Exercise for Obesity

(CAT Trial)

Overseen By Suzette Howton

Age: 18 - 65

Sex: Any

Trial Phase: Academic

Sponsor: University of Michigan

Must not be taking: Lipid/glucose metabolism, Inflammation

Disqualifiers: Cardiovascular, Metabolic, Tobacco, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Approved in 1 Jurisdiction This treatment is already approved in other countries

Compensation: Varies

Number of Visits: 1

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial aims to understand how regular exercise affects the structure and function of belly fat. Researchers will compare fat samples from people who exercise regularly to those who do not. Participants will also undergo an Oral Glucose Tolerance Test to assess how their bodies handle sugar. This trial suits individuals aged 18 to 40 with a BMI between 23 and 35, who are generally healthy, have maintained stable weight, and do not smoke. As an unphased study, this trial allows participants to contribute to valuable research on exercise and health.

Will I have to stop taking my current medications?

If you are taking medications that affect lipid (fat) or glucose (sugar) metabolism, or inflammation, you may need to stop them to participate in this trial.

Is there any evidence suggesting that this trial's treatments are likely to be safe?

Research shows that exercise is generally safe for most people. Studies have found that regular physical activity can lower the risk of death by 20% to 30% compared to inactivity. This indicates that exercise is usually well-tolerated and provides health benefits.

For people with obesity, activities like running or swimming can help reduce body fat and improve overall health. One study found that exercising for at least 150 minutes a week significantly decreased waist size and body fat.

Overall, regular exercise is linked to positive health outcomes with minimal risk of negative effects. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Most treatments for obesity focus on diet, medication, or surgery. However, exercise is unique because it addresses obesity by enhancing the body's ability to manage glucose levels through physical activity. Researchers are excited about this approach because exercise can improve how quickly glucose is cleared from the blood, which is crucial for managing weight and preventing related conditions like diabetes. Unlike medication or invasive procedures, exercise is a natural and sustainable method that can offer additional health benefits, such as improved cardiovascular health and increased energy levels.

What evidence suggests that exercise is effective for obesity?

Studies have shown that regular exercise can help reduce obesity. Aerobic activities like brisk walking or cycling burn calories and lower body fat. Research suggests that engaging in at least 150 minutes of aerobic exercise each week can significantly reduce waist size and body fat. Lifting weights, or resistance training, also reduces body fat, especially when combined with a healthy diet. Interval training, which includes short bursts of intense activity, effectively addresses overweight and obesity. Overall, different types of exercise can manage weight and improve body shape.

Note: This trial includes an Oral Glucose Tolerance Test, which assesses glucose metabolism and is not a treatment for obesity. ^{1 3 4 6 7}

Who Is on the Research Team?

Jeffrey F Horowitz, PhD

Principal Investigator

University of Michigan

Are You a Good Fit for This Trial?

This trial is for adults aged 18-40 with a BMI of 23-35, who are not pregnant or lactating, and have stable weight. Participants should be free from cardiovascular/metabolic diseases, not use tobacco products or medications affecting metabolism.

Inclusion Criteria

Body Mass Index: 23-35 kg/m2

I am a woman who has regular periods and am not in menopause.

Exclusion Criteria

Tobacco or e-cigarette users

Weight instability ≥ ± 6 pounds in the last 6 months

Blood pressure > 140/90 mmHg

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Experimental Trial

Subjects will complete an Oral Glucose Tolerance Test in which glucose is given and blood samples are taken every 15 minutes over a 2 hour period

1 day

1 visit (in-person)

Follow-up

Participants are monitored for safety and effectiveness after treatment

4 weeks

What Are the Treatments Tested in This Trial?

Interventions

• Exercise
• Oral Glucose Tolerance Test

Trial Overview The study aims to compare abdominal fat tissue between regular exercisers and non-exercisers using an Oral Glucose Tolerance Test to understand differences in structure and function.

How Is the Trial Designed?

Group I: Oral Glucose Tolerance Test Experimental Treatment 1 Intervention

Subjects will complete an Oral Glucose Tolerance Test in which glucose is given and blood samples are taken every 15 minutes over a 2 hour period to determine how quickly the glucose is cleared from the blood.

Who Is Running the Clinical Trial?

University of Michigan

Lead Sponsor

Trials

1,891

Recruited

6,458,000+

Published Research Related to This Trial

Exercise has numerous benefits for individuals with obesity, including aiding in weight loss and improving cardiovascular health, but the direct impact on weight loss from exercise alone is modest, typically resulting in only a few kilograms of weight loss.

Physical activity is crucial for managing type 2 diabetes and preventing its complications, and a structured approach like the 5 A's strategy can help healthcare professionals effectively support patients in overcoming barriers to increasing their physical activity levels.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Physical activity in management of persons with obesity. Oppert, JM., Bellicha, A., Ciangura, C.[2021]

A structured, home-based exercise program significantly improved physical performance and quality of life in patients with obesity, as demonstrated by a cohort of 151 participants over a 3-month period.

After the program, participants showed notable enhancements in walking distance, speed, and VO2max, indicating that even simple exercise routines can have substantial health benefits for individuals with obesity.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Usefulness of an Easy, Structured, and Home-Based Exercise Program to Improve Physical Performance and Quality of Life in a Patient's Cohort with Obesity. López-López, CO., Montes Castillo, ML., Aguilar-Serralde, CA., et al.[2023]

A systematic review of 116 studies found that both aerobic and anaerobic training significantly improve body composition and physical fitness in individuals with obesity, with effect sizes ranging from trivial to very large.

Physical training not only reduces body weight and fat mass but also increases fat-free mass and VO2max, indicating enhanced cardiovascular fitness, suggesting that various intensities of exercise can be beneficial for weight loss and overall health.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effects of physical training on anthropometrics, physical and physiological capacities in individuals with obesity: A systematic review. Zouhal, H., Ben Abderrahman, A., Khodamoradi, A., et al.[2021]

A systematic review of 13 studies found that both aerobic and strength exercises are crucial for effectively treating individuals with morbid obesity, whether they are undergoing medical or surgical interventions.

It is essential to tailor the volume and intensity of exercise programs to ensure patient adherence, highlighting the need for individualized exercise plans for optimal results.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Physical exercise and morbid obesity: a systematic review. Fonseca-Junior, SJ., Sá, CG., Rodrigues, PA., et al.[2019]

Combining physical exercise with energy restriction diets leads to greater weight loss than exercise alone, making it the most effective strategy for significant weight loss.

Engaging in at least 150 minutes of moderate-intensity or 75 minutes of vigorous-intensity aerobic exercise weekly, along with resistance training, is recommended for weight loss and maintenance, which also helps improve obesity-related health issues like diabetes and cardiovascular disease.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Obesity and physical exercise. Celik, O., Yildiz, BO.[2021]

In a 12-week study involving 38 obese patients, those receiving weekly encouragement from personal trainers showed significant improvements in physical activity levels, pain reduction, and overall health status compared to a control group.

While there was no significant change in body weight, the structured physical activity program led to enhanced quality of life for the participants, highlighting the importance of behavioral changes in managing obesity.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

PHYSICAL ACTIVITY, QUALITY OF LIFE AND BODY IMAGE OF CANDIDATES TO BARIATRIC SURGERY. Barreto, BLM., Lima, JS., Albuquerque, DB., et al.[2019]

Regular exercise is crucial for managing obesity, contributing to weight loss, maintenance, and improved metabolic health, with endurance training being the most effective type of exercise.

Higher levels of physical activity are associated with better weight loss maintenance, although establishing a direct cause-and-effect relationship remains challenging.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Exercise in the management of obesity. Petridou, A., Siopi, A., Mougios, V.[2019]

Exercise can be beneficial for obese individuals, but many are unable to tolerate physical activity due to their weight, which limits their ability to gain fitness and improve body composition.

The most effective treatment for obesity combines dietary restriction and exercise, with a greater emphasis on diet for those with severe obesity and a focus on exercise for managing mild obesity or preventing weight gain.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effect of exercise on obesity. Garrow, JS.[2019]

Physical activity is crucial for treating obesity, as it not only helps reduce fat but also prevents the loss of muscle mass and improves cardiovascular health, making it more than just a weight loss tool.

Successful physical activity programs for obese individuals require careful consideration of the type, intensity, duration, and frequency of exercise, along with addressing real-life barriers such as time constraints and lack of support.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

[Physical activity in the treatment of obesity]. Svacinová, H., Matoulek, M.[2010]

This randomized controlled trial will assess the impact of exercise training combined with a very low energy diet (VLED) on body composition and health outcomes in 60 clinically severe obese women over 12 months.

The study aims to provide evidence on whether adding exercise to a VLED can lead to greater improvements in physical function, quality of life, and cardiometabolic risk factors compared to diet alone, addressing a gap in research for class II and III obesity.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The functional and clinical outcomes of exercise training following a very low energy diet for severely obese women: study protocol for a randomised controlled trial. Miller, CT., Fraser, SF., Selig, SE., et al.[2018]

Citations

1. ncbi.nlm.nih.gov ncbi.nlm.nih.gov/books/NBK539893/

Exercise and Fitness Effect on Obesity - StatPearls - NCBI - NIH Exercise, especially aerobic, increases energy expenditure, reducing fat tissue and obesity. 150-300 minutes of moderate activity weekly is ...

2. jamanetwork.com jamanetwork.com/journals/jamanetworkopen/fullarticle/2828487

Aerobic Exercise and Weight Loss in Adults: A Systematic ... Aerobic exercise at least 150 minutes per week was associated with clinically important reductions in waist circumference and measures of body fat.

3. nature.com nature.com/articles/s41598-025-11076-w

Effects of resistance training and aerobic ... This study investigated the effectiveness of a resistance and aerobic training model among 71 middle-aged participants aged 30–60 (mean age ...

4. ahajournals.org ahajournals.org/doi/10.1161/CIRCOUTCOMES.121.008243

Comparative Efficacy of 5 Exercise Types on ... Interval training, although intense, appears to be an effective and time-efficient exercise mode for individuals with overweight and obesity to ...

5. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC9285060/

Resistance training effectiveness on body composition and ... Interventions involving resistance training and caloric restriction were the most effective for reducing body fat percentage (ES = −3.8%, 95% CI: −4.7 to −2.9%, ...

6. who.int who.int/news-room/fact-sheets/detail/physical-activity

Physical activity People who are insufficiently active have a 20% to 30% increased risk of death compared to people who are sufficiently active. Regular physical ...

7. cdc.gov cdc.gov/pcd/issues/2024/23_0347.htm

Weight Loss in Short-Term Interventions for Physical ... Short-term multicomponent interventions involving physical activity and nutrition can achieve weight loss for adults with overweight or obesity.