Comparison of balance, functional capacity, and quality of life between older adults with lower and higher levels of physical activity

The primary objective was to compare health outcomes (balance, functional capacity, lower extremity strength, fear of falling, sleep quality, and quality of life) between older adults with higher and lower levels of physical activity. A secondary objective was to explore whether these health-related factors mediated the association between physical activity level and quality of life. A comparative cross-sectional study involved 88 older adults with higher levels of physical activity (higher-PA group) and 88 with lower levels of physical activity (lower-PA group), who underwent mobility tests including the Timed Up and Go Test (TUGT), 2-Minute Walk Test (2MWT), and 10-Meter Walk Test (10MWT); balance and strength assessments such as the Modified Clinical Test of Sensory Interaction in Balance (mCTSIB) and Five-Time Sit-to-Stand Test (5xSTST); and completed self-reported questionnaires including the Fall Efficacy Scale-International (FES-I), Pittsburgh Sleep Quality Index (PSQI), and World Health Organization Quality of Life - Brief (WHOQOL-BREF) Primary analyses compared outcomes between groups with lower and higher levels of physical activity. Mediation analysis was performed to explore indirect effects of balance, fear of falling, lower extremity strength, and sleep quality on the relationship between PA level and Quality of Life (QoL). A total of 176 participants with a mean ± SD age of 65.90 ± 3.84 years and a mean BMI of 23.08 ± 1.43 kg/m² were included. Higher-PA group demonstrated significantly better performance on TUGT, 2MWT, and 10MWT than the lower-PA group, with the younger higher-PA group showing greater 2MWT scores. They demonstrated significantly better mCTSIB, FES-I, and PSQI scores than the lower-PA group. Participants with higher levels of physical activity showed significantly lower FES-I and 10MWT scores compared to those with lower levels. Additionally, mCTSIB scores were significantly influenced by age, income, and occupation, with higher physical activity levels associated with higher mCTSIB scores. Higher-PA group reported significantly better physical and psychological health and environmental and social relationships in QoL domains. Furthermore, adequate sleep duration was significantly associated with improved sleep quality. Parallel mediation analyses revealed that in the physical health domain, all mediators showed significant partial mediation, with the strongest indirect effect via 10MWT (β = 1.116, p = .003). In the psychological domain, PSQI emerged as the most prominent mediator (β = 1.061, p = .001). For the social relationship domain, 2MWT demonstrated the strongest mediation effect (β = 0.546, p = .006). In the environmental health domain, only PSQI (β = 0.475, p = .002) and FES-I (β = 0.239, p = .047) showed significant partial mediation. While controlling for sociodemographic characteristics in the models, all domains showed significant total effects, with partial mediation observed through psychosocial and physical performance variables; however, none of the indirect effects reached statistical significance. Older adults engaging in higher levels of physical activity demonstrated markedly better mobility, balance, and overall QoL compared to their less active counterpart. Physical activity positively influenced all domains of QoL through multiple functional pathways, with significant partial mediation observed via mobility, balance, sleep quality, and fear of falling, most notably within the physical and psychological domains. However, after adjusting for key sociodemographic covariates, the indirect effects were no longer statistically significant. These results highlight the critical role of functional capacities in translating physical activity into improved well-being among older adults.