Clinical Trials Logo

Clinical Trial Summary

Recent studies have reported that oxidation of exogenous carbohydrate is reduced under acute hypobaric hypoxic (high altitude; HA) conditions compared to normoxia (sea level; SL) in native lowlanders. However, the mechanisms by which HA suppresses exogenous carbohydrate oxidation are not known. This study will seek to confirm that acute HA exposure decreases exogenous carbohydrate oxidation during steady-state aerobic exercise compared to SL, and explore if the mechanism inhibiting plasma glucose uptake is insulin dependent or independent.


Clinical Trial Description

This randomized crossover study will examine substrate metabolic responses to ingesting supplemental carbohydrate during steady-state aerobic-type exercise at sea level (SL) and following acute (~5 h) exposure to HA (4,300 m) conditions in 10 healthy, recreationally active adults between the ages of 18-39 yrs. Following a 48-hr muscle glycogen normalization period, volunteers will complete 80-min of metabolically-matched, steady-state aerobic exercise on a treadmill, and consume 145 g of glucose (1.8 g·min-1) at SL and HA. Treadmill exercise will be performed at the same absolute workload, with speed and grade being the same at SL and HA to induce the same absolute workload between phases. SL and HA trials will occur in the US Army Research Institute of Environmental Medicine (USARIEM) hypobaric chamber and will be separated by a minimum 7-d washout period between each protocol day. 6-6-[2H2] glucose will be used as a tracer to assess glucose turnover. Indirect calorimetry, breath sampling for 13C/12C expired in CO2, and urine collections will be used to determine carbohydrate, fat, and protein oxidation during exercise at SL and HA. Serial blood draws will be collected during each trial to assess endocrine and circulating substrate responses to exercise, carbohydrate, and hypoxia. Muscle biopsies will be collected before and after steady-state exercise to examine intramuscular glucose transport expression and translocation, glycogen status, and activity enzyme intermediates in aerobic and anaerobic energy metabolism. ;


Study Design


Related Conditions & MeSH terms


NCT number NCT03851744
Study type Interventional
Source United States Army Research Institute of Environmental Medicine
Contact
Status Completed
Phase N/A
Start date November 28, 2018
Completion date September 1, 2020

See also
  Status Clinical Trial Phase
Recruiting NCT04120051 - The SIMBA Project - The Effect of a Prebiotic Supplement on Glucose Metabolism and Gut Microbiota in Obese Adults N/A
Completed NCT01686815 - Cross-Sectional Iloperidone IVGTT
Completed NCT01034293 - Effect of Feeding Frequency on Glucose and Insulin Metabolism and Substrate Partitioning N/A
Active, not recruiting NCT05642052 - Feasibility Study of a Community Pilot Project for the Prevention of Alzheimer's Disease: the KetoHome Study. N/A
Completed NCT05801731 - A Decentralized Study on Dietary Influences on Cognitive Functions N/A
Completed NCT04611945 - Westlake Sailing Cohort
Active, not recruiting NCT04737694 - Ketone Supplements and Substrate Oxidation and Physical Performance N/A
Completed NCT05282641 - Effects of 10-gram Collagen Protein Hydrolysate on Cardiometabolic Health N/A
Completed NCT03648112 - Effects of Beta-glucan From Barley and Oats on Glucose and Lipid Metabolism, and Satiety N/A
Recruiting NCT04851041 - Effects of a Potato-based Food Pattern vs a Rice / Pasta-based Food Pattern on Cardiometabolic Health N/A
Completed NCT05313594 - Digital Twin - Modelling Postprandial Triglyceride and Glucose Responses
Active, not recruiting NCT01390688 - Brain-derived Neurotrophic Factor and Cogntive Function N/A
Recruiting NCT00953966 - Metabolic Changes Induced by Genetically Modified Potatoes N/A
Completed NCT04928872 - Macronutrient Distribution and Plasma Metabolites to Model Meals Composition
Completed NCT02854709 - Effects of Sleep Extension on Glucose Metabolism in Chronically Sleep Deprived Individuals N/A
Completed NCT00227500 - Pravastatin for Hyperlipidaemia in HIV. Phase 4
Recruiting NCT04894526 - Alternating Energy Intake and Blood Fat Content After a Meal N/A
Recruiting NCT04971408 - Impact of Passive Heat on Metabolic, Inflammatory and Vascular Health in Persons With Spinal Cord Injury Early Phase 1
Terminated NCT04234009 - Lifestyle and Brain Vascular Function N/A
Completed NCT01877460 - Sodium Alginate in Chocolate Milk, Satiety and Glycemic Control N/A