CompletedNot Applicable

Protective Effect of Exercise on Acute High-fat Overfeeding

United States50 participantsStarted 2025-02-10

Plain-language summary

Metabolic flexibility is the ability to switch rapidly from one substrate (i.e. fuel source) to another (e.g. fats to carbohydrates) in response to ingested foods. Worse metabolic flexibility is linked to worse metabolic outcomes, but exercise is thought to be protective against nutrient excess. We will conduct a standard oral glucose tolerance test (OGTT) to assess insulin resistance and metabolic flexibility. Participants will be randomized to a 24-hour hypercaloric, high-fat diet (HFD) with and without an exercise bout. During the hypercaloric HFD, participants will eat extra calories with more calories from fat than normal, which is expected to increase insulin resistance. After each arm of the high-fat diet, we will repeat the OGTT. During each OGTT, expired gases will be analyzed noninvasively to determine metablic flexibility. Insulin resistance will be determined with blood drawn during each OGTT. By comparing metabolic flexiblity and insulin resistance before and after the normal diet and after the high-fat diet intervention, a better understanding of how insulin resistance affects metabolism and how exercise can be protective will be developed.

Who can participate

Age range

20 Years – 40 Years

Sex

ALL

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AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.

Inclusion Criteria: * Males or females between the ages of 20 and 40 years * A body mass index (BMI) of 20.0 - 29.9 kg/m2. * Low risk for risk of injury or health complications as determined by physical activity readiness questionnaire (PARQ). Exclusion Criteria: * Are currently taking any antioxidant supplementation (daily multivitamin not included), prescribed non-steroidal anti-inflammatory drugs (NSAIDS), antibiotics, steroids, or probiotics. * Are currently taking any medications for management of cholesterol, diabetes, or body weight/obesity, or are undergoing hormone therapy. * Are unwilling or unable to comply with study procedures, at the discretion of the investigators. * Are unwilling to have biospecimens (blood and urine) collected and stored (only blood) for future research. * Pregnant women - A urine pregnancy test will be conducted prior to any testing procedures. * A history of disordered eating, including anorexia nervosa, bulimia nervosa, binge eating disorder, or avoidant restrictive food intake disorder or deemed high-risk for disordered eating via questionnaire. * A history of gastrointestinal diseases, such as galactosemia, gastroesophageal reflux disease (GERD), irritable bowel syndrome (IBS), Celiac disease, Crohn's disease, or lactose intolerance. * Individuals with known allergies to wheat or gluten, milk, soy, tree nuts (e.g., almonds, walnuts, pecans), or peanuts. * Deemed high risk for food insecurity via the Hunger Vital Sign screener. * Have …

Questions worth asking your doctor

Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.

1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?

Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.

Questions for the trial coordinator

The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.

1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?

A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.

What they're measuring

Insulin Sensitivity via Oral Glucose Insulin Sensitivity Index

Timeframe: Immediately following high fat diet intervention

Trial details

NCT IDNCT07633704

SponsorGeorge Washington University

Sponsor typeOTHER

Study typeINTERVENTIONAL

Primary completion2026-04-07

View on ClinicalTrials.gov More Insulin Sensitivity/Resistance trials