Physical Effort-Induced Changes in Immune Parameters

Abstract

Physical stress induces changes in immune system parameters; these changes depend on effort schedule and are influenced by customary training. The mechanisms whereby they take place are not fully elucidated: sympathetic activation-mediated mobilization of cells of lymphoid organs, including the spleen, has been suggested

We studied exercise-induced changes (20′ of cycloergometer test conducted up to 804% of maximal expected heart rate) in white blood cells (WBC), lymphocyte subsets, plasma catecholamine and cortisol levels in three groups of subjects: swimmers, untrained controls and splenectomized individuals. Physical exercise induced increase of WBC and significant changes in the percentage of most investigated lymphocyte subsets (NK, CD3⁺, CD4⁺, CD8⁺ and CD4/CD8 ratio), except for DR+ cells. No changes occurred in the percentage of CD14⁺ cells. Norepinephrine (NE) levels increased after effort, while epinephrine (E) and cortisol levels were unchanged. Splenectomized patients displayed similar effort-induced changes in investigated parameters as controls and swimmers

The results support the interactions between physical work and immune response and minimize the role of the spleen in this context

Key Words:

• Physical work
• immune function
• lymphocyte subsets
• sympathetic control
• splenectomy