Background: The purpose of this study was to determine the effect of moderate physical activity/fitness on the immune response to a defined antigen, in particular, the hemagglutinin-inhibition response to the H1 (A/Texas/36/91) and H3 (A/Johannesburg/33/94) components of the 1995-96 Influenza virus vaccine.
Methods: Sixty-seven volunteers 18-30 years of age (mean 21.1 + 2.3) participated in the study. Physical activity was assessed using the Stanford 7-Day Recall Questionnaire, physical fitness (VO2max) was predicted based on graded submaximal cycle ergometry. Participants were divided into six groups (lower-active/fit, moderate active/fit, and higher active/fit), based on their scores on the 7-Day Recall Questionnaire or predicted VO2max, respectively. Plasma samples were collected prior to, one, two, four, and six weeks post vaccination. A total of four separate repeated measures ANOVA were utilized to evaluate the effect of physical fitness and physical activity on the immune response to the H1 and H3 components of the vaccine.
Results: As expected, for both antigens, titers significantly increased after vaccination, with the highest titers found on week four (H1) and week six (H3), respectively. However, for both antigens, there was no difference between groups and no significant interaction.
Conclusions: The results of this study showed no significant effect of physical fitness or physical activity on the production of specific antibody in the range of physical fitness and physical activity found within this group of college students.