| LÓPEZ-RODRÍGUEZ-ARIAS， 2021［11］ | Adults， elective surgery for colon or rectal neoplasm | 10/10 | A 30-d trimodal prehabilitation program with recommendations on physical exercise， nutritional supplementation， and relaxation exercises to be performed at home before surgery and the first 30 d after hospital discharge | Standard care | 12 weeks postoper-ative | ①②⑥ |
| BARBERAN-GARCIA， 2018［12］ | Adults， elective major abdominal surgery with high risk | 62/63 | A personalized prehabilitation program based on their health conditions and social circumstances which encompassed 3 major steps： motivational interview to assess the patients′ adherence profile and to codesign the characteristics of the physical activity program with the patient； personalized program to promote daily physical activity； supervised high-intensity endurance exercise training program | Standard care | Before discharge | ①②③ ④⑤⑥ |
| BOUSQUET-DION， 2018［13］ | Adults， elective surgery for colon or rectal neoplasm | 37/26 | A 4-week multi-modal home-based exercise program with once-weekly supervision consisted of exercise intervention， nutritional intervention and anxiety-reduction strategies | Standard care | 8 weeks postoper-ative | ①②③ ④⑥⑦ |
| OMMUNDSEN， 2018［14］ | >65 years， elective colorectal cancer surgery and fulfilling predefined criteria for frailty | 53/63 | A 3-week pragmatic tailored intervention based on the results of the geriatric assessment | Standard care | 3 months postoper-ative | ①②⑤ ⑥ |
| BURDEN， 2017［15］ | Adults， elective colorectal cancer surgery with preoperative weight loss>1 kg per 3‒6 months | 55/45 | Oral supplementation （10.1 KJ， 0.096 g of protein per mL） at a dose of 250 mL daily for a minimum of 5 d before the operation | Bottled water | 30 days postoper-ative | ①②⑥ ⑦ |
| GILLIS， 2016［16］ | Adults， elective surgery for colon or rectal neoplasm | 22/21 | A whey protein supplement was provided in a quantity that matched the patient′s need according to the estimated deficit in dietary protein intake for approximately 4 weeks leading up to the surgery | Placebo | 4 weeks postoper-ative | ③⑥ |
| GILLIS， 2014［17］ | Adults， elective surgery for colon or rectal neoplasm | 38/39 | A 4-week trimodal prehabilitation program at home included exercise intervention， nutrition intervention， and coping strategies to reduce anxiety | Standard care | 8 weeks postoper-ative | ①③④ ⑥ |
| FUJITANI， 2012［18］ | ≤80 years， elective total gastrectomy， body weight loss of 10 percent or less within 6 months before entry | 127/117 | Preoperative oral supplementation of 1 000 mL/d in the form of an immunonutrient-enriched enteral feed added to normal diet for 5 d consecutively before the surgery | Normal diet | Before discharge | ①②⑥ |
| BURDEN， 2011［19］ | Adults， elective surgery for colon or rectal neoplasm | 54/62 | Oral supplementary drink of 400 mL daily， and dietary advice for 10 d before the operation | Dietary advice only | Before discharge | ①②⑥ |
| SMEDLEY， 2004［20］ | Adults， elective moderate to severe lower gastrointestinal surgery | 48/50 | Oral nutritional supplement in small， frequent quantities between meals for 7 d before the operation， the volume consumed was recorded | Normal diet | Before discharge | ①②⑥ ⑦ |
| GIANOTTI， 2002［21］ | Adults， major elective surgery for malignancy of the gastrointestinal tract | 102/102 | Oral nutritional supplement （1 000 mL/d） of a formula enriched with arginine， ω-3 fatty acids， and RNA for 5 d before the operation | Standard care | 30 d after discharge | ①②⑤ ⑥ |
| BRAGA， 2002［22］ | Adults， elective surgery for gastroin-testinal neoplasm， body weight loss of 10% or more within 6 months before entry | 50/50 | Oral nutritional supplement （1 000 mL/d） added to normal diet for 7 d consecutively before the surgery | Normal diet | 30 d after discharge | ①②⑤ ⑥ |
| KABATA， 2015［23］ | Adults， elective， radical gastroin-testinal and abdominal cancer surgery | 54/48 | Oral nutritional supplement （400 mL/d） added to normal diet for 14 d consecutively before the surgery | Normal diet | 30 d postoper-ative | ①⑤⑥ |
| BARKER， 2013［24］ | Adults， elective upper and lower gastrointestinal surgery | 46/49 | Three packs of 237 mL of oral nutritional supplement per day for 5 d before the surgery | Standard care | 30 d postoper-ative | ①②⑤ ⑥ |
| BERKEL， 2022［25］ | ≥60 years， elective surgery for colon or rectal neoplasm | 28/29 | A personalized 3-week （3 sessions per week， 9 sessions in total） supervised exercise program | Standard care | 90 d postoper-ative | ①②⑥ |
| HUANG， 2014［26］ | Adults， elective， radical gastroin-testinal， cancer surgery | 41/41 | Oral nutritional supplement （25 mL/kg） for 7 d before the surgery | Normal diet | Before discharge | ①②⑥ |