A meta-analysis of 8 studies in which 442 patients underwent liver, colorectal, gastroesophageal, and general abdominal surgery showed preoperative exercise significantly reduced pulmonary complications as well as in postoperative overall morbidity in exercise group2.
152 patients in which half performed physical fitness training before liver, gall, pancreas, and bile duct surgery, analysis showed that in the exercise group serum albumin rose instead of fall, the muscle to fat ratio improved, 6-minute walking test was better and discharge time was accelerated6.