Skeletal Muscle Protein Synthetic Response to Amino Acid and Peptides

Summary

Skeletal muscle quality is an important determinant of exercise performance and overall health. It is vital for not just movement, but also metabolizing nutrients. Protein from the diet can promote muscle protein synthesis for muscle recovery and growth. More importantly, doing so shifts net protein balance positively (e.g. protein synthesis is greater than protein breakdown) and promotes greater rates of muscle protein turnover. Leucine is an amino acid required to build muscle, but it also acts as a signaling molecule informing the muscle to start protein synthesis. Before reaching skeletal muscle, dietary protein is digested into small peptides and free amino acids. Rate of absorption from the intestine to the blood stream is significantly faster for peptides compared to amino acids. As amino acid availability in the blood is a precursor for muscle protein synthesis, our objective is to determine if the different absorption rates between free amino acid and peptides influence muscle protein synthetic and breakdown rates.

Conditions

• Protein Metabolism

Interventions

BEHAVIORAL

Resistance Exercise

Prior to protein consumption participants will perform an acute bout of resistance exercise. They will warm up with two sets of 10 repetitions at 35-75% working load respectively, then perform four working sets of 10-12 repetitions at 65-70% of 1-RM. 1 min, 30 sec rest periods will be implemented between each set.

BEHAVIORAL

No Resistance Exercise

Participants allocated to this group will not perform exercise prior to the administration of the nutritional intervention. Participants will remain at rest throughout the trial.

DIETARY_SUPPLEMENT

Leucine

Participants will be given 2g of leucine dissolved in 250mL of water. Drink will be consumed immediately after exercise or equivalent time point for non-exercise group.

DIETARY_SUPPLEMENT

Dileucine

Participants will be given 2g of dileucine dissolved in 250mL of water. Drink will be consumed immediately after exercise or equivalent time point for non-exercise group.

Sponsors & Collaborators

• University of Illinois at Urbana-Champaign

  lead OTHER

Principal Investigators

• Nicholas A. Burd, Ph.D. · University of Illinois at Urbana-Champaign

Study Design

Allocation

RANDOMIZED

Purpose

BASIC_SCIENCE

Masking

TRIPLE

Model

CROSSOVER

Eligibility

Min Age

18 Years

Max Age

35 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2019-05-03

Primary Completion

2019-11-20

Completion

2019-11-20

Countries

• United States

Study Locations