Overview
- The JAMA Network Open study analyzed 13,423 community-dwelling Taiwanese adults who completed standardized fitness tests in 2015–2016 and were followed for a median of about seven years through December 31, 2022.
- A multidomain composite fitness index produced the steepest gradient in survival with participants in the top 20% showing about a 61% lower adjusted mortality hazard than those in the bottom 20%.
- Tests of balance and agility, lower-body strength, and cardiorespiratory fitness were the strongest individual predictors of lower all-cause mortality, while upper-body strength and flexibility showed weaker links to survival.
- The authors emphasize limits to causal claims because the study is observational, used a single baseline fitness measure, lacked some covariates such as smoking, and may reflect healthier people being more likely to complete tests.
- If replicated, the findings could lead to routine, simple performance tests in clinical visits to refine risk assessment and guide fall-prevention and function-focused interventions, but trials are needed to show that improving these measures cuts mortality.