HIIT vs MICT Exercise for Sedentary Lifestyle

Overseen By Aubrey Roberts, MS

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: Stanford University

Must not be taking: Anticoagulants, Beta blockers, Antipsychotics, others

Disqualifiers: Diabetes, Hypertension, Cancer, 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: Unknown

Duration: 12 weeks

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial aims to explore how two types of exercise—high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT)—affect health in people with a sedentary lifestyle. Over 12 weeks, researchers will examine changes in fitness, muscle strength, and body composition. The trial suits individuals who have been mostly inactive for the past year, engaging in less than an hour of structured exercise per week. As an unphased trial, this study offers a unique opportunity to improve health and fitness through structured exercise.

Do I need to stop taking my current medications to join the trial?

Yes, you may need to stop taking certain medications to join the trial. The study excludes participants who have used any new drug or changed the dose of any drug in the last 3 months, and those taking specific medications like anticoagulants, beta blockers, and others listed in the exclusion criteria.

What prior data suggests that these exercise interventions are safe for sedentary individuals?

Research has shown that both high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) are generally safe for most people. Studies indicate that HIIT can improve fitness and reduce body fat, though there is a small risk of nonfatal heart-related incidents. For example, one study found 2 nonfatal heart attacks for every 46,364 hours of high-intensity exercise, indicating these events are rare. About 23% of people stop doing HIIT, but serious problems are uncommon.

MICT is also well-tolerated and known to improve heart health. Most research suggests it benefits both the heart and brain. Both types of exercise can help reduce sitting time and improve overall health when done with proper screening and guidance.

In summary, both HIIT and MICT are considered safe with the right precautions, especially when participants undergo screening to ensure they are healthy enough for exercise. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about this trial because it compares two distinct exercise methods, HIIT (High-Intensity Interval Training) and MICT (Moderate-Intensity Continuous Training), to see which is more effective for people with a sedentary lifestyle. Unlike traditional recommendations that often suggest moderate exercise like brisk walking or cycling, HIIT involves short bursts of intense activity followed by rest, which might offer a more efficient way to improve fitness in less time. MICT, on the other hand, maintains a steady, moderate pace and is already a well-known approach to enhancing cardiovascular health. The trial aims to uncover which exercise method could be more beneficial in improving health outcomes for inactive individuals, potentially reshaping exercise guidelines for sedentary lifestyles.

What evidence suggests that this trial's exercise interventions could be effective for improving health outcomes in sedentary individuals?

This trial will compare high-intensity interval training (HIIT) with moderate-intensity continuous training (MICT) for sedentary individuals. Research has shown that HIIT, which participants in this trial may receive, effectively improves exercise ability and heart and lung health. Studies suggest that HIIT can significantly reduce body fat, body mass index (BMI), and waist-to-hip ratio while increasing aerobic fitness and muscle strength. Meanwhile, MICT, another treatment option in this trial, also benefits heart health in inactive adults, but HIIT often proves more effective for certain fitness improvements. Both HIIT and MICT can enhance overall health, but HIIT might offer more noticeable results in a shorter time. These findings strongly support that exercise, whether HIIT or MICT, can greatly improve fitness and health in people with inactive lifestyles. ^{1 4 6 7 8}

Are You a Good Fit for This Trial?

This trial is for healthy adults over 18 who have been mostly inactive in the past year, with a BMI between >18 and <40. Participants should not be pregnant or planning pregnancy soon, nor have conditions like diabetes, abnormal bleeding, thyroid disease, severe heart issues, high blood pressure, extreme cholesterol levels, recent cancer treatment (except skin cancer), chronic infections or kidney problems. They shouldn't use certain medications or consume excessive alcohol/tobacco.

Inclusion Criteria

Body mass index (BMI) > 18 to < 40 kg/m2

Sedentary in the past year, defined as regular (structured) endurance exercise or resistance training, no more than 1 hour per week

Not be pregnant or lactating in the last 12 months, or planning to become pregnant for the next 4 months

Exclusion Criteria

Alcohol consumption

I have diabetes.

Abnormal blood lipid profile

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants undergo either high-intensity interval training (HIIT) or moderate-intensity continuous training (MICT) for 12 weeks

12 weeks

Follow-up

Participants are monitored for changes in health parameters such as multiomics profile, cardiorespiratory fitness, muscle strength, and body composition

4 weeks

What Are the Treatments Tested in This Trial?

Interventions

• Exercise intervention

Trial Overview

The study aims to compare two exercise programs: High-Intensity Interval Training (HIIT) and Moderate-Intensity Continuous Training (MICT). Over 12 weeks, participants will follow one of these routines to see which has a better effect on health outcomes such as fitness level changes, muscle strength improvements and body composition adjustments.

How Is the Trial Designed?

Group I: MICT group Experimental Treatment 1 Intervention

Participants randomized in this group will be assigned to 12 weeks of moderate-intensity continuous training.

Group II: HIIT group Experimental Treatment 1 Intervention

Participants randomized in this group will be assigned to 12 weeks high intensity interval training.

Group III: Control group Active Control 1 Intervention

Who Is Running the Clinical Trial?

Stanford University

Lead Sponsor

Trials

2,527

Recruited

17,430,000+

Published Research Related to This Trial

A 13-week study involving 54 physically inactive adults showed that a personalized exercise program combining moderate-intensity continuous training (MICT) and high-intensity interval training (HIIT) significantly improved cardiovascular fitness (VO2max) and metabolic health (MetS z-score) compared to a standardized MICT program and a control group.

All participants in the personalized MICT + HIIT group experienced positive changes in their fitness and metabolic health, indicating that tailored exercise prescriptions can lead to more effective and consistent health benefits than standard approaches.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Personalized Moderate-Intensity Exercise Training Combined with High-Intensity Interval Training Enhances Training Responsiveness. Byrd, BR., Keith, J., Keeling, SM., et al.[2020]

In a preliminary study involving overweight and obese adults, both high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) significantly reduced the amount of time participants spent being sedentary during the exercise intervention.

This suggests that engaging in either HIIT or MICT can effectively replace sedentary activities with more active behaviors, promoting overall health benefits.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The influence of high-intensity interval training and moderate-intensity continuous training on sedentary time in overweight and obese adults. Nugent, SF., Jung, ME., Bourne, JE., et al.[2022]

High-intensity interval training (HIIT) can lead to equal or greater improvements in aerobic capacity compared to traditional moderate-intensity continuous training (MICT), while also positively affecting body composition, glucose metabolism, blood pressure, and quality of life.

HIIT offers a significant time advantage, allowing individuals to achieve the same energy expenditure in a shorter duration, making it a practical option for both healthy adults and those with cardiovascular diseases.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Salutary effects of high-intensity interval training in persons with elevated cardiovascular risk. Fleg, JL.[2018]

A 16-week study involving 24 inactive elderly women demonstrated that high-intensity interval training (HIIT) significantly improved fasting plasma glucose levels and cardiorespiratory fitness compared to moderate-intensity continuous training (MICT).

Both HIIT and MICT led to reductions in body fat and waist circumference, but HIIT showed greater improvements in lipid profiles and functional abilities, indicating it is a more effective exercise option for enhancing physical health in elderly women.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

High-Intensity Interval Training Versus Moderate-Intensity Continuous Training for Improving Physical Health in Elderly Women. Rohmansyah, NA., Ka Praja, R., Phanpheng, Y., et al.[2023]

High-intensity interval training (HIIT) was found to be feasible and safe for older hospitalized patients, with an 88% completion rate among those who participated in at least one session, indicating good adherence to the program.

While HIIT showed a lower overall completion rate (44%) compared to moderate-intensity continuous training (MICT) (77%), both training methods did not result in significant differences in muscle strength, gait speed, or exercise capacity, suggesting that both can be effective rehabilitation options.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Feasibility and safety of high-intensity interval training for the rehabilitation of geriatric inpatients (HIITERGY) a pilot randomized study. Pires Peixoto, R., Trombert, V., Poncet, A., et al.[2020]

A 12-week study involving 46 sedentary obese individuals showed that high-intensity intermittent training (HIIT), moderate-intensity continuous training (MICT), and a shorter HIIT (1/2HIIT) all led to significant reductions in body weight, waist and hip circumference, and fat mass, while increasing fat-free mass and cardiovascular fitness, with no significant differences between the training methods.

Despite improvements in body composition and fitness, there were no significant changes in resting metabolism rate, nonexercise physical activity levels, or insulin response, suggesting that all three training protocols are equally effective for metabolic and cardiovascular benefits in this population.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

High-Intensity Interval Training and Isocaloric Moderate-Intensity Continuous Training Result in Similar Improvements in Body Composition and Fitness in Obese Individuals. Martins, C., Kazakova, I., Ludviksen, M., et al.[2018]

This study will evaluate the effects of high-intensity interval training (HIIT), moderate-intensity continuous training (MICT), and guideline-based physical activity on cardiovascular health, cognitive function, and motor function in 330 elderly sedentary patients with type 2 diabetes over 12 weeks.

The primary outcomes will focus on changes in glycosylated hemoglobin (HbA1c) and brain-derived neurotrophic factor (BDNF), with the hypothesis that both HIIT and MICT will improve health markers more effectively than the guideline-based program.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effects of high-intensity interval training, moderate-intensity continuous training, and guideline-based physical activity on cardiovascular metabolic markers, cognitive and motor function in elderly sedentary patients with type 2 diabetes (HIIT-DM): a protocol for a randomized controlled trial. Yu, P., Zhu, Z., He, J., et al.[2023]

In a study of 21 patients with myocardial infarction, both home-based high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) improved functional capacity and health outcomes over 12 weeks.

HIIT was found to be more effective than MICT in enhancing pulmonary function and lower extremity muscle strength, indicating that HIIT may offer additional benefits for patients recovering from a heart attack.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effect of home-based high-intensity interval training versus moderate-intensity continuous training in patients with myocardial infarction: a randomized controlled trial. Yakut, H., Dursun, H., Felekoğlu, E., et al.[2022]

This study will evaluate the effectiveness of high-intensity interval training (HIIT) compared to moderate-intensity continuous training (MICT) in improving aerobic capacity in dogs, involving 30 dogs over a 12-week training period.

The research aims to measure various physiological parameters, including maximal speed and lactate threshold, to determine if HIIT provides superior benefits in enhancing physical performance in dogs compared to MICT.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Efficacy of high-intensity interval training compared with moderate-intensity continuous training on maximal aerobic potency in dogs: Trial protocol for a randomised controlled clinical study. Orozco, SC., Arias, MP., Carvajal, PA., et al.[2023]

A study involving 11 manual wheelchair users found that both high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) were feasible and safe for home-based exercise, with no severe adverse events reported.

While neither training program significantly improved cardiorespiratory fitness or upper limb strength, participants in both groups reported moderate to significant subjective improvements, indicating potential benefits of these training methods.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Feasibility, Safety, and Preliminary Effectiveness of a Home-Based Self-Managed High-Intensity Interval Training Program Offered to Long-Term Manual Wheelchair Users. Gauthier, C., Brosseau, R., Hicks, AL., et al.[2022]

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