A study was conducted to investigate the effects of voluntary exercise, and the relationship between the quantity of exercise and immunocytes, in mice. Twenty six-weeks old inbred C 57 BL/6 Cr mice used for the experiment were divided into two groups : sedentary controls (n=6), and mice taking voluntary exercise (n=14) on running wheels. The period of exercise training was 6 weeks. Beginning at the age of 6 weeks, the daily number of wheel rotations was measured as the quantity of exercise.
　The total number of rotations during the 6 -week period ranged from 377,480 to 587,324, with an average of 492,505±69,685 (mean±S. D.). The daily average numbers of rotations for each week in the training period were 6,802±1,165, 11,668±2,445, 13,262±2,561, 12,696±2,396, 12,333±1,779 and 11,859±1,760 (mean±S.D.).
　The percentage of Thy 1.2⁺, L3T4⁺ and Lyt- 2⁺ cells in blood in the voluntary exercise group was significantly increased compared with the control group. However, the percentage of Igo⁺ cells in the voluntary exercise group was significantly decreased. There was no significant relationship between the quantity of exercise and the percentage of immunocytes in mice. The coefficients of correlation between the quantity of exercise and each type of immunocyte were r=0.1140 (Thy 1.2⁺), r=0.2429 (L3T4⁺), r=0.4278 (Lyt-2⁺) and r=0.1703 (Ig⁺), respectively.

DESCENTE SPORTS SCIENCE Vol.15/THE DESCENTE AND ISHIMOTO MEMORIAL FOUNDATION FOR THE PROMOTION SPORTS SCIENCE