|Appears in Collections:||Faculty of Health Sciences and Sport Journal Articles|
|Peer Review Status:||Refereed|
|Title:||Preexercise aminoacidemia and muscle protein synthesis after resistance exercise|
|Author(s):||Burke, Louise M|
Hawley, John A
Ross, Megan L
Moore, Daniel R
Phillips, Stuart M
Slater, Gary R
Garnham, Andrew P
Coffey, Vernon G
|Keywords:||Amino acid delivery|
fast and slow proteins
muscle protein synthesis
Fatigue Case studies
|Citation:||Burke LM, Hawley JA, Ross ML, Moore DR, Phillips SM, Slater GR, Stellingwerff T, Tipton K, Garnham AP & Coffey VG (2012) Preexercise aminoacidemia and muscle protein synthesis after resistance exercise. Medicine and Science in Sports and Exercise, 44 (10), pp. 1968-1977. https://doi.org/10.1249/MSS.0b013e31825d28fa|
|Abstract:||Purpose: We have previously shown that the aminoacidemia caused by the consumption of a rapidly digested protein after resistance exercise enhances muscle protein synthesis (MPS) more than the amino acid (AA) profile associated with a slowly digested protein. Here, we investigated whether differential feeding patterns of a whey protein mixture commencing before exercise affect postexercise intracellular signaling and MPS. Methods: Twelve resistance-trained males performed leg resistance exercise 45 min after commencing each of three volume-matched nutrition protocols: placebo (PLAC, artificially sweetened water), BOLUS (25 g of whey protein + 5 g of leucine dissolved in artificially sweetened water; 1× 500 mL), or PULSE (15× 33-mL aliquots of BOLUS drink every 15 min). Results: The preexercise rise in plasma AA concentration with PULSE was attenuated compared with BOLUS (P less than 0.05); this effect was reversed after exercise, with two-fold greater leucine concentrations in PULSE compared with BOLUS (P less than 0.05). One-hour postexercise, phosphorylation of p70 S6Kthr389 and rpS6ser235/6 was increased above baseline with BOLUS and PULSE, but not PLAC (P less than 0.05); furthermore, PULSE greater than BOLUS (P less than 0.05). MPS throughout 5 h of recovery was higher with protein ingestion compared with PLAC (0.037 ± 0.007), with no differences between BOLUS or PULSE (0.085 ± 0.013 vs. 0.095 ± 0.010%·h-1, respectively, P = 0.56). Conclusions: Manipulation of aminoacidemia before resistance exercise via different patterns of intake of protein altered plasma AA profiles and postexercise intracellular signaling. However, there was no difference in the enhancement of the muscle protein synthetic response after exercise. Protein sources producing a slow AA release, when consumed before resistance exercise in sufficient amounts, are as effective as rapidly digested proteins in promoting postexercise MPS.|
|Rights:||The publisher does not allow this work to be made publicly available in this Repository. Please use the Request a Copy feature at the foot of the Repository record to request a copy directly from the author. You can only request a copy if you wish to use this work for your own research or private study.|
|Tipton_2012_Preexercise_Aminoacidemia.pdf||Fulltext - Published Version||2.23 MB||Adobe PDF||Under Embargo until 3000-01-01 Request a copy|
Note: If any of the files in this item are currently embargoed, you can request a copy directly from the author by clicking the padlock icon above. However, this facility is dependent on the depositor still being contactable at their original email address.
This item is protected by original copyright
Items in the Repository are protected by copyright, with all rights reserved, unless otherwise indicated.
The metadata of the records in the Repository are available under the CC0 public domain dedication: No Rights Reserved https://creativecommons.org/publicdomain/zero/1.0/
If you believe that any material held in STORRE infringes copyright, please contact firstname.lastname@example.org providing details and we will remove the Work from public display in STORRE and investigate your claim.