Effects of Body Cooling during Exercise on Physiological Responses
【Supercategory：7. DESCENTE SPORTS SCIENCE Subcategory：7.7 Vol.7】
The purpose of this study was to observe the effects of body cooling during submaximal exercise on thermoregulatory responses. Nine healthy male subjects pedalled a bicycle ergometer at the work rate of 55% VO²max for 60 minutes, under the temperature condition: ambient temperature, 24°C and room humidity, 50%.
The subjects were cooled by means of cold packs (147 cm²) for 5 minutes. During exercise, the cooling was performed every 15 minutes through the following procedures 1) a 5-minute's cooling of forehead skin after the initial 15 minutes of exercise, 2) a 5-minute's cooling of lumbodorsal skin after 30 minutes of exercise, 3) a 5-minute's cooling of both forehead and lumbodorsal skin after 45 minutes of exercise. For the recovery period, another 5-minute cooling was given to both forehead and lumbodorsal skin, starting from 5 minutes after the exercise was over.
The results are summarized as follows:
1) The rate of increase in ear canal (Tear) and rectal (Tre) temperatures was slightly reduced by the forehead cooling during exercise. However, as for mean skin (Tsk) and mean body (Tb) temperatures and heat storage, there were no obvious effects of the cooling.
2) The rate of increase in Tear, Tre and Tsk was reduced in the experiments for the lumbodorsal cooling and the forehead and lumbodorsal cooling during exercise.
3) Loss of body weight during exercise was approximately 1.1% of the total body weight. No noticeable relationship was observed between body cooling and sweat rate.
4) The rising of heart rate during exercise was slightly inhibited by the series of body cooling.
5) Both forehead and lumbodorsal cooling gave no immediate effects on a decrease of deep temperatures during the recovery period, but elicited a reduction of heat storage as a result of the large decreased rate of Tsk.
The above results suggest that the increases of body temperature and heart rate were restrained by body cooling during submaximal exercise.
DESCENTE SPORTS SCIENCE Vol.7/THE DESCENTE AND ISHIMOTO MEMORIAL FOUNDATION FOR THE PROMOTION SPORTS SCIENCE
The subjects were cooled by means of cold packs (147 cm²) for 5 minutes. During exercise, the cooling was performed every 15 minutes through the following procedures 1) a 5-minute's cooling of forehead skin after the initial 15 minutes of exercise, 2) a 5-minute's cooling of lumbodorsal skin after 30 minutes of exercise, 3) a 5-minute's cooling of both forehead and lumbodorsal skin after 45 minutes of exercise. For the recovery period, another 5-minute cooling was given to both forehead and lumbodorsal skin, starting from 5 minutes after the exercise was over.
The results are summarized as follows:
1) The rate of increase in ear canal (Tear) and rectal (Tre) temperatures was slightly reduced by the forehead cooling during exercise. However, as for mean skin (Tsk) and mean body (Tb) temperatures and heat storage, there were no obvious effects of the cooling.
2) The rate of increase in Tear, Tre and Tsk was reduced in the experiments for the lumbodorsal cooling and the forehead and lumbodorsal cooling during exercise.
3) Loss of body weight during exercise was approximately 1.1% of the total body weight. No noticeable relationship was observed between body cooling and sweat rate.
4) The rising of heart rate during exercise was slightly inhibited by the series of body cooling.
5) Both forehead and lumbodorsal cooling gave no immediate effects on a decrease of deep temperatures during the recovery period, but elicited a reduction of heat storage as a result of the large decreased rate of Tsk.
The above results suggest that the increases of body temperature and heart rate were restrained by body cooling during submaximal exercise.
DESCENTE SPORTS SCIENCE Vol.7/THE DESCENTE AND ISHIMOTO MEMORIAL FOUNDATION FOR THE PROMOTION SPORTS SCIENCE
| Researcher | Kazutaka Fujishima, Tetsuro Ohgaki, Toshie Komuro |
|---|---|
| University or institution | Kyushu University |
Keywords
body cooling, submaximal exercise, thermoregulatory responses