Impact of physical exercise interventions on functional fitness in older adults.

Introduction: Aging is associated with a progressive decline in functional fitness-the physiological capacity for performing everyday activities safely and independently-which compromises autonomy in older adults. Maintaining functional fitness is crucial for preserving independence and promoting healthy aging. This systematic review synthesized evidence from recent randomized and controlled clinical trials to evaluate the effects of physical exercise on functional fitness in people aged ≥65 years. Methods: A systematic search was conducted in three major databases (MEDLINE, PMC, and PubMed Central Canada) using comprehensive sets of keywords and MeSH terms related to "older adults" and specific exercise modalities (e.g., endurance, strength, resistance training). The search included studies published between 2015 and 2024. After duplicate removal and application of eligibility criteria, 95 studies were included. A meta-analysis was not performed due to substantial methodological heterogeneity among the included studies. Results: The synthesized evidence indicates that most exercise interventions improved functional fitness outcomes in older adults. Multicomponent programs, resistance training, and supervised protocols were particularly effective. Significant benefits were observed in muscular strength (e.g., ~20-40% improvement in 30-second chair stand test), mobility (e.g., ~1.0-2.5-second reduction in Timed Up and Go test time), balance, and gait speed (e.g., ~0.08-0.15 m/s increase). Positive effects on body composition, such as increased lean mass, were also reported. However, effects on cognitive function were inconsistent. Interventions lasting more than 12 weeks and demonstrating high adherence were associated with more favorable outcomes. Discussion: Structured, well-designed exercise programs tailored to the needs and capacities of older adults represent effective, non-pharmacological strategies to enhance functional independence and promote healthy aging. The observed improvements in muscular strength, mobility, balance, and gait speed underscore the value of regular physical activity in mitigating age-related functional decline. However, the heterogeneity of interventions and limitations in the quality appraisal of included studies should be considered when interpreting these findings. Future research should focus on standardizing intervention protocols and exploring long-term adherence and sustainability of exercise programs in older populations.