Effects of different prehabilitation programs on the major abdominal surgery population: a systematic review and network meta-analysis

Background Patients undergoing major abdominal surgery experience high rates of postoperative complications, mortality and healthcare utilization. Prehabilitation is intervention to enhance functional capacity before surgery, aimed at improving the patient’s tolerance to upcoming physiologic stress. We performed a network meta-analysis (NMA) to evaluate the relative effects of different prehabilitation programs on improving fitness and surgical outcomes in patients with the major abdominal surgery. Methods We searched PubMed, Embase, Web of Science, Google Scholar, and Cochrane from inception to June 2025. Randomized controlled trials (RCTs) investigating prehabilitation programs for major abdominal surgery related outcomes of peak volume of oxygen uptake (VO 2peak ), 6-min walk test (6MWT), length of stay (LOS), and postoperative complications were included. The frequentist random-effect NMA method was used to pool the results. Results We included 31 studies with 2,467 participants for meta-analysis. High-intensity interval training (HIIT) was the most effective intervention in improving VO 2peak (SUCRA = 73.9%, MD = 2.29, 95% CI: 0.52–4.06), and aerobic exercise was probably the best intervention for increasing 6-min walking distance (SUCRA = 98.0%, MD = 71.67, 95% CI: 17.44–125.90) that achieved the minimal clinical difference. Multimodal interventions may be more advantageous in reducing LOS (SUCRA = 74.7%, MD = –1.50, 95% CI: –3.02 to –0.02), and HIIT was the most promising prehabilitation program in reducing postoperative complications (SUCRA = 98.4%, OR = 0.03, 95% CI: 0.00–0.51). Conclusion Based on limited quality and direct evidence, our preliminary findings showed that HIIT tended to be most effective in enhancing VO 2peak and reducing postoperative complications in patients undergoing major abdominal surgery. Aerobic exercises were more effective in increasing 6-min walking distance, and multimodal interventions were more advantageous in reducing LOS. Treatment strategies should be based on the patient’s condition and comprehensively determined through real-time evaluation and monitoring. Systematic review registration https://www.crd.york.ac.uk/PROSPERO/ , identifer CRD42024545664.