Effect of Branched-Chain Amino Acid-enriched nutritional supplement after exercise on skeletal muscle mass in patients undergoing surgery for gastrointestinal cancer

To investigate the effects of branched-chain amino acid (BCAA)-enriched nutritional supplementation after exercise on skeletal muscle and walking ability in patients undergoing gastrointestinal cancer surgery. Fifty patients with gastric or colorectal cancer scheduled for surgery were enrolled in this single-center, single-blind, randomized controlled study. Patients were randomly assigned to a BCAA-enriched jelly group (test group) or an amino acid-free jelly group (control group). Both groups received perioperative exercise therapy and jelly supplementation immediately after exercise. The primary endpoints were percentage changes in thigh skeletal muscle area from pre-intervention to 9 weeks after discharge and from 2 weeks after surgery to 9 weeks after discharge. Secondary endpoints were changes in isometric knee extension and flexion strength and 6-minute walk distance. One patient withdrew consent; therefore, the full analysis set consisted of 24 patients in the test group and 25 patients in the control group. The percentage changes in quadriceps area from pre-intervention to 9 weeks after discharge were 3.24 ± 6.63% and 2.34 ± 16.59% in the test and control groups, respectively, with no significant difference. From 2 weeks after surgery to 9 weeks after discharge, the changes were 8.40 ± 7.57% and 4.44 ± 12.93%, respectively, with no significant difference. No significant differences were observed in hamstring area, lower-limb strength, or 6-minute walk distance between the two groups. Perioperative exercise therapy combined with BCAA-enriched supplementation did not significantly improve thigh skeletal muscle area, muscle strength, or walking ability after surgery in patients undergoing gastrointestinal cancer surgery compared with amino acid-free supplementation. Further studies with adequate sample sizes and higher BCAA intake are warranted.