The Effect of Aerobic, Resistance, and Combined Exercise Training on Cardiorespiratory Fitness in Healthy People Aged 60 years and Over: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Objective: To evaluate the effects of aerobic, resistance, and combined training on cardiorespiratory fitness in healthy older adults, with a focus on improvements in maximal/peak oxygen uptake (VO2max/peak) and the 6-min walk distance (6-MWD). Methods: A systematic review and meta-analysis were conducted through July 2024, searching six databases: PubMed, CINAHL, Medline, Embase, Web of Science, and Scopus. Analyses were performed using Review Manager 5.3. Results: Fifty-one studies involving 3152 participants met the inclusion criteria. Exercise interventions significantly improved VO2max/peak (standardized mean difference (SMD): 0.51; 95% confidence interval (CI), 0.38 to 0.65; p < .001) and 6-MWD (MD: 36.18 m; 95% CI, 26.52 to 45.84; p < .001) compared to control groups. Subgroup analyses showed consistent benefits across aerobic, resistance, and combined training modalities. Significant improvements were also observed across both medium-term (<= 24 weeks) and long-term (>24 weeks) interventions, and in both male and female participants. Conclusion: Structured exercise interventions, regardless of type, are effective for improving cardiorespiratory fitness in older adults. The consistency of these effects across modalities, durations, and sexes underscores the adaptability and value of exercise as a central component of healthy aging strategies. Future research should aim to standardize intervention protocols and extend follow-up periods to clarify long-term outcomes and inform clinical guidelines.