The Effect of Resistance Exercise to Augment Long-term Benefits of Intradialytic Oral Nutritional Supplementation in Chronic Hemodialysis Patients

Background: Resistance exercise combined with intradialytic oral nutrition (IDON) supplementation improves net protein balance in the acute setting in chronic hemodialysis patients. We hypothesized that combination of long-term resistance exercise and IDONwould improve markers of muscle mass and strength further compared with IDON alone. Methods: Thirty-two participants (21 male; mean age, 43 +/- 13 years) on chronic hemodialysis were randomly assigned to IDON plus resistance exercise (NS + EX), or IDON (NS) alone for 6 months. IDON consisted of a lactose-free formula consisting of protein, carbohydrate, and fat. Three sets of 12 repetitions of leg-press were completed before each dialysis session in the NS + EX arm. Primary outcome measurement was lean body mass. Muscle strength and other nutritional parameters were measured as secondary outcomes. Results: Of 32 participants, 22 completed the 6-month intervention. There were no statistically significant differences between the study interventions with respect to changes in lean body mass and body weight, when comparing NS + EX to NS. There were also no statistically significant differences in any of the secondary outcomes measured in the study. Body weight (80.3 +/- 6.6 kg, 81.1 +/- 17.5 kg, and 80.9 +/- 18.2 kg at baseline, month 3, and month 6, respectively; P = .02) and 1-repetition maximum (468 +/- 148 lb, 535 +/- 144 lb, and 552 +/- 142 lb, respectively; P = .001) increased statistically significantly during the study for all patients combined. Conclusion: This study did not show further benefits of additional resistance exercise on long-term somatic protein accretion above and beyond nutritional supplementation alone. When both treatments groups were combined, body weight and muscle strength improved during the study. (C) 2011 by the National Kidney Foundation, Inc. All rights reserved.