Habitual exercise did not affect the balance of type 1 and type 2 cytokines in elderly people

The purpose of this study was to test the hypothesis that regular exercise training in elderly people affects the type 1/type 2 balance. Nine elderly women who train by walking (mean±S.E.M., age 63±1 years, VO ₂ peak 32.2±1.0 ml kg^-1 min^-1), 12 age-matched untrained women (63±1 years, 27.8±0.9 ml kg ^-1 min^-1), and nine young untrained women (26±1 years, 37.8±1.3 ml kg^-1 min^-1) participated in the study. We measured interferon γ (IFN-γ), IL-2, and IL-4 in CD4+ and CD8+ T cells, to compare type 1 and type 2 T cells. The number of CD4+ cells expressing intracellular IFN-γ (CD4+/IFN-γ cell) significantly higher in the elderly trained than in the young (P<0.01). The number of CD8+/IL-2 cells was significantly higher in the elderly trained than in the elderly untrained (P<0.05). The number of CD8+/IL-4 cells was significantly higher in the young than in the elderly untrained (P<0.01). No significant differences were apparent in the IFN-γ/IL-4 ratio within CD4+ and CD8+ cells from the three groups. These results might indicate that the effect of age on the balance of type 1/type 2 T cells was stronger than the effect of physical training.