Do walking and social support always relate to autonomic nervous system function in later life? Reexamining an age-based moderating model.

Although walking and social support relate to healthy function of the autonomic nervous system (ANS) in later life, it is unclear whether age groups moderate the relationships of walking frequency and social support with ANS function. To address this area of limited research, we conducted a cross-sectional study with 300 older adults to examine these moderating relationships. Results of multiple regression analysis indicated that walking frequency and social support correlated positively with ANS function. The correlation between walking frequency and ANS function was moderated by age groups, but that between social support and ANS function was not. Therefore, increasing frequency of walking and levels of social support should be considered critical elements of healthy ANS function in later life. However, increasing frequency of walking may be ineffective for old-old adults. We recommend that healthcare practitioners guide old-old adults in seeking sources of social support to promote ANS function.