Effect of exercise interventions on oxygen uptake in healthy older adults: A network meta-analysis of randomized controlled trials

BACKGROUND: Although aerobic training leads to physiological improvements in older adults, as measured by the VO₂ peak, there is no conclusive evidence on which type of physical exercise intervention is most effective in improving the VO₂ peak. Aim To determine the effects of different physical exercise interventions on oxygen consumption in healthy older adults. METHODS: A network meta-analysis (NMA) was conducted. The literature search was performed from inception to October 2025. Randomized controlled trials (RCTs) assessing the effectiveness of exercise programs on oxygen consumption in healthy older adults were included. The risk of bias was assessed via the Cochrane risk of bias tool (RoB 2.0), and the quality of the evidence was evaluated via the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) framework. Pairwise meta-analyses and NMA were conducted to synthesize both direct and indirect evidence. RESULTS: A total of 16 studies were included in the NMA. The greatest improvements in oxygen consumption were observed in the endurance exercise group versus the control group (effect size [ES]: 2.68; 95 % CI: 2.00-3.35), followed by the combined exercise group versus the control group (ES: 2.31; 95 % CI: 1.02-3.60). CONCLUSIONS: Endurance should be considered the most effective exercise to improve oxygen consumption in healthy older adults, followed by combined exercise. Given the importance of the VO₂ peak as a predictor of quality of life and mortality in older adults, it is essential to include its assessment in clinical guidelines and prioritize the most effective physical activity interventions to enhance it. REGISTRATION: The protocol for this review was registered in PROSPERO (CRD420251081461).