EXERCISE TRAINING IMPROVES THE IMMUNE RESPONSE TO INFLUENZA VACCINE IN OLDER ADULTS

Abstract

PURPOSE The purpose of this study was to determine the effect of moderate exercise training on the immune response to influenza vaccine in adults over age 65. METHODS Adults were randomly assigned to either an exercise (EX) (n=14) or a control (CON) (n=13) group. Subjects received the 2000–2001 influenza vaccine in fall, 2000. Beginning 4 weeks post-vaccination, EX subjects exercised 3 days per wk, 25–30 min per day at 55–75% max HRR for 10 months, whereas control subjects were instructed not to change their physical activity habits. In fall, 2001, after the exercise intervention, subjects were immunized with the 2001–2002 influenza vaccine. Antibody titer to the vaccine was evaluated by hemagglutination inhibition (HI) and cytotoxic T lymphocyte function against influenza virus was determined by granzyme B activity. RESULTS There was no difference between EX and CON with respect to antibody titer and cytotoxic T cell function prior exercise training. However, after the 10-month exercise intervention, EX had a significantly greater increase in antibody titer at 4 weeks and 3 month post-vaccination compared to CON. Cytotoxic T lymphocyte function was also greater in EX than CON. CONCLUSION Moderate exercise improves the immune response to influenza immunization in older adults. In addition, if influenza infection does occur, EX subjects may have greater ability to clear the influenza infection than CON, suggested by the increase in cytotoxic T lymphocyte function.