Physical Activity and Insulin Sensitivity Dynamics

NCT06776094 | Recruiting

• 1 other identifier: TEMPO
• Study Type: interventional
• Target: 8
• Locations: 1 country
• Sites: 1

Brief Summary

The study investigates the role of one single bout of exercise in mediating enhancement of muscle insulin sensitivity following a single bout of exercise. Furthermore, the study is aiming to elucidate the temporal development in insulin signaling, at the early timepoints of insulin stimulation that may be responsible for the enhanced muscle insulin sensitivity. This will be investigated in young healthy males subjected to a one-legged knee-extensor exercise followed by a hyperinsulinemic-euglycemic clamp, a setup known to enhance muscle insulin sensitivity.

Conditions

Insulin Sensitivity

Keywords

Exercise; Muscle insulin sensitivity; Muscle glucose uptake; GLUT4; Phosphoproteomics

Outcome Measures

Primary Outcomes (1)

• Insulin stimulated muscle glucose uptake

  Muscle glucose uptake during insulin stimulation in recovery from exercise (insulin sensitivity) will be determined based on Fick's principle. Thus, femoral arterio-venous difference (av difference) in blood glucose concentration will be multiplied by femoral arterial leg blood flow.

  Through study completion, approx. 1 year.

Secondary Outcomes (1)

• Posttranslational modification of proteins in muscle biopsies

  3 years

Other Outcomes (2)

• Imaging of transport protein

  1 year

• Maximum oxygen uptake

  Through study completion, approx. 1 year.

Study Arms (1)

Post-exercise insulin sensitivity

EXPERIMENTAL

Young healthy males will perform a single bout of knee-extensor exercise and insulin action is investigated 4 hours after cessation of exercise. Insulin action towards muscle glucose uptake will be investigated during a 120 min euglycemic hyperinsulinemic clamp.

Other: One-legged-knee extensor exercise; Procedure: Insulin infusion; Procedure: Muscle Biopsy Medication: Lidocaine; Other: Exercise

Interventions

One-legged-knee extensor exercise OTHER

1 hour of one-legged-knee-extensor exercise followed by 4 hours of rest

Post-exercise insulin sensitivity

Insulin infusion PROCEDURE

The hyperinsulinemic-euglycemic clamp is a well-established and recognized method for determining glucose uptake at a specific insulin infusion rate. It is a technique with which we have 25 years of uncomplicated experience. During the clamp, insulin (human recombinant insulin) is infused (1.42 mU/kg/min) into an arm vein (antecubital vein), while glucose (20% solution) is administered in an amount adjusted to maintain blood glucose (plasma glucose concentration) at basal levels. The amount of insulin administered raises the participant's plasma insulin concentration (blood concentration) to approximately 100 μU/mL, which is considered within the physiological range. Blood samples are collected and analyzed continuously for glucose content, allowing for the determination of glucose uptake at the whole-body level and across the legs. Later, these blood samples will also be analyzed for relevant metabolites and proteins, including insulin, to assess the metabolism of these substances.

Post-exercise insulin sensitivity

Muscle Biopsy Medication: Lidocaine PROCEDURE

During supine rest, the skin on the outer thigh, approximately 15 cm above the knee, is disinfected with chlorhexidine alcohol. Subsequently, 3-4 mL of local anesthetic (lidocaine 20 mg/mL) is administered into the skin, subcutaneous tissue, and the upper portion of the muscle using a very thin needle. A pinprick test is performed after a few minutes to ensure the anesthetic is effective. A small incision is then made in the skin and subcutaneous tissue to allow the biopsy needle to pass through to the muscle. Using the biopsy needle, a small sample of muscle tissue (approximately 150 mg) is collected. This may cause some discomfort but is very brief (\~1-2 seconds). The needle is removed, a sterile dressing is applied, and the participant can leave the facility after completing the study. The biopsy may result in mild muscle soreness for 2-3 days, similar to a minor muscle bruise. Regular physical activities can be resumed after the biopsy. However, it is advised to avoid swimming.

Post-exercise insulin sensitivity

Exercise OTHER

The participants' maximal oxygen uptake is determined through a test on a cycle ergometer before the start of the experiment. The test begins with a 20-minute warm-up at two different low workloads, after which the workload is gradually increased until the predetermined cadence can no longer be maintained, or the participant indicates exhaustion. During the test, the participant's exhaled air is collected. After completing the warm-up, it typically takes between 4 and 7 minutes to complete the test.

Post-exercise insulin sensitivity

Eligibility Criteria

• Age: 22 Years - 35 Years
• Sex: male
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Healthy individuals (no known diseases)
• No use of medication
• Non-smokers
• Male
• Aged 22-35 years
• Fitness level (VO2max, i.e., maximal oxygen uptake) between 30-50 mL O2/min/kg
• BMI between 28 and 35

You may not qualify if:

• Women
• Physical activity level (e.g., running, cycling, fitness, etc.) exceeding 6 hours per week
• Acute illness within 2 weeks prior to the study days
• Use of recreational drugs within 2 weeks prior to the study days

Sponsors & Collaborators

• University of Copenhagen: lead

Study Sites (1)

University of Copenhagen, August Krogh Section for Human and Molecular Physiology

Copenhagen, 2100, Denmark

RECRUITING

MeSH Terms

Conditions

Insulin Resistance; Motor Activity

Interventions

Insulin Infusion Systems; Exercise

Condition Hierarchy (Ancestors)

Hyperinsulinism; Glucose Metabolism Disorders; Metabolic Diseases; Nutritional and Metabolic Diseases; Behavior

Intervention Hierarchy (Ancestors)

Drug Delivery Systems; Drug Therapy; Therapeutics; Infusion Pumps; Equipment and Supplies; Artificial Organs; Surgical Equipment; Motor Activity; Movement; Musculoskeletal Physiological Phenomena; Musculoskeletal and Neural Physiological Phenomena

Study Officials

• Jørgen FP Wojtaszewski, Prodessor

  Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Denmark

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Jørgen FP Wojtaszewski, Professor

CONTACT

+4535321625; jw@nexs.ku.dk

Nicolai S Henriksen, MSc

CONTACT

+4560110222; nsh@nexs.ku.dk

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Professor

Study Record Dates

• First Submitted: January 9, 2025
• First Posted: January 15, 2025
• Study Start: May 5, 2025
• Primary Completion: August 26, 2025
• Study Completion (Estimated): January 1, 2027
• Last Updated: December 2, 2025

Record last verified: 2025-12

Data Sharing

• IPD Sharing: Will not share

Locations

DK (1)