Metabolic Adaptations to Weight Loss With and Without Exercise

Purpose

Study Purpose: The combination of caloric restriction and exercise is the most common first-line treatment for obesity-related disorders, yet we know very little about how these two very different treatments work together. A deeper understanding about mechanisms underlying the health benefits of adding exercise to a weight loss program will not only aid efforts to optimize more effective lifestyle interventions, but it can also uncover novel targets for the treatment/prevention of obesity-related diseases. Although a reduction in body fat is the fundamental adaptation to weight loss, we know almost nothing about the effects that adding exercise has on structural and functional changes within fat tissue that may further enhance metabolic health. This is very important because many obesity-related metabolic health complications are tightly linked with abnormalities in abdominal fat tissue. We argue exercise-induced modifications in abdominal fat tissue will reveal persistent health benefits even if some weight is regained Study Summary: 10% Weight Loss Phase - Subject participation in the study will involve a series of metabolic tests before, at midpoint, and after undergoing a 10% weight loss program (with or without exercise training depending on group randomization). During this, subjects will be randomized into one of two different experimental groups: 1. Moderate Intensity Continuous Training (MICT) exercise group 2. No exercise (control) group Follow-up Phase: After completing the metabolic testing post-weight loss, all study-related diet and exercise supervision will end and subjects will be free to make their own choices regarding diet and exercise/physical activity behavior. Subjects will then be asked to complete follow-up testing at 2-, 4- and 6- months post-weight loss. Total involvement in the study for each subject will likely be about 10-13 months (4-7 months during weight loss phase, 6 months during follow-up phase).

Conditions

  • Obesity
  • Metabolic Disease
  • Metabolic Syndrome
  • Insulin Sensitivity
  • Insulin Resistance
  • Weight Loss

Eligibility

Eligible Ages
Between 18 Years and 40 Years
Eligible Sex
All
Accepts Healthy Volunteers
Yes

Inclusion Criteria

  • Age: 18-40 - Body Mass Index: 30-40 kg/m2 - Weight stable (±3kg for greater than or equal to about 2 months) - No regularly planned exercise/physical activity - Women must have regularly occurring menses and must be premenopausal

Exclusion Criteria

  • EKG abnormalities - Evidence/history of cardiovascular disease, diabetes or other metabolic disease - Medications known to affect lipid or glucose metabolism - Pregnant or lactating - Tobacco or e-cigarette use - Prior experience of hypersensitivity to insulin, human albumin, and potassium chloride injection. - Allergies/hypersensitivity to local anesthetics of the amide type (e.g., lidocaine) - History of hyperkalemia or potential for developing hyperkalemia (including but not limited to taking drugs that may induce hyperkalemia such as cardiac glycosides or potassium sparing diuretics) - Anti-coagulant medication (e.g., Coumadin, Rivaroxaban) and Lidocaine allergy/sensitivity are exclusion criteria for the biopsy procedure.

Study Design

Phase
N/A
Study Type
Interventional
Allocation
Randomized
Intervention Model
Parallel Assignment
Primary Purpose
Basic Science
Masking
None (Open Label)

Arm Groups

ArmDescriptionAssigned Intervention
Experimental
Moderate Intensity Continuous Training (MICT) exercise group
45 minutes of continuous steady-state exercise at 70% maximal heart rate throughout the 10% weight loss phase of the study
  • Behavioral: MICT Exercise
    Subjects randomized into this group will complete a moderate intensity continuous exercise 4 days/week.
Experimental
No exercise (Control)
to remain sedentary (no planned physical exercise) throughout the duration of the 10% weight loss phase of the study
  • Behavioral: No Exercise (Control)
    Subjects randomized into this group will remain sedentary throughout the duration of the study.

Recruiting Locations

University of Michigan
Ann Arbor, Michigan 48109
Contact:
Suzette Howton
7346479850
suzetter@med.umich.edu

More Details

NCT ID
NCT05806801
Status
Recruiting
Sponsor
University of Michigan

Study Contact

Suzette M Howton
734-647-9850
suzetter@med.umich.edu