Lymphocyte And Granulocyte Apoptosis After Exhaustive And Moderate Resistance Training: 1276: Board #39 May 30 9:30 AM - 11:00 AM

Apoptosis or programmed cell death is a process of fundamental importance for regulation of the immune response. Several reasons suggest that apoptosis is involved in exercise-induced alterations of the immune system such as post-exercise lymphocytopenia.

PURPOSE: To determine the effect of moderate and intensive resistance training on the apoptosis of lymphocytes and granulocytes.

METHODS: 10 healthy male adults performed two resistance training exercise tests. The first was performed at 80% of 1-RM (intensive resistance test = IRT) and the second 1 week later at 60% of 1-RM with the identical number of repetitions (moderate resistance test = MRT). Blood samples were taken before, immediately after, 3 h after and 24 hours after test. Lymphocytes and granulocytes were analyzed for apoptotic and necrotic cells by using FITC-labeled annexin V-antibodies and nuclear propidium iodide uptake, respectively mitochondrial potential was determined by using DIOC6 and activation status was specified.

RESULTS: Leukocyte counts increased significantly 3h after IRT from 5,02±1,14 mio. cells/μl to 9,95±2,04 mio.cells/μl, while proportion of lymphocytes declined. After the MRT leukocyte counts increase from 4,57±0,96 mio.cells/μl to 5,64±0,86 mio.cells/μl. 3h after the IRT, the percentage of apoptotic lymphocytes increased significantly from 16,3±4,2% to 22,3±5,4% accompanied by a decrease of mitochondrial potential whereas the percentage of apoptotic lymphocytes remained unchanged after the MRT. Percentage of apoptotic granulocytes did not change after both resistance tests, while proportion of activated granulocytes declined after the IRT.

CONCLUSION: These results suggest that IRT is followed by a loss of immunological competence by enhanced numbers of apoptotic lymphocytes.