Muscle Protein Synthesis After Whole Egg vs. Egg White Consumption
Condition: Hypertrophy
MeSH terms: Hypertrophy
Study type: Interventional

Summary: 
      In crossover trials, ten (N=10) young men (18-35 y) will receive stable isotope tracer
      infusions and perform a single bout of resistance exercise. Immediately after resistance
      exercise, participants will ingest stable isotope labeled whole eggs (18 g protein, 17 g fat)
      or egg whites (18 g protein, 0 g fat) cooked in scrambled form. Repeated blood and muscle
      biopsies will be collected to determine whole body amino acid kinetics, muscle amino acid
      transporters, anabolic signaling and myofibrillar protein synthesis rates during the trials.
    

Detailed description: 
      On both infusion trials, participants will report to the laboratory at 0700 h after an
      overnight fast. Upon arrival to the lab, a baseline breath sample will be collected for
      determination of 13CO2 enrichment by isotope ratio mass spectrometry. A Teflon catheter will
      be inserted into an antecubital vein for baseline blood sample collection (t=-210 min) and
      then participants will receive priming doses of NaH13CO2 (2.35 µmol·kg-1), L-[1-13C]leucine
      (7.6 µmol·kg-1), and L-[ring-2H5]phenylalanine (2.0 µmol·kg-1). Subsequently, a continuous
      intravenous infusion of L-[1-13C]leucine (0.10 µmol·kg-1·min-1) and L-[ring-2H5]phenylalanine
      (0.05 µmol·kg-1·min-1) will be initiated (t=-210 min) and maintained over the infusion
      trials. A second Teflon catheter willinserted into a heated dorsal hand vein for repeated
      arterialized blood sampling and remained patent by a 0.9% saline drip. Breath samples and
      arterialized blood samples and will be collected every 30 or 60 min during the
      postabsorptive- and postprandial states. In the post-absorptive state of infusion trial 1,
      muscle biopsies will be collected at t=-150 and -30 min of infusion to determine basal-state
      myofibrillar protein synthesis rates, relative skeletal muscle amino acid transporter
      content, and anabolic-related signaling. In the subsequent cross-over trial only 1 muscle
      biopsy will be collected at t=-30 for Western blot analysis and postabsorptive myofibrillar
      protein-bound tracer enrichment. After collection of the resting muscle biopsy at t=-30 for
      both trials, the participants will perform resistance exercise that consists of 4 sets of 10
      repetitions at 80% of 10-RM for both leg press and leg extension exercise.

      Immediately after completion of the exercise bout, participants will consume 3 whole eggs or
      an equivalent amount of protein from egg whites (t=0 min). Completion of the meal will mark
      the start of the postprandial phase (t=0 min) and additional muscle biopsies will be
      collected at t=120 and 300 min.
    

Intervention name(s): Resistance Exercise; Whole Eggs; Egg Whites
Intervention type(s): Behavioral; Other; Other
Intervention description(s): Participants will perform leg extension and leg press immediately prior to ingestion of whole eggs or egg whites; Participants will ingestion whole eggs immediately after resistance exercise; Participants will ingestion whole eggs immediately after resistance exercise
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: Single (Participant)
Primary purpose: Basic Science