We found a match
Your institution may have rights to this item. Sign in to continue.
- Title
Influence of adiposity on cooling efficiency in hyperthermic individuals.
- Authors
Lemire, Bruno; Gagnon, Daniel; Jay, Ollie; Dorman, Lucy; DuCharme, Michel B.; Kenny, Glen P.
- Abstract
This study evaluated the effect of body adiposity on core cooling rates, as measured by decreases in rectal (T (re)), esophageal (T (es)) and aural canal (T (ac)) temperatures, of individuals rendered hyperthermic by dynamic exercise in the heat. Seventeen male participants were divided into two groups; low body fat (LF, 12.9 +/- 1.9%) and high body fat (HF, 22.3 +/- 4.3%). Participants exercised at 65% of their maximal oxygen uptake at an ambient air temperature of 40 degrees C until T (re) increased to 40 degrees C or until volitional fatigue. Following exercise, participants were immersed up to the clavicles in an 8 degrees C circulated water bath until T (re) returned to 37.5 degrees C. No significant differences were found between the LF and HF in the time to reach a T (re) of 39.5 degrees C (P = 0.205), 38.5 degrees C (P = 0.343) and 37.5 degrees C (P = 0.923) during the immersion. Overall cooling rate for T (re) was also similar between groups (0.23 +/- 0.09 degrees C/min (LF) vs. 0.20 +/- 0.09 degrees C/min (HF), P = 0.647) as well as those for T (es) (P = 0.502) and T (ac) (P = 0.940). Furthermore, mean rate of non-evaporative heat loss (702 +/- 217 W/m(2) (LF) vs. 612 +/- 141 W/m(2) (HF), P = 0.239) was not different between groups. These results suggest that a difference of approximately 10% of body adiposity does not affect core cooling rates in active individuals under 25% body fat rendered hyperthermic by exercise.
- Subjects
OBESITY; NUTRITION disorders; EATING disorders; OVERWEIGHT persons; FATIGUE (Physiology); METABOLIC disorders; ADIPOSE tissues; BODY temperature regulation; HUMAN body composition; COLD (Temperature); COMPARATIVE studies; EXERCISE; FEVER; PHYSIOLOGICAL effects of heat; RESEARCH methodology; MEDICAL cooperation; MUSCLE contraction; RESEARCH; WATER; EVALUATION research; OXYGEN consumption; SKELETAL muscle; MUSCLE fatigue
- Publication
European Journal of Applied Physiology, 2008, Vol 104, Issue 1, p67
- ISSN
1439-6319
- Publication type
journal article
- DOI
10.1007/s00421-008-0780-0