Post-exercise Dietary Protein Strategies

Study Description

Go to 

Study Description Study Design Arms and Interventions Outcome Measures Eligibility Criteria Contacts and Locations More Information

Brief Summary:

Protein ingestion increases the rate at which the body builds new proteins in skeletal muscle (muscle protein synthesis. This study is designed to examine how the pattern of feeding affects muscle protein synthesis following resistance exercise. There is reason to believe that the large rapid increase in blood amino acid concentrations that accompanies the ingestion of a bolus of protein is important to increasing muscle protein synthesis. Thus, we hypothesize that the consumption a bolus of protein will elevate muscle protein synthesis to a greater extent than the consumption of an equivalent amount of protein that is consumed in small divided doses.

Condition or disease	Intervention/treatment	Phase
Optimal Anabolic Nutrition Interventions	Other: whey protein bolus; Other: whey protein pulses	Not Applicable

Detailed Description:

The rapid appearance into the blood of essential amino acids, and leucine in particular, may act as an important signal to stimulate muscle protein synthesis after resistance exercise. This may explain why consuming rapidly-absorbed whey protein may have an anabolic edge over slowly-absorbed proteins such as casein. Previous investigations into importance of the rate of absorption to muscle protein synthesis that have used 'fast' and 'slow' proteins have been confounded by differences in amino acid composition. The present study addresses this issue by administering the same protein source, whey, as either a bolus or in small divided 'pulse' doses to achieve divergent amino acid profiles after a bout of resistance exercise.

This study is being conducted in young (18-35) men.

Our outcome measures include: blood amino acid concentrations, rates of myofibrillar protein synthesis, anabolic intracellular signalling markers

Study Design

Go to 

Study Description Study Design Arms and Interventions Outcome Measures Eligibility Criteria Contacts and Locations More Information

Study Type :	Interventional (Clinical Trial)
Actual Enrollment :	8 participants
Allocation:	Randomized
Intervention Model:	Crossover Assignment
Masking:	None (Open Label)
Official Title:	The Effect of the Pattern Post-exercise Aminoacidemia on Myofibrillar Protein Synthesis
Study Start Date :	July 2009
Actual Primary Completion Date :	October 2009
Actual Study Completion Date :	October 2009

Arms and Interventions

Go to 

Study Description Study Design Arms and Interventions Outcome Measures Eligibility Criteria Contacts and Locations More Information

Arm	Intervention/treatment
Experimental: protein feeding; Participants will complete 2 trials in a cross-over fashion in which they will consume whey protein either as a single bolus or as 10 small divided doses	Other: whey protein bolus; single dose of 25 g whey protein Other: whey protein pulses; 10 2.5 g pulses of whey protein

Outcome Measures

Go to 

Study Description Study Design Arms and Interventions Outcome Measures Eligibility Criteria Contacts and Locations More Information

Primary Outcome Measures :

1. Rate of myofibrillar protein synthesis [ Time Frame: 4 months ]
   Rates of myofibrillar protein synthesis will be measured from muscle biopsy samples obtained from subjects participating in the study protocol.

Secondary Outcome Measures :

1. Myocellular protein phosphorylation [ Time Frame: 4 months ]
   Protein phosphorylation of target proteins will be measured from Western blot analysis of muscle biopsy samples.

Eligibility Criteria

Go to 

Study Description Study Design Arms and Interventions Outcome Measures Eligibility Criteria Contacts and Locations More Information

Ages Eligible for Study:	18 Years to 35 Years (Adult)
Sexes Eligible for Study:	Male
Accepts Healthy Volunteers:	Yes

Criteria

Inclusion Criteria:

• Non-obese men (BMI <27) between the age of 18 and 35 yrs.

Exclusion Criteria:

• Type II diabetes or other known diseases
• Use of medication
• Female
• Other ages or BMI than indicated above
• Resistance training > 3X/wk

Contacts and Locations

Go to 

Study Description Study Design Arms and Interventions Outcome Measures Eligibility Criteria Contacts and Locations More Information

Locations

Canada, Ontario
Ivor Wynne Centre A103, McMaster University
Hamilton, Ontario, Canada, L8S 4K1

Sponsors and Collaborators

McMaster University

RMIT University

Australian Institute of Sport

Nestec Ltd.

Investigators

Principal Investigator:	Stuart M Phillips, PhD	McMaster University

More Information

Go to 

Study Description Study Design Arms and Interventions Outcome Measures Eligibility Criteria Contacts and Locations More Information

Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):

West DW, Burd NA, Coffey VG, Baker SK, Burke LM, Hawley JA, Moore DR, Stellingwerff T, Phillips SM. Rapid aminoacidemia enhances myofibrillar protein synthesis and anabolic intramuscular signaling responses after resistance exercise. Am J Clin Nutr. 2011 Sep;94(3):795-803. doi: 10.3945/ajcn.111.013722. Epub 2011 Jul 27.

Responsible Party:	Dr. Stuart Phillips / Professor & Assoc. Chair Graduate Studies, McMaster University
ClinicalTrials.gov Identifier:	NCT01319513 History of Changes
Other Study ID Numbers:	Darwin 1a - Bolus versus Pulse
First Posted:	March 21, 2011
Last Update Posted:	March 21, 2011
Last Verified:	March 2011