Effects of different heat acclimatization conditions on the physical activity of rats in hot and humid environment
10.3969/j.issn.1009-0754.2016.01.002
- VernacularTitle:不同热习服条件对大鼠湿热环境下运动能力的影响
- Author:
Yuxiang LI
1
;
Xinmin CHEN
;
Han LIANG
;
Heding AN
;
Wenling MA
;
Rengfei SHI
Author Information
1. 上海体育学院
- Keywords:
Hot and humid environment;
Exercise;
Heat acclimatization;
Rats
- From:
Journal of Navy Medicine
2016;37(1):4-8
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate the effects of different thermal conditions on the heat acclimatization and physical ability of rats in hot and humid environment .Methods Sixty-four male SD rats were randomly divided into 8 groups:the normal temperature and humidity rest group ( or the NTHR group );the normal temperature and humidity exercise group ( or the NTHE group );the normal temperature and high humidity rest group ( or the NTHHR group ); the normal temperature and high humidity exercise group ( or the NTHHE group);the high temperature and normal humidity rest group (or the HTNHR group); the high temperature and normal hu-midity exercise group ( or the NTNHE group );the high temperature and humidity rest group ( or the HTHR group ) and the high tem-perature and humidity exercise group (or the HTHE group), each consisting of 8 animals.Every day, the rats of the rest groups were left there at rest in the corresponding environment , while the rats of the exercise groups were first left there at rest for an hour , then had exercise at a load of 14 m/min for an hour for a succession of 14 days.Every day, all the rats were weighed both before and after exper-iment, the rate of weight loss was calculated and rectal temperature was taken the moment after the experiment was terminated .At day 16, all the rats had exercise at high temperature (36℃) and high humidity (85%) environment at a load of 28 m/min for 30 minutes. The number of the exhausted rats and exhaust time were recorded during exercise , and at the same time , the levels of rectal temperature were taken the moment after exhaust and when the exercise was terminated .At day 17, the number of rats that died of exhaust was cal-culated and recorded .Results In the course of heat acclimatization , the rate of weight loss at day 4 for all the animals groups except the groups at high temperature/rest began to decrease considerably (P<0.05).The rectal temperature of the animals in the high tem-perature/rest group and the high temperature/exercise group began to drop significantly at day 4(P<0.05).The rectal temperature and weight loss rate of the rats in the 4 exercise groups were significantly higher than those of the 4 rest groups (P<0.05).Furthermore, the rectal temperature of the HTHE group was significantly higher than that of the HTNHE group (P<0.05), however, there was no significant difference in the rate of weight loss , when comparisons were made between the two groups (P>0.05).Following physical exercise at high temperature and high humidity , the rectal temperature and the number of the rats with exhaust in the midst of the exer-cise and the number of deaths the next day in the HTNHE and HTHHE groups were significantly lower than those in the NTNHR and HTHHR groups (P<0.01).However, no significant differences could be seen between the HTNHE group and the HTHHE group (P>0.05).Conclusion Exercises at high temperature/high humidity and high temperature/normal humidity could achieve best heat accli-matization effect .From the standpoint of least effect on body temperature and weight loss , training at high temperature/normal humidity environment is a more appropriate heat acclimatization method .
