EXPERIMENTAL STUDIES ON THE ABDOMINAL PAIN DURING EXERCISE

Abstract

I. Aim and Method
The cause of the stabbing pain in the side during exercise is not definitely known for the physiologist cannot be sure its appearance when he is prepared to study it. Therefore, in order to reveal the cause of this abdominal pain, the authors carried out first an investigation, then, on the basis of the result of the investigation, made attempt to induce the pain in the two series of experiments without any drug, balloon and so on.
In the investigation, the questionnares were distributed to the 200 young male athletes to know about their experience of the abdominal pain during exercise and about the relations between the pain and weather, physical condition, kind of exercise and eating-exercise time interval.
In the first series of experiments, eight healthy male students have not the history of an alimentary disorder were selected as the subject. Each subject came to the laboratory after fasting for eight and over hours, then they were loaded one of the two intensities of running on a treadmill in accordance with the procedure as showed in Tab. 1.
In the second series of experiments, six of the eight subjects of the first series of experiments were selected as the subject for they complained the pain during running which carried out immediately after drinking or eating. Each subject was loaded walking on a treadmill and cycling on a bicycle ergometer in accordance with the procedure as showed in Tab.2. And this cycling requires about the same oxygen cost as the running at 240meters per minute.
The test meal was consisted of baked egg (200g), fish ham (50g), raw cabbage (50g) and boild rice, and before the drinking or eating, each subject was advised to take water or boild rice as much as possible.
When the subject complained the pain during exercise, the exercise was stopped about one minute later.
II. Result and Conclusion.
The pain was found 24 cases during running and only one case during cycling. In 72% of these 25 cases, a great deal of abdominal gas and excreta was found, and in 42% of 31 cases which were not found the pain, a great deal of abdominal gas and excreta was also found. Most of regions of the pain were middle and lower abdomen (80%), and specially in the experiments carried out relatively short time after eating, most of regions of the pain were left side abdomen (86%) .
As for the time interval between the eating and exercise, the shorter the time interval, the higher rate of the pain was found.
In every case, the pain stopped within seven minutes after exercise and any effect on the body was not found.
From the result described above, it may conclude that the staple causes of the abdominal pain during exercise are (1) the abdominal gas or excreta is concentrated locally in the stomach or intestin by the movement of the body during exercise and distends the diaphragm or intestin, and (2) the stomach or intestin which is enlarged by the substances is rocked and tossed by the movement of the body during exercise and stimulates physically or chemically (local anaemia) to the mesentery or interior organs and so on.