[Effects of voluntary exercise on nonspecific immunological mechanisms in mice]

We studied the effects of voluntary exercise on nonspecific immunological mechanisms in mice. In this study, 7 week old male ICR mice were divided into two groups: a non-exercise group (control) and a group given voluntary exercise (Vex group). Each mouse of the Vex group was kept in an individual cage equipped with a voluntarily revolving wheel that the mouse had free access to. The duration of voluntary exercise was 3 days per week for 8 weeks. The following results were obtained: 1) After 8 weeks of voluntary exercise, food consumption, the weight of the anterior tibialis muscle and succinate dehydrogenase activity in the anterior tibialis muscle increased significantly in the Vex group compared to the control group. 2) By means of the carbon clearance method, phagocytosis of the reticuloendothelial system was increased in the Vex group. 3) Glucose consumption capacity and O-2 production capacity of peritoneal macrophages (M phi) were significantly increased in the Vex group compared to the control group. 4) The acid phosphatase (APH), beta-glucuronidase (GLU) and lactate dehydrogenase (LDH) activities of peritoneal M phi increased significantly in the Vex group. 5) Concanavalin A (Con A)-induced cell proliferation in the spleen was high in the Vex group. Based on the above findings, it may be surmised that voluntary exercise enhances nonspecific immunological mechanisms and thereby improves the host defense mechanisms in mice.