Dose-Response Relationship Between Physical Activity and Intrinsic Capacity Decline Among Hospitalised Older Patients.

OBJECTIVE

Intrinsic capacity (IC) serves as the foundation for functional performance in older adults, and its decline exerts a significant negative impact on their overall health status. However, the dose-response relationship between physical activity (PA) and IC decline is unclear. The objective of this study was to examine the dose-response relationship between PA and IC decline in hospitalised older adults.

METHODS

This cross-sectional study was conducted from August 2024 to July 2025, with hospitalised older patients recruited from three tertiary hospitals in Gansu Province, China. Data were collected using a general information questionnaire, the IC Assessment Scale and the International Physical Activity Questionnaire-Short Form (IPAQ-SF). Binary logistic regression and restricted cubic spline (RCS) models were used to explore the association between PA and IC decline, adjusting for potential confounders.

RESULTS

The final analyses included a total of 534 hospitalised older patients. Using the low PA group as the reference, the moderate PA group was associated with a 66% lower likelihood of IC decline (OR = 0.34, 95% CI: 0.23-0.50), and the high PA group was associated with a 74% lower likelihood (OR = 0.26, 95% CI: 0.14-0.49). In the RCS analysis, a J-shaped nonlinear association was observed between PA levels and IC decline. Subgroup analyses by sex indicated that sex may serve as a potential moderator in the association between PA and IC decline.

CONCLUSIONS

This study revealed a J-shaped nonlinear association between PA and the likelihood of IC decline, with moderately higher PA levels associated with a lower likelihood of IC decline.