Effects of Protein Quality on Post-exercise Skeletal Muscle and Whole-body Protein Kinetics During Energy Deficit

United States Army Research Institute of Environmental Medicine10 enrolled

Overview

The optimal EAA-containing protein format necessary to maximally stimulate muscle protein synthesis and optimize whole-body net protein balance during caloric deprivation has not been determined. This study will address that gap in knowledge by examining post, whole-body exercise muscle and whole-body protein kinetic responses to ingesting varying EAA-containing protein formats after a 5 day period of negative energy balance. This study will provide the initial evidence to support the development of a recovery-based food product for military combat rations.

Ten resistance-trained adults will complete this \~55-d randomized, cross-over study. Participants will participate in three, non-consecutive 5-d controlled energy deficit periods, each separated by a 14-d washout period (i.e., sufficient time to restore nitrogen and metabolic homeostasis after moderate weight loss). Post-exercise (whole-body exercise model) muscle protein synthesis (MPS) and whole-body protein turnover responses to varying EAA-containing protein formats will be determined the morning after completing the 5-d energy deficit.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

BASIC_SCIENCE

Masking

DOUBLE

Enrollment

Conditions

Whole-body Protein Balance Muscle Protein Synthesis

Interventions

Essential Amino Acid Enriched Whey ProteinDIETARY_SUPPLEMENT

protein powder formulation that includes whey and free-form essential amino acids

Whey ProteinDIETARY_SUPPLEMENT

commercially available whey protein isolate

Military Ration EntreeDIETARY_SUPPLEMENT

chili and beans entree; current meal component of the meals ready to eat rations

Eligibility

Sex: ALLMin age: 18 YearsMax age: 35 YearsHealthy volunteers:

Medical Language ↔ Plain English

Inclusion Criteria: * Men and women aged 18 - 35 years * Body mass index \< 30.0 kg/m2 * Healthy without evidence of chronic illness or musculoskeletal injury as determined by the USARIEM Office of Medical Support and Oversight (OMSO) or home duty station medical support * Resistance exercise trained defined by self-report as performing ≥ 2 sessions/wk for previous 6 mo * Refrain from taking any nonsteroidal anti-inflammatory drugs (e.g., aspirin, Advil®, Aleve®, Naprosyn®), or any other aspirin-containing product for 10 days before starting and at least 5 days after completing the study * Willing to refrain from alcohol, smoking any nicotine product (includes e-cigarettes); vaping, chewing tobacco, caffeine, and dietary supplement use throughout the entire study period * Supervisor approval for federal civilian employees and non-HRV active duty military personnel working within the US Army Natick Soldier Systems Center Exclusion Criteria: * Musculoskeletal injuries that compromise exercise capability as determined by the USARIEM or home duty station Office of Medical Support and Oversight (OMSO) * Metabolic or cardiovascular abnormalities, gastrointestinal disorders (e.g., kidney disease, diabetes, cardiovascular disease, etc.) * Abnormal PT/PTT test or problems with blood clotting * History of complications with lidocaine * Present condition of alcoholism, anabolic steroids, or other substance abuse issues * Blood donation within 8-wk of beginning the study * Pregnant, trying to become pregnant, and/or breastfeeding (results of urine pregnancy test or self-report for breastfeeding will be obtained before body composition testing) * Unwillingness or inability to consume study diets or foods provided

Outcomes

Primary Outcomes

How fast participants build skeletal muscle after ingesting varying forms of essential amino acid-containing proteins after exercise

Assessed using stable isotope infusions of phenylalanine.

Time frame: ~4.5 hour measure of muscle protein synthesis

Secondary Outcomes

How well participants suppress the degradation of body proteins while stimulating the growth of new proteins after ingesting varying forms of essential amino acid-containing proteins after exercise.

Assessed using stable isotope infusions of tyrosine.

Time frame: ~4.5 hour measure of whole-body protein balance