Individual variations among Egyptian men in heat tolerance

ABSTRACT

The Effect of 1.5-hr exposure of men to high ambient temperature [39.5 degree] on body temperature [BT], respiration rate [RR], pulse rate [PR], systolic blood pressure [SBP], diastolic blood pressure [DBF] and pulse pressure [PP], was studied on 23 adult Egyptian men during summer when the subjects were normally acclimatized to heat. BT, RR and PR means were higher under heat stress [P < 0.005] as compared to those under mild climate [25degree]. The means were 36.85 degree, 19.1 rpm and 79.8 ppm, respectively for mild climate and were 37.28 degree, 22.7 rpm and 87.3 ppm, respectively for hot climate. BP was not affected significantly by heat whereas, PP decreased [P< 0.05]. The mean of SBP, DBP and PP under thermoneutral temperature were 109.72 and 37.4 mm HG, respectively, while they were under hot climate 107, 73, and 33.7 mm.Hg, respectively. The coefficient of variations of the heat-induced changes in BT, RR, PR, SBP, DBP and PP were great being 33 percent, 94 percent, 526 percent, 489 percent and 153 percent, respectively indicating wide individual variations among Egyptian men in heat tolerance