Muscle energy use and its link to metabolic inflexibility
Metabolic Inflexibility is Related to Elevated Muscle Anaerobic Glycolysis
This study will test whether overweight adults (BMI 25–30) with higher fasting lactate rely more on anaerobic muscle metabolism and are more prone to metabolic inflexibility compared with low‑lactate overweight and severely obese participants.
Quick facts
| Study type | Observational |
|---|---|
| Enrollment | 100 (estimated) |
| Ages | 18 Years to 50 Years |
| Sex | All |
| Sponsor | East Carolina University Academic / other |
| Locations | 1 site (Greenville, North Carolina) |
| Trial ID | NCT04320264 on ClinicalTrials.gov |
What this trial studies
Researchers will recruit adults aged 18–50 who are overweight (BMI 25–30) and measure fasting plasma lactate to identify the top and bottom quartiles. High‑ and low‑lactate overweight participants will undergo in vivo muscle lactate release measurements and respiratory exchange ratio (RER) testing to characterize whole‑body substrate use and metabolic flexibility. Severely obese subjects (BMI >40) will be included as a comparator group and studied before and after gastric bypass to observe whether surgical weight loss shifts muscle metabolism. The project aims to link reliance on anaerobic glycolysis in muscle to shifts from fat to carbohydrate oxidation and to test whether changing muscle substrate preference can normalize metabolic flexibility.
Who should consider this trial
Good fit: Ideal candidates are adults 18–50 who are overweight (BMI 25–30) able to attend metabolic testing and who fall into the top or bottom 25% of fasting lactate levels, with severely obese (BMI >40) patients enrolled as surgical comparators.
Not a fit: People with diabetes, heart disease, endocrine, hepatic, musculoskeletal or peripheral vascular disease, smokers, pregnant women, prisoners, mentally disabled individuals, or anyone taking medications that alter carbohydrate metabolism are excluded and unlikely to benefit from this protocol.
Why it matters
Potential benefit: If successful, the findings could enable a simple blood test (fasting lactate) to identify non‑obese people at higher risk of obesity and target them for early prevention.
How similar studies have performed: Preliminary data and prior work indicate bariatric surgery can normalize muscle lactate and that lactate relates to metabolism, but using fasting lactate screening to predict obesity risk in non‑obese people is a relatively novel and unproven approach.
Eligibility criteria
Show full inclusion / exclusion criteria
Inclusion Criteria: * 18-50 years old * BMI of 25 - 30 kg/m2 * BMI \> 40kg/m2 * Lactate levels in top and lower 25% Exclusion Criteria: * Pregnant women * Mentally disabled * Prisoners * Smokers * Subjects with heart disease * Type 1 and 2 diabetes * Endocrine disease * Hypertension * Musculoskeletal disease * Peripheral occlusion * Hepatic disease * Have had weight fluctuations exceeding + 3% in the previous 12 months * On medications which alter carbohydrate metabolism will not be studied
Where this trial is running
Greenville, North Carolina
- East Carolina University — Greenville, North Carolina, United States (Recruiting)
Study contacts
- Principal investigator: Joseph Houmard, PhD — East Carolina University
- Study coordinator: Terry Jones, PhD
- Email: joneste@ecu.edu
- Phone: 2527446249
How to participate
- Review the eligibility criteria above with your treating physician.
- Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
- Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.