Effect of physical activity on the production of specific antibody in response to the 1998-99 influenza virus vaccine in older adults.

AIM: The purpose of this study was to determine the effect of physical activity on the production of specific antibody in response to a defined antigen, in particular, the hemagglutinin-inhibition response to the H3N2 (A/Sidney/05/97) and H1N1 (A/ Beij-ing/262/95) component of the 1998-99 influenza virus vaccine. METHODS: Thirty older adults aged 67 to 91 years (mean 81+/-5) participated in the study. Physical activity was assessed using the Physical Activity Scale for the Elderly (PASE); a log-base 2 increase (fold increase) in titer of a serum over the prebleed for each person was representative of the immune response. Plasma samples were collected prior to, 1, 2, 4, and 6 weeks postinfluenza virus vaccination. A repeated measures ANOVA was used to evaluate the overall immune response to the H3N2 and H1N1 components of the influenza virus vaccine. Pearson correlations were used to determine the relationship between specific antibody production and physical activity. RESULTS: As expected, for both antigens, titers significantly increased after vaccination with the highest titers found six weeks postvaccination. A significant correlation between physical activity and specific antibody production was found for the Sidney component of the vaccine (H3N2) one week post- vaccination (r=0.59; p<0.05). CONCLUSION: The results of the present study indicated a positive relationship between physical activity and the initial immune response to a specific antigenic challenge in the present sample of older adults.

Effects of smoking abstinence on movement regulation.

The effect of smoking abstinence on performance of a reciprocal tapping task was investigated. 6 habitual smokers performed a single-plate and two versions of a two-plate tapping task. Fitts' Law was used to compute an index of difficulty (ID) in bits for the tasks which was 0 bits for the single-plate and 3.32 and 4.17 bits for the two-plate versions of the task. While smoking abstinence had no effect on performance of the single-plate tapping task, it increased movement time on performance of both two-plate task versions. These findings may provide a coherent explanation for the prior findings of nicotine deprivation on psychomotor performance in the literature. This explanation suggests that the effects of nicotine deprivation as incurred through smoking abstinence may be on the central mechanisms regulating information-processing rate for successful movement regulation. Thus nicotine deprivation may not affect performance of simple psychomotor tasks which require minimal information processing but will affect the performance of more complex tasks requiring significantly more information processing for successful movement regulation.