Lymphocyte subpopulations and concentrations of soluble CD8 and CD4 antigen after anaerobic training

In 13 middle-aged, moderately trained men (40-60 yr) we investigated the influence of anaerobic training on immunological parameters measured at rest. The 4 week anaerobic training program (two 30-min sessions weight lifting and one interval training per week; lactate levels 4-6 mM and 8-10 mM, respectively), caused a significant increase of the mean arm muscle force by 7% (handgrip test, p < 0.05). Evaluation of lymphocyte subsets was performed by means of three-colour immunofluorescence analysis (FACS). After 4 weeks of training we found a significant reduction of the CD4+ T-cell counts by 15% (p < 0.05) paralleled by a fall of naive cells (CD3+/CD4+/CD45RA+) by 16%, which, however, was statistically not significant. While percentages of CD3+ lymphocytes decreased significantly by 6% (p < 0.001), absolute numbers of CD3+ T-lymphocytes were not detectably affected and also the relative ratio of CD8+ T-cell subsets, i.e. the ratio of suppressor vs cytotoxic T-cells (CD3+/CD8+/CD11b+, CD3+/CD8+/CD11b- respectively) remained unchanged. Likewise the serum concentrations of the soluble CD8 and CD4 antigen (sCD8/sCD4) as determined by sandwich enzyme immunoassays were found to be unaffected. We conclude that 40-60 years old healthy human subjects performing anaerobic training experience on average a significant decrease of circulating CD4+ T-lymphocytes, while other parameters including the activation parameters sCD8 and sCD4 remained unchanged.