The ISAR InflEx Trial (Inflammation and Exercise) (InflEx)

Impact of Different Exercise Intensities and Durations on Systemic Inflammation - The ISAR InflEx Trial (Inflammation and Exercise) -

A sedentary lifestyle and obesity are associated with chronic low-grade inflammation and an elevated risk of cardiovascular disease (CVD). This study aims to systematically characterize and compare the effects of three distinct exercise modalities - moderate-intensity, vigorous-intensity, and short-duration maximal exercise - each differing in duration and intensity, on systemic inflammation and immune function. The study investigates the potential of exercise as an effective anti-inflammatory intervention for the prevention of CVD.

Study Overview

• Status: Recruiting
• Conditions: Inflammation; Obesity (Disorder)
• Intervention / Treatment: Procedure: moderate-intensity exercise; Procedure: vigorous-intensity exercise; Procedure: short bouts of maximal exercise

Detailed Description

Adverse lifestyle behaviors, particularly sedentary habits, exacerbate inflammation and maladaptive immune responses, thereby promoting vascular inflammation and the development of atherosclerotic cardiovascular disease. Conversely, adopting healthier behaviors, including regular physical activity, may mitigate these effects, improve overall well-being, and prevent the progression from health to disease.

The ISAR InflEx trial aims to systematically evaluate the anti-inflammatory effects of physical exercise on systemic immunity. Healthy volunteers with a BMI of 25.0-30.0 kg/m² who lead a sedentary lifestyle and do not engage in any structured exercise will be enrolled in an exercise intervention.

The first group (n = 11 participants) will begin with a two-week period of moderate-intensity exercise, followed by a three-week break. This will be followed by two weeks of vigorous-intensity exercise, again followed by a three-week break, and finally two weeks of short bouts of maximal-intensity exercise.

The second and third groups (n = 11 each) will undergo the same procedure but in different sequences, starting with vigorous-intensity exercise and short bouts of maximal-intensity exercise, respectively. Blood samples will be collected before each exercise intervention, midway through the intervention, and after its completion to characterize and compare the systemic immune response. The primary outcome measure will be changes in blood leukocyte counts before and after each intervention. Participants will serve as their own controls, with pre-intervention measurements used as baseline values.

• Study Type: Interventional
• Enrollment (Estimated): 33
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Hendrik B Sager, MD; Phone Number: 00498912184025; Email: hendrik.sager@tum.de

Study Locations

• Germany
  • Bavaria
    • München, Bavaria, Germany, 80636
      • Recruiting
      • German Heart Centre
      • Contact: Hendrik B Sager, MD; Phone Number: 00498912184025; Email: hendrik.sager@tum.de

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• BMI 25.0 - 30.0 kg/m²
• age 18 - 45 years
• informed consent
• no regular physical activity (≤1x/week of structured exercise)
• willingness to strictly follow and adhere to the intervention protocol for the entire study

Exclusion Criteria:

• any acute or chronic illness
• pregnancy and breastfeeding
• active smoking
• Regular use of medication

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Sequential Assignment
• Masking: None (Open Label)

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: first arm; first moderate-intensity exercise, second vigorous-intensity exercise, third short bouts of maximal exercise	Procedure: moderate-intensity exercise; Guideline recommended 150 min/week of moderate-intensity aerobic physical exercise (40-50% VO2peak) on 5 days per week (30 min per session); Procedure: vigorous-intensity exercise; Guideline recommended 75 min/week of vigorous-intensity physical exercise (70-80% VO2peak) on 5 days per week (15 min per session); Procedure: short bouts of maximal exercise; Maximal vigorous-intensity physical exercise for 1 minute twice per day (>90% VO2peak) on 5 days per week (1 min per session, total of 2 min per day)
Experimental: second arm; first vigorous-intensity exercise, second short bouts of maximal exercise, third moderate-intensity exercise	Procedure: moderate-intensity exercise; Guideline recommended 150 min/week of moderate-intensity aerobic physical exercise (40-50% VO2peak) on 5 days per week (30 min per session); Procedure: vigorous-intensity exercise; Guideline recommended 75 min/week of vigorous-intensity physical exercise (70-80% VO2peak) on 5 days per week (15 min per session); Procedure: short bouts of maximal exercise; Maximal vigorous-intensity physical exercise for 1 minute twice per day (>90% VO2peak) on 5 days per week (1 min per session, total of 2 min per day)
Experimental: third arm; first short bouts of maximal exercise, second moderate-intensity exercise, third vigorous-intensity exercise	Procedure: moderate-intensity exercise; Guideline recommended 150 min/week of moderate-intensity aerobic physical exercise (40-50% VO2peak) on 5 days per week (30 min per session); Procedure: vigorous-intensity exercise; Guideline recommended 75 min/week of vigorous-intensity physical exercise (70-80% VO2peak) on 5 days per week (15 min per session); Procedure: short bouts of maximal exercise; Maximal vigorous-intensity physical exercise for 1 minute twice per day (>90% VO2peak) on 5 days per week (1 min per session, total of 2 min per day)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Changes in blood leukocyte levels pre- and post-intervention	From enrollment to the end of the last intervention at 15 weeks

Collaborators and Investigators

• Sponsor: Department of Cardiology German Heart Center Munich TUM University Hospital
• Collaborators: The German Heart Foundation; Klinikum rechts der Isar Technische Universität München

Study record dates

Study Major Dates

• Study Start (Actual): January 1, 2026
• Primary Completion (Estimated): June 1, 2027
• Study Completion (Estimated): June 1, 2027

Study Registration Dates

• First Submitted: April 15, 2026
• First Submitted That Met QC Criteria: April 15, 2026
• First Posted (Actual): April 22, 2026

Study Record Updates

• Last Update Posted (Actual): April 24, 2026
• Last Update Submitted That Met QC Criteria: April 21, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Keywords: physical activity; exercise; obesity; inflammation
• Additional Relevant MeSH Terms: Pathologic Processes; Nutrition Disorders; Overnutrition; Body Weight; Overweight; Pathological Conditions, Signs and Symptoms; Behavior; Nutritional and Metabolic Diseases; Signs and Symptoms; Obesity; Inflammation; Motor Activity
• Other Study ID Numbers: 2024-656-S-CB

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No