Optimized Carbohydrate Fueling to Enhance Physical Performance During Energy Deficit

April 26, 2024 updated by: United States Army Research Institute of Environmental Medicine
This randomized crossover study will examine the effects of consuming isocaloric GLU+FRU or GLU alone on rates of exogenous carbohydrate oxidation during aerobic exercise and physical performance (time trial) under energy balance (BAL) and energy deficit (DEF). Baseline data will be collected on volunteer height, weight, body composition, and V̇O2peak. To ensure volunteers are familiar with exercise protocols, they will complete practice sessions of all exercise before the start of data collection. Exercise and diet will be controlled throughout data collection. To start the protocol volunteers will complete a bout of glycogen normalization on a cycle ergometer followed by 48 hours of refeeding at 100% (BAL) or 50% (DEF) of their energy needs. After the 48 hours of refeeding volunteers will return to the laboratory to complete 80 min of steady-state (60 ± 5% V̇O2peak) exercise on a cycle ergometer. Immediately before and during steady-state exercise, volunteers will consume either 80 g of GLU+FRU (53 g glucose + 27 g fructose) or 80 g GLU. Drinks containing corn-derived crystalline fructose (KRYSTAR® 300, Tate and Lyle Sugars, London, UK) and glucose (CERELOSE®, Ingredion, Westchester, IL, USA) will be prepared by unblinded USARIEM staff. Drinks will be enriched with 13C stable isotopes (Cambridge Isotope Laboratory, Andover, MA, USA) to measure exogenous and plasma carbohydrate oxidation during steady-state exercise. After steady-state exercise, physical performance will be assessed using a graded exercise test on a stationary bike. Indirect calorimetry and breath sampling will be used to determine substrate oxidation during steady-state exercise. Serial blood draws will be collected during each trial to assess isotope enrichments, and circulating substrate/hormone responses. Muscle biopsies will be performed before and after steady-state exercise to assess glycogen status, enzyme activity, and molecular regulation of substrate metabolism. There will be a minimum of 7 days between each carbohydrate metabolism study day.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Recruiting

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

Periods of energy deficit (DEF) contribute to declines in physical performance during military operations. During DEF, glucose (GLU) supplementation alone is likely an insufficient intervention to enhance physical performance. The lack of an ergogenic effect with GLU consumption during DEF may result from lower glucose uptake and exogenous glucose oxidation in peripheral tissue. As the current carbohydrate beverage base in Meals, Ready-to-Eat (MRE) is derived solely from GLU, an alternative ration product may be needed to enhance physical performance during DEF. Use of multiple transportable carbohydrates, such as glucose plus fructose (GLU+FRU) may be a more effective ration product, as it has been shown to increase rates of exogenous carbohydrate oxidation and improve physical performance compared to GLU. However, previous studies have only been conducted during energy balance (BAL), and the influence of GLU+FRU on substrate oxidation and physical performance compared to GLU during DEF is currently unknown. This randomized crossover placebo controlled double blinded study will examine the effects of consuming GLU compared to GLU+FRU on substrate oxidation and physical performance during metabolically-matched, steady-state exercise during BAL and DEF. Twelve healthy, recreationally active men and women between the ages of 18-39 yrs will be required to complete this study. To start the protocol volunteers will complete a bout of glycogen normalization cycling followed by 48 hours of refeeding at 100% (BAL) or 50% (DEF) of their energy needs. After the 48 hours refeeding volunteers will return to the laboratory and complete 80 min of steady-state (60 ± 5% VO2peak) cycling. Immediately before and during steady-state exercise, volunteers will consume either 80 g of GLU+FRU (53 g glucose + 27 g fructose) or 80 g GLU. Drinks will be enriched with 13C stable isotopes to measure exogenous carbohydrate oxidation during steady-state exercise. After steady-state exercise, aerobic performance will be assessed. Indirect calorimetry and breath sampling will be used to determine substrate oxidation during steady-state exercise. Serial blood draws will be collected during each trial to assess isotope enrichments, and circulating substrate/hormone responses. Muscle biopsies will be performed before and after steady-state exercise to assess glycogen status, enzyme activity, and molecular regulation of substrate metabolism. Volunteers will complete all four trials (BAL: GLU, DEF: GLU, BAL: GLU+FRU, DEF: GLU+FRU) in a randomized order under controlled laboratory conditions at USARIEM. There will be a minimum of 7 days between each carbohydrate metabolism study day.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Estimated)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
12

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact

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Study Locations

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

  • Adult

Accepts Healthy Volunteers

Yes

Description

Inclusion Criteria:

  • Men and women aged 18 - 39 years
  • 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
  • Routinely participate in aerobic and/or resistance exercise at least 2 days per week
  • Willing to refrain from alcohol, smoking/using any nicotine product (includes e-cigarettes, vaping, chewing tobacco), caffeine, and dietary supplements while consuming the study diet
  • Supervisor approval for federal civilian employees and non-HRV active duty military personnel
  • Females must have normal menstrual cycles between 26-32 days in duration; 5 menstrual cycles within the past 6 months; or on continuous oral or IUD contraception without placebo.

Exclusion Criteria:

  • Musculoskeletal injuries that compromise exercise capability
  • Metabolic or cardiovascular abnormalities, gastrointestinal disorders (e.g., kidney disease, diabetes, cardiovascular disease, etc.), claustrophobia
  • Significantly abnormal blood clotting as determined by OMSO or home duty station medical support
  • Allergy to lidocaine (or similar local anesthetic)
  • Present condition of alcoholism, anabolic steroid use, or other substance abuse issues as determined by OMSO or home duty station medical support
  • Blood donation within 8-wk of beginning the study
  • Pregnant, trying to become pregnant, and/or breastfeeding (results of urine pregnancy test and self-report for breastfeeding will be obtained before body composition testing)
  • Unwilling or unable to consume study diets or foods provided due to personal preference, dietary restrictions, and/or food allergies
  • Unwilling or unable to adhere to study physical restrictions

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Crossover Assignment
  • Masking: Triple

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Active Comparator: Energy Balance: Glucose
Following 48 hours of consuming an energy balance diet, volunteers complete 80 min of steady-state (60 ± 5% V̇O2peak) exercise on a cycle ergometer while consuming 80 g of glucose
Dietary supplement: BAL:GLU
80 g glucose consumed during steady-state exercise following 48 hours of consuming an energy balance diet
Experimental: Energy Balance: Glucose plus Fructose
Following 48 hours of consuming an energy balance diet, volunteers complete 80 min of steady-state (60 ± 5% V̇O2peak) exercise on a cycle ergometer while consuming 53 g of glucose and 27 g of fructose.
Dietary supplement: BAL:GLU+FRU
53 g glucose plus 27 g fructose consumed during steady-state exercise following 48 hours of consuming an energy balance diet
Active Comparator: Energy Deficit: Glucose
Following 48 hours of consuming an energy deficit diet, volunteers complete 80 min of steady-state (60 ± 5% V̇O2peak) exercise on a cycle ergometer while consuming 80 g of glucose
Dietary supplement: DEF:GLU
80 g glucose consumed during steady-state exercise following 48 hours of consuming an energy balance diet
Experimental: Energy Deficit: Glucose plus Fructose
Following 48 hours of consuming an energy deficit diet, volunteers complete 80 min of steady-state (60 ± 5% V̇O2peak) exercise on a cycle ergometer while consuming 53 g of glucose and 27 g of fructose.
Dietary supplement: DEF:GLU+FRU
53 g glucose plus 27 g fructose consumed during steady-state exercise following 48 hours of consuming an energy balance diet

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Exogenous carbohydrate oxidation
Time Frame: 80 minutes
Determine the effects of consuming glucose compared to glucose plus fructose on the rate (g/min) of exogenous carbohydrate oxidation during metabolically-matched steady-state exercise during energy balance and deficit.
80 minutes

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Time to exhaustion
Time Frame: 20 minutes
Determine the effects of consuming glucose compared to glucose plus fructose on time to exhaustion (min) during a graded exercise performance test during energy balance and deficit.
20 minutes

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
United States Army Research Institute of Environmental Medicine

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
February 1, 2024

Primary Completion (Estimated)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
December 1, 2024

Study Completion (Estimated)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
December 1, 2024

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
April 26, 2024

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
April 26, 2024

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
May 1, 2024

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
May 1, 2024

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
April 26, 2024

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
April 1, 2024

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • 23-15H

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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