Skip to main content
OpenTrials
Not Yet Recruiting

NCT Number: NCT07761923

Preserving Muscle Mass During Incretin-Induced Weight Loss

Treatment with appetite suppressant drugs, including incretin-based receptor agonists, generally leads to clinically meaningful weight loss and reduced cardiometabolic risk. However, weight loss may include not only loss of adipose tissue but also loss of skeletal muscle mass, which ultimately may impair physical function and metabolic health.

Resistance training is an effective strategy to maintain or increase skeletal muscle mass during weight loss, but its effects during treatment with appetite suppressant obesity medications have been studied insufficiently. This study will investigate whether unilateral resistance training during incretin-based receptor agonist treatment can preserve or improve skeletal muscle mass. Additionally, the study will determine whether preservation of muscle is accompanied by the preservation of muscle function and/or molecular adaptations in skeletal muscle, adipose tissue and blood.

Participants will be adults with obesity who are about to start treatment with an incretin-based receptor agonist as part of routine clinical care. During the 13-week intervention, participants will perform supervised unilateral resistance training two times per week, training one leg while the other leg serves as an internal control. Data and tissue collection will take place before treatment start and after 13 weeks. Assessments include whole-body magnetic resonance imaging, blood sampling, skeletal muscle and adipose tissue biopsies, physical function tests, questionnaires, and monitoring of physical activity.

Not Yet Recruiting

Trial opening soon.

Get Notified

Key information

Conditions

Obesity (BMI > 35) Body Weight Nutrition Disorders Nutritional and Metabolic Diseases Obesity Overnutrition Overweight Pathological Conditions, Signs and Symptoms Signs and Symptoms

Age range

18 year–64 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Who can participate

Healthy volunteers accepted: No

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

Inclusion criteria

  • Adults aged 18-64 years with obesity.
  • Planned initiation of incretin-based obesity pharmacotherapy as part of routine clinical care.
  • Able to participate in supervised unilateral resistance training.
  • Able to complete physical function tests.
  • Able to attend study visits at the study center.
  • Able to provide written informed consent in the Swedish language.

Exclusion criteria

  • Contraindication to magnetic resonance imaging.
  • Medical condition preventing resistance training or physical function testing.
  • Medical condition preventing skeletal muscle or adipose tissue biopsy.
  • Inability to understand study information in Swedish or provide informed consent.

Treatment and study plan

Unilateral Resistance Training

Behavioral

Supervised resistance training of one leg, two sessions per week for 13 weeks, during incretin-based receptor agonist treatment. The trained leg will be randomly assigned, and the contralateral leg will serve as an internal within-participant control.

Primary outcomes

  1. Change in Anterior Thigh Skeletal Muscle Volume

    Time frame: From baseline to 13 weeks

    Change in skeletal muscle volume (L) of the anterior thigh muscles, measured by magnetic resonance imaging from baseline to 13 weeks. The primary comparison will be the difference in change from baseline to 13 weeks between the trained leg and the untrained contralateral leg.

Secondary outcomes

  1. Change in knee extension strength

    Time frame: From baseline to 13 weeks

    Change in lower-limb muscle strength measured using isokinetic (Nm) and isometric (Nm) knee extension tests.

  2. Change in muscle fatigue tolerance

    Time frame: From baseline to 13 weeks

    Change in peak torque (Nm) during repeated maximal concentric isokinetic contractions at 180°/s, assessed over 30 repetitions. Initial peak torque will be defined as the highest peak torque recorded during the first three repetitions, and final peak torque will be defined as the mean peak torque recorded during the last five repetitions. The decline in torque-generating capacity will be calculated as the absolute and relative decrease from initial to final peak torque.

  3. Change in whole-body skeletal muscle mass

    Time frame: From baseline to 13 weeks

    Change in whole-body skeletal muscle volume (L) measured by magnetic resonance imaging.

  4. Change in total body fat volume

    Time frame: From baseline to 13 weeks

    Change in total body fat volume (L) measured by magnetic resonance imaging.

  5. Change in liver fat fraction

    Time frame: From baseline to 13 weeks

    Change in liver fat fraction (%) measured by magnetic resonance imaging.

  6. Change in abdominal subcutaneous adipose tissue volume

    Time frame: From baseline to 13 weeks

    Change in abdominal subcutaneous adipose tissue volume (L), measured by magnetic resonace imaging.

  7. Change in visceral adipose tissue volume

    Time frame: From baseline to 13 weeks

    Change in visceral adipose tissue volume (L) measured by magnetic resonance imaging.

  8. Change in skeletal muscle fat fraction

    Time frame: From baseline to 13 weeks

    Change in anterior thigh muscle fat fraction (%), measured by magnetic resonance imaging.

Other outcomes

  1. Change in body mass

    Time frame: From baseline to 13 weeks

    Change in body mass during the intervention (kg).

  2. Change in blood pressure

    Time frame: From baseline to 13 weeks

    Change in resting systolic and diastolic blood pressure (mmHg).

  3. Change in skeletal muscle molecular profile

    Time frame: From baseline to 13 weeks

    Changes in molecular markers in skeletal muscle, including global (transcriptomics, proteomics, phosphoproteomics and metabolomics) and targeted gene expression, protein abundance, and specific molecular pathways.

  4. Change in adipose tissue molecular profile

    Time frame: From baseline to 13 weeks

    Changes in molecular markers in subcutaneous adipose tissue, including gene expression (transcriptomics), proteins (proteomics, phosphoproteomics & metabolomics), inflammatory markers, and specific molecular pathways.

  5. Change in health-related quality of life (RAND-36)

    Time frame: From baseline to 13 weeks

    Change in health-related quality of life using RAND-36. Each dimension results in a score from 0 to 100 (higher = better score).

  6. Change in health-related quality of life (EQ-5D-5L)

    Time frame: From baseline to 13 weeks

    Change in health-related quality of life using EQ-5D-5L. Each dimension results in a score from 1 (no problems) to 5 (extreme problems). The EQ visual analogue scale is rated from 0 (worst health you can imagine) to 100 (best health you can imagine)

  7. Change in cardiometabolic blood markers

    Time frame: From baseline to 13 weeks

    Change in blood markers including clinically relevant metabolic, inflammatory, endocrine and cardiovascular biomarkers.

  8. Change in energy intake and nutrient composition

    Time frame: From baseline to 13 weeks

    Change in self-reported energy intake (kcal), macronutrient intake, and micronutrient intake, measured by a food frequency questionnaire from baseline to 13 weeks.

  9. Change in physical activity

    Time frame: From baseline to 13 weeks

    Change in self-reported daily physical activity (minutes per week).

  10. Change in mitochondrial content

    Time frame: From baseline to 13 weeks

    Change in tissue (skeletal muscle and adipose tissue) mitochondrial content measured by citrate synthase activity (nmol/min/mg protein).

  11. Change in mitochondrial respiratory capacity

    Time frame: From baseline to 13 weeks

    Change in tissue (skeletal muscle and adipose tissue) mitochondrial respiratory capacity.

  12. Change in fat cell metabolism

    Time frame: From baseline to 13 weeks

    Change in fat cell lipolysis from adipose tissue biopsies.

  13. Change in immune cell populations

    Time frame: From baseline to 13 weeks

    Change in circulating immune cell populations.

  14. Change in sedentary time

    Time frame: From baseline to 13 weeks.

    Change in self-reported daily physical inactivity, measured as hours per day.

Study contacts

Contact information is provided by the study sponsor or research team.

Eric B Emanuelsson, PhD

CONTACT

[email protected]

+46730266626

Sponsors and collaborators

Lead sponsor

Karolinska Institutet

Other

Collaborators

  • Region Stockholm

Registry information

Official study title

Resistance Exercise Training to Preserve Muscle Mass and Physical Function During Incretin-Based Weight Loss

Acronym: INCRETraIN

Important dates

Study start
2026
Primary completion
2028
Study completion
2029
First posted
Aug 12, 2026
Registry last updated
Aug 12, 2026

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.

Related clinical trials

Published trials that share one or more normalized conditions with this study.