NCT04910724

Effects of Varying Energy Deficits on Protein Turnover at Rest and Carbohydrate Oxidation During Steady-state Exercise

• Status: Completed
• Phase: N/A
• Study type: Interventional
• Enrollment: 30 (actual)
• Sponsor: United States Army Research Institute of Environmental Medicine · Federal
• Sex: All
• Age: 18 Years – 35 Years
• Healthy volunteers: Accepted

Summary

This randomized, parallel study will examine the effects of energy balance and varying magnitudes of energy deficit on 1) the protein kinetic responses to consuming high quality protein and 2) carbohydrate oxidation during steady-state exercise. Healthy adults, representative of active duty military personnel, will complete a 2 d energy balance phase followed by a randomly assigned, 5 d energy deficit phase (n=15 per group; 20%, 40% and 60% energy deficit). At the end of each energy phase the effects of energy balance and energy deficit severity on resting postabsorptive (fasting) and postprandial (after consuming \~34 g protein) muscle protein synthesis (MPS) and whole-body protein synthesis, breakdown, and balance (synthesis - breakdown) will be determined. On the next day, the effects energy balance and energy deficit severity on carbohydrate oxidation during steady-state exercise will be determined. Primary study procedures include anthropometric and body composition measures, resting metabolic rate measures, aerobic exercise, tightly controlled diet and exercise interventions, repeated blood sampling, stable isotope infusion, stable isotope ingestion, and percutaneous muscle biopsies. The following hypotheses will be tested: 1) Δ (postprandial - postabsorptive) MPS and Δ whole-body protein balance at rest will progressively decrease as magnitude of energy deficit increases and 2) exogenous carbohydrate oxidation will be higher and endogenous carbohydrate oxidation will be lower during steady-state exercise as magnitude of energy deficit increases.

Conditions

• Energy Supply; Deficiency, Severe
• Energy Supply; Deficiency
• Stress, Physiological

Interventions

Type	Name	Description
OTHER	Energy Deficit	A combination of individualized exercise performed on a cycle ergometer and individualized dietary prescriptions will be used to achieve energy balance or the assigned energy deficits throughout the controlled feeding and testing periods

Timeline

• Start date: 2022-08-16
• Primary completion: 2024-03-07
• Completion: 2024-03-07
• First posted: 2021-06-02
• Last updated: 2026-01-21

Locations

1 site across 1 country: United States