ABSTRACT
The purpose of the present study was to investigate the effects of long-term exercise training on immune function in elderly individuals. This study was conducted on 27 sedentary subjects including 7 males and 20 females aged 66.1±4.2 yrs. (range of 60 to 77 yrs.) who participated in a 12-month exercise program. The subjects attended the exercise program 4.4 ± 1.7 times per month. Peripheral blood samples were taken prior to, and at 5 and 12 months during the exercise training program. Each lymphocyte subset (natural killer: NE, T, cytotoxic T: Tc, helper T: Th, memory-Th and NKT) count in the samples was measured using flow cytometry. Results indicated that NE and Tc cell counts were not significantly altered. Whereas, T and Th cell counts were significantly elevated after 12 months, and memory-Th and NET cell counts were significantly elevated after 5 and 12 months of exercise training. These results suggest that long-term exercise training may be a stimu lus to increase and or maintain immune function in elderly individuals.