Resistance Training vs. Interval Training for Muscle Endurance

(LLSIT Trial)

Overseen By Cameron J Mitchell, PhD

Age: 18 - 65

Sex: Any

Trial Phase: Academic

Sponsor: University of British Columbia

Must not be taking: Blood thinners, Metformin, Benzodiazepines

Disqualifiers: Diabetes, Cancer, Cardiovascular, others

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

Compensation: Varies

Number of Visits: 2

Duration: 12 weeks

20 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial explores how different types of exercise can improve muscle endurance, aiding in daily activities like climbing stairs or sports such as rock climbing. Researchers compare two exercise methods: lifting lighter weights more frequently (low load resistance training) and performing intense bursts of exercise with rest intervals (high-intensity interval training). The goal is to determine which method better enhances the muscles' ability to sustain activity without fatigue. The study seeks participants aged 19-30 who have not engaged in structured exercise regularly in the past year and can communicate in English. As an unphased study, it offers a unique opportunity to contribute to valuable research that could refine exercise recommendations for improved muscle endurance.

Will I have to stop taking my current medications?

If you are taking blood-thinning medication or drugs that affect muscle metabolism, like Metformin or Benzodiazepines, you cannot participate in the trial. The protocol does not specify about other medications, so it's best to discuss with the trial team.

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

A previous study showed that low load resistance training (LLRET) is safe and effective for improving muscle endurance. Research shows that resistance training is safe for both children and adults. It strengthens muscles and benefits heart health, even for those with heart conditions.

Studies have also shown that high-intensity interval training (HIIT) is safe and can improve fitness levels. HIIT boosts heart health and aids in weight management, enhancing both aerobic (using oxygen) and anaerobic (not using oxygen) performance.

Both training methods have a strong safety record across different age groups and fitness levels. Participants generally handle them well, with no major safety concerns reported. ^{1 2 3 4 5}

Why are researchers excited about this trial's treatments?

Researchers are excited about these exercise techniques for boosting muscle endurance because they offer unique approaches compared to standard training methods. Low Load Resistance Training (LLRET) is distinctive in that it uses light weights with high repetitions to muscle fatigue, which might make it accessible to those who can't handle heavy lifting. On the other hand, Sprint/High Intensity Interval Training (SIT/HIIT) focuses on short, intense bursts of activity followed by rest, providing a powerful workout that can potentially yield results in less time than traditional endurance exercises. Both methods aim to enhance muscle endurance through different mechanisms, offering innovative alternatives to typical endurance training.

What evidence suggests that this trial's treatments could be effective for improving muscle endurance?

This trial will compare Low Load Resistance Training (LLRET) with Sprint/High Intensity Interval Training (HIIT) for muscle endurance. Research has shown that LLRET effectively increases muscle endurance by lifting lighter weights more frequently, building endurance without emphasizing strength. Participants in this trial may be assigned to the LLRET arm.

For those in the Sprint/High Intensity Interval Training arm, evidence suggests that HIIT improves both muscle endurance and aerobic fitness. HIIT involves short bursts of intense exercise followed by rest, enhancing overall fitness, including endurance. Both LLRET and HIIT improve muscle endurance, but they achieve this in slightly different ways. ^{1 3 4 6 7}

Are You a Good Fit for This Trial?

This trial is for healthy, English-speaking adults aged 19-30 who haven't done structured exercise training in the past year. It's not for those with a BMI outside of 18-30, smokers, or people with uncontrolled health issues like heart disease or diabetes.

Inclusion Criteria

All 'No' answers on the CSEP Get Active questionnaire or doctors' approval to participate

Untrained participants: no structured resistance and/or endurance training over the past 12 months (i.e., >2 hours per week of structured/periodized training)

I am between 19 and 30 years old.

Exclusion Criteria

Current use of cigarettes or other nicotine devices

Any medical condition impacting the ability to participate in maximal exercise

I have diabetes.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants undergo either Low Load Resistance Training (LLRET) or Sprint/High Intensity Interval Training (SIT/HIIT) for 12 weeks

12 weeks

2-3 times per week

Follow-up

Participants are monitored for changes in muscle endurance, mitochondrial content, and other physiological adaptations

4 weeks

What Are the Treatments Tested in This Trial?

Interventions

• Low Load Resistance training
• Sprint/High Intensity Interval Training

Trial Overview The study compares two types of workouts to see which is better at improving muscle endurance: lifting lighter weights many times (LLRET) and high-intensity interval training (HIIT). Participants will be assigned to one workout type to measure changes in their muscles.

How Is the Trial Designed?

Group I: Sprint/High Intensity Interval Training Experimental Treatment 1 Intervention

SIT/HIIT- 12 weeks (2-3 times/week), mix of SIT and HIIT (8-15 sets/session). SIT -30 second Super Maximal "Wingate style intervals" performed on a Kicking ergometer (single leg) with 4 minutes rest provided between sets (number of interval ranges from 4-5), load determined from DEXA leg lean mass and will not be altered throughout training. HIIT - 1-minute Submaximal efforts (90% single leg kicking ergometer VO2Peak Wattage) performed on a kicking ergometer (single leg) with 1 minute rest provided between sets (number of interval ranges from 8-10), if all sets completed wattage will be increased by 5watts for the next training session.

Group II: Low Load Resistance Training Experimental Treatment 1 Intervention

LLRET - 12 weeks (2-3 times/week) 3 sets of Knee extension exercise (single leg) done at 30%1- RM. Performed to failure with 3 minutes of rest between sets, weight lifted will be adjusted throughout the study to keep repetitions completed in a 20-30 repetition range.

Who Is Running the Clinical Trial?

University of British Columbia

Lead Sponsor

Trials

1,506

Recruited

2,528,000+

Citations

1. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC5983157/

Adaptations to Endurance and Strength Training - PMC Over a 12-wk endurance-training program, muscle mass has been reported to increase by 7% to 11% (Konopka et al. 2010; Trappe et al. 2011; Harber et al. 2012).

2. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC7927075/

Loading Recommendations for Muscle Strength ... Specifically, the theory postulates that heavy load training optimizes increases maximal strength, moderate load training optimizes increases muscle hypertrophy ...

3. clinicaltrials.gov clinicaltrials.gov/study/NCT05945641

Effect of Low-load Resistance Training vs. High-intensity ... Low load resistance exercise training (LLRET) has been definitively shown to improve local muscle endurance via numerous investigations. Resistance exercise ...

4. physoc.onlinelibrary.wiley.com physoc.onlinelibrary.wiley.com/doi/10.1113/EP091310

Distinct adaptations of muscle endurance but not strength or ... Low-load resistance training with and without BFR improved muscle strength and thickness to a similar extent. However, the number of repetitions ...

5. sciencedirect.com sciencedirect.com/science/article/abs/pii/S016749432300033X

Effect of resistance training on local muscle endurance in ... Analyses showed that resistance training has a large positive effect on local muscle endurance, irrespective of volume or loading intensity.

6. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC3483033/

Resistance training among young athletes: safety, efficacy ... Current research indicates that resistance training can be a safe, effective and worthwhile activity for children and adolescents.

7. ahajournals.org ahajournals.org/doi/10.1161/CIR.0000000000001189

Resistance Exercise Training in Individuals With and ... Resistance training is a safe and effective approach for improving cardiovascular health in adults with and without cardiovascular disease.