Ingesting glucose during resistance training blunt accumulation of protein expression MuRF1 in vastus lateralis in healthy trained adults..

Purpose: The purpose of this study was to investigate the effect of ingesting liquid glucose during resistance exercise on protein expression of muscle RING finger 1 (MuRF1) on healthy trained adults after 5 training sessions. Method: Thirteen healthy trained participants performed six sessions of heavy-load resistance training with ingestion of glucose or placebo in this within subject randomized clinical trial. The subjects concluded a three-week intervention, consistent of familiarization phase the first week, and two weeks of resistance exercise. The participants legs were randomized in either glucose (GLU) or placebo (PLA), ingested during or after training session. Blood samples and biopsies were taken before and after intervention. The outcome measures were protein expression on MuRF1, nutrition status, muscle strength, training volume and glucose levels in blood. All data is analyzed in R Studio. Results: Intake of glucose during resistance training led to a 26% [-0.4, -0.6] lower accumulation of protein expression MuRF1 in GLU compared to PLA (48% [0.03, 0.07] increase in post). The intervention led to an increase on total volume (PLA: 19% [0.1, 0.25], GLU: 18% [0.08, 0.24]. There was a time effect on isometric test (PLA: 8% [0.007, 0.16], GLU: 4% [-0.03, 0.12] on test 2, isokinetic 60sek (PLA: -18% [-0.25, -0.10], GLU: 9% [-0.16, -0.01] with significant difference between condition (p=0.03), and isokinetic 240sek (PLA -7% [-0.14, -0.01], GLU -5.5% [-0.1, 0.009]) on test 3. There was no difference between condition on restitution effect on isometric and isokinetic tests, but a time effect on isokinetic 60sek after 23 hours training session (p=0.02) Conclusion: Ingesting glucose supplement during resistance training decreases protein content of MuRF1 in skeletal muscl