NCT03250234

Carbohydrate Availability and microRNA Expression

Influence of Carbohydrate Availability on Skeletal Muscle and Circulating microRNA Expression

• Status: Completed
• Phase: N/A
• Study type: Interventional
• Enrollment: 12 (actual)
• Sponsor: United States Army Research Institute of Environmental Medicine · Federal
• Sex: All
• Age: 18 Years – 39 Years
• Healthy volunteers: Accepted

Summary

This investigation will examine the impact of skeletal muscle glycogen stores on skeletal muscle and circulating microRNA expression and exogenous carbohydrate oxidation. Primary Objective Determine the influence of carbohydrate availability (e.g., glycogen depletion and repletion) on skeletal muscle microRNA expression, and if changes in circulating microRNA are reflective of changes in skeletal muscle microRNA. Secondary Objective Determine how initiation of exercise with adequate or low glycogen stores effects exogenous carbohydrate efficiency.

Detailed description

Twelve, normal weight, healthy, physically active men and women will complete a glycogen depletion protocol, cycling at various intensities until failure. Participants will then consume a carbohydrate (CHO: 1 g/kg/hr) or an energy free control (CON) beverage matched for taste and color during the first 3-hr post glycogen depletion. For the remainder of the day participants will consume a diet designed to adequately (6.0 g CHO/kg/d) or inadequately (1.2 g CHO/kg/d) replenish glycogen stores. The following day participants will to complete 80-min of steady-state (\~60% VO2peak) cycle ergometry consuming carbohydrate at a rate of 1.8 g/min enriched with a stable isotope of carbon to determine exogenous carbohydrate efficiency when glycogen stores are low or adequate at the onset of exercise. Following a minimum 7-d washout period volunteers will return to the laboratory to complete the second arm of the investigation. To ensure glycogen stores are similar between volunteers on testing day, 48-hrs prior to testing all volunteers will complete a glycogen depletion protocol and then consume a diet providing 6.0 g/kg/d carbohydrate to replenish glycogen stores.

Conditions

• Glycogen Depletion

Interventions

Type	Name	Description
OTHER	Adequate Carbohydrate	During the 3-hr recovery period after glycogen depletion participants will consume a carbohydrate (1 g/kg/hr) beverage For the day participants will consume a diet of 6.0 g/kg/d carbohydrate following glycogen depletion
OTHER	Low Carbohydrate	During the 3-hr recovery period after glycogen depletion participants will consume a nutrient free beverage. For the day participants will consume a diet of 1.2 g/kg/d carbohydrate following glycogen depletion

Timeline

• Start date: 2017-08-01
• Primary completion: 2018-05-03
• Completion: 2018-05-03
• First posted: 2017-08-15
• Last updated: 2021-09-02
• Results posted: 2021-09-02

Locations

1 site across 1 country: United States