Mechanisms of B-lymphocyte suppression induced by acute physical exercise.

Blood mononuclear cells from 20 healthy untrained volunteers were isolated before, during, 2 hr and 24 hr after bicycle exercise at 80 % of VO 2 max for 1 hr. A reverse plaque forming cell assay was used to investigate B-lymphocyte function. Stimulation with pokeweed mitogen, recombinant interleukin 2 and Epstein-Barr virus resulted in significant decreases in numbers of IgG-, IgM- and IgA-secreting blood cells during as well as 2 hr after exercise, with reversal to pre-exercise values 24 hr later