The effects of vigorous physical exercise on the immune system

• Main Author: Mahan, Michael P.
• Other Authors: Young, M. Rita
• Format: Others
• Published: 2011
• Subjects: Exercise > Physiological aspects.; Immune system.; Stress (Physiology)
• Online Access: http://cardinalscholar.bsu.edu/handle/handle/177950; http://liblink.bsu.edu/uhtbin/catkey/488766

The goal of this study was to access the possibility that a vigorous physical regimen is suppressive to the immune system and that conditioning to the exercise minimizes the immune suppression. The following groups of fifteen rats each were used: (i) control rats. (ii) rats exposed to one bout of swimming for two to three hours (exercise-stressed), and (iii) rats which were conditioned to the exercise by swimming two hours daily for two months (exercise-conditioned).FINDINGS1. Exercise-stressed rats were immune suppressed as compared to control rats. In contrast, exercise-conditioned rats were only slightly immune suppressed.2. The immune reactivity of spleen cells from exercise-stressed rats and from exercise-conditioned rats was restored by the addition of indomethacin, a prostaglandin synthesis inhibitor.3. Exercise-stressed rat spleen cells were more sensitive to the immune suppressive effectsPGE than were the control or excercise-conditioned rat spleen cells.4. The nonadherent spleen cells from both exercise-stressed and exercise-conditioned rats were immune suppressive as compared to control rat nonadherent spleen cells. However, immune stimulatory activity was prominent in the nonadherent spleen cells from the excercise-conditioned rats. Immune stimulatory activity was negligible in the adherent spleen cell fractions from exercise-stressed rats.CONCLUSIONSThe results of this study showed that, extreme physical exercise was immune suppressive while conditioning to the exercise minimized the suppression.The immune suppression in the exercise-stressed rats resulted from an increased sensitivity to the immunosuppressive effects of PGE and from immune suppressor activity of nonadherent lymphoid cells. The minimal extent of immune suppression in the exercise-conditioned rats resulted from a reduced sensitivity to immune suppression by PGE and from immune stimulatory activity of adherent macrophages.