zone

詳細情報

• CRID: 1390001205254172928
• NII論文ID: 110007482425
• NII書誌ID: AA12113950
• DOI: 10.2114/jpa2.28.275
• ISSN: 18806805
• ISSN: 18806791
• Web Site: http://dl.ndl.go.jp/info:ndljp/pid/10778813
• Web Site: https://search.jamas.or.jp/link/ui/2010138406
• 本文言語コード: en
• データソース種別:
  • JaLC
  • Crossref
  • NDL-Digital
  • CiNii Articles
• 抄録ライセンスフラグ: 使用不可