The effects of maltodextrin and protein supplementation on serum metabolites in exercising competitive weight-pulling dogs

Abstract

Post-exercise carbohydrate repletion of skeletal muscle glycogen utilising maltodextrin, with or without highly digestible protein, can improve performance in humans which has been extrapolated to dogs. There is limited metabolic evidence regarding substrate utilisation during exercise with and without supplementation other than serum hormone status and serum amino acid responses. The objectives of this study were 2-fold; (1) to examine the metabolomic changes associated with a weight-pulling exercise; and (2) to examine the effects of maltodextrin/protein supplementation on serum metabolomics during recovery. Serum was collected from 12 dogs (6 control and 6 treatment) at different time points (pre-exercise, 0 min post-exercise, 30 min post, 3 h post) and liquid chromatography-mass spectrometry (LC-MS) was performed identifying 242 metabolites. A two-way analysis of variance for time and treatment with false discovery rate correction was performed using MetaboAnalyst 3.0. There were 9 metabolites found to be significantly increased or decreased immediately after exercise from baseline representing primarily citric acid cycle metabolites. Treatment differences at 30 min post-exercise showed increases in 8 metabolites including amino acids and carbohydrate intermediates with supplementation. Thirty-seven metabolites were significantly different at 3 h post-exercise, with most metabolites being related to amino acid increases, as well as decreases in fatty acid metabolites with supplementation. Definite alterations in metabolites suggesting that post-exercise supplementation with maltodextrin and protein supports glucose metabolism and alters fatty acid metabolism or clearance during recovery from a weight-pulling exercise.