Supplementary Material for: Safety, compliance, and efficacy of prehabilitation in obese patients with gastric cancer undergoing minimally invasive gastrectomy: A pilot prospective study

Background: Excessive visceral fat area is a risk factor for postoperative complications in gastric cancer patients undergoing minimally invasive gastrectomy. This prospective pilot study aimed to evaluate the safety, compliance, and efficacy of prehabilitation in obese patients with gastric cancer who were scheduled to undergo curative gastrectomy. Methods: Patients with preoperative visceral fat area ≥ 100 cm2 who were scheduled to undergo curative minimally invasive gastrectomy for stages I–III gastric cancer were included. The patients were instructed to walk 10,000 steps per day and consume a low-carbohydrate, high-protein diet without energy restrictions for 1 month before surgery. The primary outcome was the visceral fat area reduction rate, and clinical significance was set at a 10% reduction. Results: Eighteen patients were enrolled in the study, and no adverse events were observed. The mean number of steps per day was 10,572. the mean exercise time greater than or equal to moderate intensity was 42.3 min per day, and 88% of the patients completed the 1-month intervention. Although the skeletal muscle mass was preserved, the visceral fat area reduced by 17% (95% confidence interval: 11%–24%, p = 0.039). Conclusions: Prehabilitation can safely reduce visceral fat area before performing minimally invasive gastrectomy in patients with gastric cancer who are obese.