EAA + CHO før trening øker ikke proteinsyntese i etterkant av trening.

[Lasse Christoffersen]

Essential amino acid and carbohydrate ingestion prior to resistance exercise does not enhance post-exercise muscle protein synthesis.

Fujita S, Dreyer HC, Drummond MJ, Glynn EL, Volpi E, Rasmussen BB.
University of Tokyo.

Ingestion of an essential amino acid-carbohydrate (EAA+CHO) solution following resistance exercise enhances muscle protein synthesis during post-exercise recovery. It is unclear whether EAA+CHO ingestion prior to resistance exercise can improve direct measures of post-exercise muscle protein synthesis (FSR; fractional synthetic rate). We hypothesized that EAA+CHO ingestion prior to a bout of resistance exercise would prevent the exercise-induced decrease in muscle FSR and would result in an enhanced rate of muscle FSR during post-exercise recovery. We studied 22 young healthy subjects before, during, and for 2 hr following a bout of high-intensity leg resistance exercise. The Fasting control group (N=11) did not ingest nutrients and the EAA+CHO group (N=11) ingested a solution of EAA+CHO 1 hr prior to beginning the exercise bout. Stable isotopic methods were used in combination with muscle biopsies to determine FSR. Immunoblotting procedures were utilized to assess cell signaling proteins associated with the regulation of FSR. We found that muscle FSR increased in the EAA+CHO group immediately following EAA+CHO ingestion (P<0.05), returned to basal values during exercise, and remained unchanged at 1 hr post-exercise. Muscle FSR decreased in the Fasting group during exercise and increased at 1 hr post-exercise (P<0.05). However, the 2 hr post-exercise FSR increased by ~50% in both groups with no differences between groups (P>0.05). Eukaryotic elongation factor 2 phosphorylation was reduced in both groups at 2 hr post-exercise (EAA+CHO: 39+/-7%; Fasting: 47+/-9%; P<0.05). We conclude that EAA+CHO ingestion prior to resistance exercise does not enhance post-exercise FSR as compared to exercise without nutrients. Key words: essential amino acids, resistance exercise, muscle protein synthesis, protein metabolism, leucine.

PMID: 18535123 [PubMed - as supplied by publisher]

[Kengdal]

Har du lest hele? Hvor mye EEA er det snakk om?

[Lasse Christoffersen]

Nei har bare lest abstrakten. Håpet noen kunne komme med litt mer input

[Beefcake]

... and the EAA+CHO group (N=11) ingested a solution of EAA+CHO 1 hr prior to beginning the exercise bout. ...

En time før trening gir ingen ekstra effekt, men rett før gir imidlertid det:

"The present study was designed to determine whether consumption of an oral essential amino acid-carbohydrate supplement (EAC) before exercise results in a greater anabolic response than supplementation after resistance exercise. Six healthy human subjects participated in two trials in random order, PRE (EAC consumed immediately before exercise), and POST (EAC consumed immediately after exercise). A primed, continuous infusion of L-[ring-2H5]phenylalanine, femoral arteriovenous catheterization, and muscle biopsies from the vastus lateralis were used to determine phenylalanine concentrations, enrichments, and net uptake across the leg. Blood and muscle phenylalanine concentrations were increased by ~130% after drink consumption in both trials. Amino acid delivery to the leg was increased during exercise and remained elevated for the 2 h after exercise in both trials. Delivery of amino acids (amino acid concentration times blood flow) was significantly greater in PRE than in POST during the exercise bout and in the 1st h after exercise (P < 0.05). Total net phenylalanine uptake across the leg was greater (P = 0.0002) during PRE (209 ± 42 mg) than during POST (81 ± 19). Phenylalanine disappearance rate, an indicator of muscle protein synthesis from blood amino acids, increased after EAC consumption in both trials. These results indicate that the response of net muscle protein synthesis to consumption of an EAC solution immediately before resistance exercise is greater than that when the solution is consumed after exercise, primarily because of an increase in muscle protein synthesis as a result of increased delivery of amino acids to the leg. "

Tipton & Wolfe et al, Am J Physiol Endocrinol Metab 281: E197-E206, 2001; Timing of amino acid-carbohydrate ingestion alters anabolic response of muscle to resistance exercise.