THE EFFECT OF MODERATE AEROBIC TRAINING ON LYMPHOCYTE-PROLIFERATION

The purpose of this study was to determine the effect of 12 wks of aer obic training on resting lymphocyte number and proliferation, and immu noglobulin and cytokine levels. Eleven college-aged males (training gr oup = EX) performed 30 min of cycling at 75% of VO(2)peak, 3 days/wk w ith VO(2)peak assessment and blood samples taken at 0, 8 and 12 wks. A group of 10 sedentary controls (CT) underwent the same testing protoc ol. Lymphocyte proliferation response to phytohemagglutinin (PHA) and pokeweed mitogen (PWM) was quantified as a stimulation index (SI) base d on the ratio of stimulated versus control cultures, and as total cou nts per min (CPM). Immunoglobulin (Ig) levels (IgG, IgA, and IgM), and lymphocyte counts were also determined. There was a significant incre ase in VO2 in the EX group (41.0+/-1.8 vs.46.3+/-1.4 ml . kg(-1). min( -1) pre and post training, respectively). Training had no effect on th e PHA SI for the EX group (23.9+/-3.3, 27.7+/-4.1, and 26.3+/-4.0 at 0 , 8 and 12 wks, respectively), or the responses of the CT group (28.8/-6.0, 23.9+/-3.1, and 30.6+/-4.3). No changes were observed for the P WM SI. Significant increases were observed in the CPM for both groups. no differences in the Ig or lymphocyte levels were found during the s tudy. These data indicate that 12 wks of moderate endurance training d id not alter resting immune function as determined by mitogen stimulat ed lymphocyte proliferation, total circulating lymphocytes, or Ig leve ls.