The anabolis potential of dietary protein intake on skeletal muscle is prolonged by prior light-load exercise

TY - JOUR

T1 - The anabolis potential of dietary protein intake on skeletal muscle is prolonged by prior light-load exercise

AU - Bechshøft, Rasmus

AU - Dideriksen, K J

AU - Reitelseder, Søren

AU - Scheike, Thomas

AU - Kjær, Michael

AU - Holm, Lars

PY - 2013/4

Y1 - 2013/4

N2 - Background & aims: Hyperaminoacidemia stimulates myofibrillar fractional synthesis rate (myoFSR) transiently in resting skeletal muscle. We investigated whether light-load resistance exercise can extent this responsiveness. Methods: Ten healthy males exercised one leg with a light-load resistance-like exercise at 16% of 1 repetition maximum and received oral protein boluses every hour for a 10-h period. Their myoFSR was determined by [1-13C]-leucine incorporation. Muscle biopsies were obtained from the resting (REST) and exercised (EXC) muscles every 2.5-h in the protein-fed period. Results: Protein feeding significantly elevated plasma leucine and essential amino acids by an average of 39 ± 9% (mean ± SEM) and 20 ± 4%, respectively, compared to the basal concentrations: 197 ± 12 μmol L-1 and 854 ± 35 μmol L-1, respectively. The myoFSR was similar in EXC and REST muscles in the first 8 h (all time intervals p > 0.05). After 8 h the myoFSR dropped in the REST muscle to 0.041 ± 0.005%·h-1, which was 65 ± 5% of the rate in EXC leg at the same time point (0.062 ± 0.004%·h-1) and 80 ± 14% of the level in REST leg from 0.5 to 8 h (0.056 ± 0.005%·h-1) (interaction p < 0.05). Conclusions: Compared to rest, light-load exercise prolonged the stimulatory effect of dietary protein on muscle biosynthesis providing perspectives for a muscle restorative effect in clinical settings where strenuous activity is intolerable.

AB - Background & aims: Hyperaminoacidemia stimulates myofibrillar fractional synthesis rate (myoFSR) transiently in resting skeletal muscle. We investigated whether light-load resistance exercise can extent this responsiveness. Methods: Ten healthy males exercised one leg with a light-load resistance-like exercise at 16% of 1 repetition maximum and received oral protein boluses every hour for a 10-h period. Their myoFSR was determined by [1-13C]-leucine incorporation. Muscle biopsies were obtained from the resting (REST) and exercised (EXC) muscles every 2.5-h in the protein-fed period. Results: Protein feeding significantly elevated plasma leucine and essential amino acids by an average of 39 ± 9% (mean ± SEM) and 20 ± 4%, respectively, compared to the basal concentrations: 197 ± 12 μmol L-1 and 854 ± 35 μmol L-1, respectively. The myoFSR was similar in EXC and REST muscles in the first 8 h (all time intervals p > 0.05). After 8 h the myoFSR dropped in the REST muscle to 0.041 ± 0.005%·h-1, which was 65 ± 5% of the rate in EXC leg at the same time point (0.062 ± 0.004%·h-1) and 80 ± 14% of the level in REST leg from 0.5 to 8 h (0.056 ± 0.005%·h-1) (interaction p < 0.05). Conclusions: Compared to rest, light-load exercise prolonged the stimulatory effect of dietary protein on muscle biosynthesis providing perspectives for a muscle restorative effect in clinical settings where strenuous activity is intolerable.

U2 - 10.1016/j.clnu.2012.06.015

DO - 10.1016/j.clnu.2012.06.015

M3 - Journal article

C2 - 22867749

SN - 0261-5614

VL - 32

SP - 236

EP - 244

JO - Clinical Nutrition

JF - Clinical Nutrition

IS - 2

ER -