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Completed

NCT Number: NCT03839641

Novel Approach to Assess Metabolic Flexibility in a Respiratory Chamber

The overarching aim of this study: To determine the effect of different meal compositions (high- vs. low-fat) on metabolic flexibility as it relates to meal-stimulated change in respiratory quotient (ΔRQ1) and sleep (ΔRQ2) metabolic flexibility, as well as the time course changes in respiratory quotient, RQ (i.e., peak RQ, time to peak RQ, nadir RQ, time to nadir, slope).

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Key information

Conditions

Diabetes Mellitus, Type 2 Diabetes Mellitus Endocrine System Diseases Glucose Metabolism Disorders Metabolic Diseases Nutritional and Metabolic Diseases

Age range

18 year–40 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Pennington Biomedical Research Center

Baton Rouge, Louisiana, 70808-4124, United States

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Eligibility criteria include:
  • Healthy male or female
  • Ages 18-40 y
  • BMI between 20 kg/m2 and 30 kg/m2 (±0.5 kg/m2 will be accepted)
  • Are willing to consume pre-prepared meals
  • Are willing to maintain current physical activity, sleep schedule, and dietary habits during the study.
  • Medically cleared for participation in the study by Medical Investigator

Exclusion criteria

  • Participants are ineligible to participate (or will be excluded from participating in this study) if they meet any of the following criteria:
  • Unstable weight in the last 3 months [gain or loss >7 lb (or 3.2 kg)]
  • Currently working shift work
  • Smoking or use of tobacco products within the last 3 months
  • Amenorrhea (or absence of regular monthly cycles)
  • History of clinically diagnosed diabetes or a fasting blood glucose >126 mg/dL
  • Average screening blood pressure >140/90 mmHg
  • Previous bariatric surgery (or other surgeries) for obesity or weight loss
  • Use of medications affecting metabolism or sleep
  • History of neurological disease
  • History of cardiovascular disease (or other chronic diseases)
  • Pregnant, planning to become pregnant, or breastfeeding
  • Adherence to special restrained diets (e.g., low-carbohydrate, low-fat, or vegetarian/vegan diets) over the last 3 months.

Treatment and study plan

high fat meal

Other

60% fat meal

low fat meal

Other

20% fat meal

Primary outcomes

  1. Overnight Respiratory Exchange Ratio

    Time frame: 12 hours

    12-h mean of respiratory exchange ratio following each meal type.

    measurement interval = 12h following start of meal (7pm)

    The respiratory exchange ratio refers to the proportion of macronutrients being oxidized. A respiratory exchange ratio value of 1.0 indicates only carbohydrates are being oxidized, while a ratio value of 0.7 indicates only fats are being oxidized. Intermediate values, such as 0.85, indicates that both carbohydrate and fats are being oxidized.

Secondary outcomes

  1. Sleep Respiratory Exchange Ratio

    Time frame: 3 h

    mean of respiratory exchange ratio following each meal type during sleep period, 2am-5am., 2am-5am.

    measurement interval = 3h (2am-5am)

    The respiratory exchange ratio refers to the proportion of macronutrients being oxidized. A respiratory exchange ratio value of 1.0 indicates only carbohydrates are being oxidized, while a ratio value of 0.7 indicates only fats are being oxidized. Intermediate values, such as 0.85, indicates that both carbohydrate and fats are being oxidized.

  2. Peak Increase in Respiratory Exchange Ratio

    Time frame: 4 h

    mean of peak increase in respiratory exchange ratio (Peak values - baseline values) following each meal type

    Peak values were defined as the peak respiratory exchange ratio value measured during the post-meal period, 6pm-10pm.

    Baseline values were measured 1h prior to meal (5:00-5:45pm)

    measurement interval of peak values= 4h (6pm-10pm)

    A larger value in this measurement indicates that more carbohydrate than fats were being oxidized as fuel during the measurement period.

  3. Peak Decrease in Respiratory Exchange Ratio

    Time frame: 12 h

    mean of peak decrease in respiratory exchange ratio (baseline values -nadir values) following each meal type

    Peak values were defined as the peak respiratory exchange ratio value measured during the post-meal period, 6pm-10pm.

    Baseline values were measured 1h prior to meal (5:00-5:45pm)

    measurement interval of nadir values= 12h (6pm-6am)

    A larger value in this measurement indicates that more fats than carbohydrate were being oxidized as fuel during the measurement period.

  4. Time to Peak Respiratory Exchange Ratio

    Time frame: 12 h

    Average time from meal to peak respiratory exchange ratio value

    This measurement indicates how long on average it took form the onset of the meal, 6pm, for the participants to achieve their highest/peak respiratory exchange ratio value.

  5. Time to Nadir Respiratory Exchange Ratio

    Time frame: 12 h

    Average time from meal to nadir respiratory exchange ratio value

    This measurement indicates how long on average it took form the onset of the meal, 6pm, for the participants to achieve their lowest/nadir respiratory exchange ratio value.

  6. Slope of Respiratory Exchange Ratio

    Time frame: 12 h

    This value indicates the speed and magnitude of the participants change in respiratory exchange ratio between the peak and nadir values.

    A more negative value in this measurement indicates either a short time interval between the highest and lowest respiratory exchange ratio values measured and/or a large difference between the highest and lowest values of respiratory exchange ratio values measured.

Sponsors and collaborators

Lead sponsor

Pennington Biomedical Research Center

Other

Registry information

Acronym: METFLEX

Important dates

Study start
2019
Primary completion
2019
Study completion
2020
First posted
Feb 15, 2019
Registry last updated
Sep 17, 2021

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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