Physical activity paradox and aging: A population-based study on the association of domain-specific physical activity with biological aging.

Objectives: A physical activity paradox is suggested by recent evidence that leisure-time physical activity (LTPA) is beneficial, whereas it may be detrimental to those with high occupational physical activity (OPA) levels. We aimed to investigate the association of domain-specific PA on the age of the whole body and organs (heart, kidneys, and liver).

Study Design: The analysis utilized data from NHANES, a cross-sectional study with 14,168 enrolled adult participants.

Methods: Domain-specific PA (i.e., Leisure, Transportation, and Occupation) was assessed using the Global Physical Activity Questionnaire (GPAQ). Biological age was calculated from circulating biomarkers. To quantify differences in physiological age between participants, biological age acceleration (BAA) was assessed. Linear regression analysis was used to assess the association of domain-specific PA with BAA of the whole body and organs (heart, kidney, and liver).

Results: The multivariate linear model showed that total PA was negatively associated with whole-body BAA (β -0.47, 95 % CI (-0.71, -0.22)). In addition, LTPA was negatively associated with whole-body BAA (β -0.41, 95 % CI (-0.60, -0.21)) and liver BBA (β -1.20, 95 % CI (-2.05, -0.35)). Whereas OPA was positively associated with heart BAA (β 1.69, 95 % CI (1.05, 2.33)), and we found that only participants who performed OPA≥300 min/week were positively associated with heart BAA (β 1.97, 95 % CI (1.27, 2.66)).

Conclusions: LTPA was associated with slower whole-body and live BAA, while high OPA is associated with higher heart BAA. Associations between domain-specific physical activity and biological aging may differ across activity domains.