Exercise for Weight Loss

(WAX Trial)

Recruiting at 1 trial location

Overseen By Jeff F Horowitz, PhD

Age: 18 - 65

Sex: Any

Trial Phase: Academic

Sponsor: University of Michigan

Must not be taking: Lipid/glucose metabolism drugs

Disqualifiers: Cardiovascular disease, Diabetes, Tobacco, others

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

Compensation: Varies

Number of Visits: 3

68 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial aims to understand how adding exercise to a weight loss program affects fat tissue and overall metabolic health in people with obesity. Researchers seek to determine if exercise can provide lasting health benefits, particularly in reducing complications related to belly fat. Participants will be randomly assigned to either a moderate exercise group (Moderate Intensity Continuous Training, or MICT Exercise) or a no-exercise group (Control) during a 10% weight loss phase. Ideal candidates are those aged 18-40 with a Body Mass Index (BMI) of 30-40, who have stable weight and do not regularly exercise. As an unphased trial, this study offers participants the chance to contribute to innovative research that could enhance weight loss strategies and improve health outcomes.

Will I have to stop taking my current medications?

The trial does not specify if you need to stop taking your current medications, but you cannot participate if you are on medications that affect lipid or glucose metabolism, or if you take anti-coagulant medications.

What prior data suggests that this exercise program is safe for weight loss?

Studies have shown that moderate-intensity continuous training, the exercise used in this trial, is generally safe and well-tolerated by participants. Research indicates that this aerobic exercise can significantly reduce waist size and body fat, both positive indicators of improved health.

Some individuals might experience mild discomfort or soreness after exercising, but serious issues are rare. Notably, this type of exercise is commonly recommended for health improvement, suggesting its safety for most people.

In summary, moderate-intensity exercise is widely considered safe for most individuals, with benefits often outweighing the risks. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about the trial exploring Moderate Intensity Continuous Training (MICT) for weight loss because it emphasizes sustained, steady exercise, unlike the usual stop-and-go methods like high-intensity interval training (HIIT). MICT involves 45 minutes of continuous exercise at 70% of a person's maximal heart rate, potentially offering a more manageable and less strenuous alternative for individuals looking to lose weight. This approach could provide a new pathway for effective weight management without the need for intense or sporadic workouts.

What evidence suggests that adding exercise to a weight loss program is effective for improving metabolic health?

This trial will compare the effects of Moderate Intensity Continuous Training (MICT) with a control group receiving no exercise intervention. Studies have shown that MICT can lead to significant weight loss and improvements in metabolic health. Research indicates that performing aerobic exercise, such as MICT, for at least 150 minutes a week can help reduce waist size and body fat. This type of exercise also enhances the body's ability to burn fat and improves sugar processing. Despite its moderate intensity, these health benefits remain consistent. Thus, MICT not only aids in weight loss but also supports better overall health, particularly in managing fats and sugars in the body. ^{1 2 3 6 7}

Who Is on the Research Team?

Jeffrey Horowitz, PhD

Principal Investigator

University of Michigan

Are You a Good Fit for This Trial?

This trial is for premenopausal women aged 18-40 with a BMI of 30-40, who have stable weight and don't regularly exercise. It's not for those pregnant, lactating, with heart disease or metabolic diseases like diabetes, on certain medications affecting metabolism, using tobacco products, or with allergies to specific drugs.

Inclusion Criteria

Your body mass index (BMI) is between 30 and 40.

You do not regularly engage in exercise or physical activity.

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

Exclusion Criteria

You use tobacco or e-cigarettes.

You have had a bad reaction to insulin, human albumin, or potassium chloride injections before.

I have a history of heart disease, diabetes, or another metabolic condition.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

10% Weight Loss

Participants undergo a 10% weight loss program with or without exercise training, depending on group randomization. Metabolic tests are conducted before, at midpoint, and after the weight loss program.

4-7 months

Multiple visits for metabolic testing

Follow-up

Participants are monitored for safety and effectiveness after treatment. Follow-up testing is conducted at 2-, 4-, and 6-months post-weight loss.

6 months

3 visits (in-person) at 2-, 4-, and 6-months

What Are the Treatments Tested in This Trial?

Interventions

• MICT Exercise
• No Exercise (Control)

Trial Overview The study tests how adding moderate intensity continuous training (MICT) exercise affects fat tissue and metabolic health during a weight loss program compared to no exercise. Participants will undergo metabolic testing before, during and after achieving a 10% weight loss.

How Is the Trial Designed?

Group I: No exercise (Control) Experimental Treatment 1 Intervention

to remain sedentary (no planned physical exercise) throughout the duration of the 10% weight loss phase of the study

Group II: Moderate Intensity Continuous Training (MICT) exercise group Experimental Treatment 1 Intervention

45 minutes of continuous steady-state exercise at 70% maximal heart rate throughout the 10% weight loss phase of the study

Who Is Running the Clinical Trial?

University of Michigan

Lead Sponsor

Trials

1,891

Recruited

6,458,000+

Published Research Related to This Trial

In a study of 163 overweight and obese adults participating in 8 months of exercise training, those who achieved at least a modest weight loss (≥3%) showed significantly greater improvements in insulin sensitivity compared to those who did not lose weight.

The combination of aerobic exercise and modest weight loss also led to better outcomes in triglycerides and other lipid risk factors, suggesting that clinicians should encourage exercise and weight loss for enhanced cardiovascular health.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effects of aerobic training with and without weight loss on insulin sensitivity and lipids. Swift, DL., Houmard, JA., Slentz, CA., et al.[2018]

High-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) both significantly reduced body fat and waist circumference in overweight and obese adults over an average of 10 weeks, with no significant differences in effectiveness between the two methods.

HIIT required about 40% less training time than MICT while achieving similar body composition improvements, making it a more time-efficient option for weight management programs.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The effects of high-intensity interval training vs. moderate-intensity continuous training on body composition in overweight and obese adults: a systematic review and meta-analysis. Wewege, M., van den Berg, R., Ward, RE., et al.[2022]

In a study of 159 obese adults over 12 weeks, both moderate-intensity continuous training (MICT) and moderate-intensity interval training (MIIT) significantly reduced cardiovascular disease risk factors, with improvements seen in most health metrics except for high-density lipoproteins.

The MIIT group achieved weight loss more quickly than the MICT group, suggesting that interval training may be a more efficient exercise strategy for obese individuals looking to improve their health.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Moderate-Intensity Continuous Training Versus Moderate-Intensity Interval Training: Effects on Cardiometabolic Factors in Spanish Obese Adults. Sánchez-Polo, A., De-Llano, E., Gómez-Conesa, A.[2023]

High-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) both significantly reduce cardiovascular disease risk factors, including weight, BMI, body fat percentage, and total cholesterol, while also improving VO2max in adults with overweight and obesity.

HIIT is particularly effective in enhancing cardiopulmonary fitness compared to MICT, especially when HIIT intervals are 2 minutes or longer, while requiring less overall training time per session.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effects of HIIT and MICT on cardiovascular risk factors in adults with overweight and/or obesity: A meta-analysis. Su, L., Fu, J., Sun, S., et al.[2020]

A 12-week study involving 44 obese adults found that high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) resulted in similar weight loss and improvements in cardiovascular risk factors, indicating both are effective for obesity treatment.

HIIT led to a significantly greater increase in cardiorespiratory fitness compared to MICT, while also requiring less time per session, making it a more time-efficient exercise option for obese individuals.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effectiveness of high-intensity interval training for weight loss in adults with obesity: a randomised controlled non-inferiority trial. D'Amuri, A., Sanz, JM., Capatti, E., et al.[2022]

In a study involving 27 overweight/obese postmenopausal women, both high-intensity interval training (HIIT) and HIIT combined with resistance training (RT) were more effective than moderate-intensity continuous training (MICT) in reducing abdominal and visceral fat mass over 12 weeks.

While all training programs led to overall fat mass reduction, only the HIIT + RT group significantly increased muscle mass, indicating that adding resistance training can enhance body composition changes without affecting fat oxidation rates during exercise.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Moderate-Intensity Continuous Training or High-Intensity Interval Training with or without Resistance Training for Altering Body Composition in Postmenopausal Women. Dupuit, M., Rance, M., Morel, C., et al.[2021]

A meta-analysis of 10 studies involving 521 participants showed that exercise significantly reduces epicardial adipose tissue (EAT), with a strong effect size (g = 0.82), indicating its efficacy in improving cardiovascular health in individuals with overweight or obesity.

Endurance training specifically was confirmed to be effective in reducing EAT, while the effects of resistance training and different intensities of exercise (like HIIT vs. moderate-intensity) require further investigation.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Physical exercise and epicardial adipose tissue: A systematic review and meta-analysis of randomized controlled trials. Saco-Ledo, G., Valenzuela, PL., Castillo-García, A., et al.[2021]

In a study of 51 male patients with type 2 diabetes, 10-20-30 training significantly reduced HbA1c levels by 0.5 percentage points, while moderate-intensity continuous training (MICT) showed no change, highlighting the superior efficacy of the 10-20-30 method.

Only the 10-20-30 training led to a decrease in visceral fat mass, while both training methods effectively reduced total fat mass and increased maximum oxygen uptake (V̇O2 max), all achieved in a shorter training duration.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Efficacy of 10-20-30 training versus moderate-intensity continuous training on HbA1c, body composition and maximum oxygen uptake in male patients with type 2 diabetes: A randomized controlled trial. Baasch-Skytte, T., Lemgart, CT., Oehlenschläger, MH., et al.[2022]

High-intensity interval training (HIIT) showed a moderate beneficial effect on insulin sensitivity in adults with overweight and obesity, while moderate-intensity continuous training (MICT) did not demonstrate significant differences in weight, BMI, waist circumference, or body fat mass compared to HIIT.

The systematic review included 30 clinical trials with intervention durations ranging from 4 to 16 weeks, indicating that while HIIT may improve insulin sensitivity, both training methods are similarly effective for other weight-related outcomes.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effect of high-intensity interval training compared to moderate-intensity continuous training on body composition and insulin sensitivity in overweight and obese adults: A systematic review and meta-analysis. Sanca-Valeriano, S., Espinola-Sánchez, M., Caballero-Alvarado, J., et al.[2023]

Most randomized controlled trials (RCTs) show that exercise alone leads to only modest weight loss, and while combining exercise with dietary restriction can enhance weight loss, the energy deficit from exercise is often much smaller than that from diet alone.

High levels of exercise can lead to significant weight loss comparable to caloric restriction, but maintaining such exercise levels can be challenging for overweight or obese individuals, highlighting the importance of physical activity for long-term weight maintenance.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The role of physical activity in producing and maintaining weight loss. Catenacci, VA., Wyatt, HR.[2022]

In a study involving 13 overweight individuals, mixed-intensity interval endurance training (MI-ET) resulted in participants spending a greater percentage of their training time in a favorable heart rate zone compared to traditional continuous endurance training (ET) and circuit-interval resistance training (CRT).

Both MI-ET and CRT led to higher caloric expenditure per minute of exercise than ET, with CRT showing the highest overall caloric burn, but MI-ET provided significant benefits in terms of heart rate training zone engagement.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Examining matched acute physiological responses to various modes of exercise in individuals who are overweight. Clark, JE.[2016]

Interval training and moderate-intensity continuous training both effectively reduce body fat percentage, but interval training leads to significantly greater reductions in total absolute fat mass, with a 28.5% advantage over moderate-intensity training.

Subgroup analyses revealed that sprint interval training (SIT) is particularly effective for fat mass loss compared to moderate-intensity training, especially in supervised settings and among younger participants.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Is interval training the magic bullet for fat loss? A systematic review and meta-analysis comparing moderate-intensity continuous training with high-intensity interval training (HIIT). Viana, RB., Naves, JPA., Coswig, VS., et al.[2022]

In a 24-month study with 120 obese participants, those who started an exercise program immediately alongside behavioral modification (CWT1) lost the most weight (8.5 kg) and had the greatest reduction in waist circumference, highlighting the importance of early exercise in weight loss efforts.

Both exercise groups (CWT1 and CWT2) showed significant improvements in insulin levels compared to the control group, indicating that combining exercise with behavioral modification not only aids in weight loss but also enhances metabolic health.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effective Weight Loss and Maintenance by Intensive Start with Diet and Exercise. Kaikkonen, KM., Saltevo, SS., Korpelainen, JT., et al.[2019]

Citations

1. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC10048683/

Effect of High-Intensity Interval Training vs. Moderate ... Conclusions: The effect of HIIT on fat loss and CRF in the young and middle-aged is similar to or better than MICT, which might be influenced by age (18–45 ...

2. nature.com nature.com/articles/s41598-024-67331-z

Comparative effects of high-intensity interval training and ... The purpose of this study was to compare the effects of High-Intensity Interval Training (HIIT) and Moderate-Intensity Continuous Training (MICT) on weight, ...

3. sciencedirect.com sciencedirect.com/science/article/pii/S1728869X25000589

Compared to moderate-intensity continuous training, short- ... Overall, these results imply that exercise treatment, regardless of intensity, can improve fasting fat metabolism and glucose tolerance, consistent with ...

4. 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.

5. frontiersin.org frontiersin.org/journals/public-health/articles/10.3389/fpubh.2024.1487789/full

Effects of high intensity interval training and moderate ... The objective of this meta-analysis is to evaluate and compare the effectiveness of HIIT and MICT on enjoyment and affective responses in overweight or obese ...

6. sciencedirect.com sciencedirect.com/science/article/pii/S1728869X23000461

High-intensity interval training is not superior to continuous ... HIIT is not superior to CAT in reducing %BF or abdominal visceral fat in individuals characterized by excess weight.

7. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC8365736/

Effect of exercise training on weight loss, body composition ... No difference in weight, fat, and visceral loss was found between aerobic and high‐intensity interval training as long as energy expenditure was equal.