Resistance Training for Muscle Growth

(SLML Trial)

Age: 18 - 65

Sex: Any

Trial Phase: Academic

Sponsor: University of British Columbia

Must not be taking: 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: 4

Duration: 10 weeks

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial explores whether applying peak force at different muscle lengths during resistance training enhances muscle growth and strength. Participants will test two workout types: one applying force when the muscle is more stretched (LONG resistance training) and the other when it's more contracted (SHORT resistance training). The study seeks young adults who have not engaged in regular resistance training in the past year. Participants will work out twice a week for 12 weeks, with strength and muscle size measured at the beginning and end. As an unphased study, this trial offers a unique opportunity to contribute to the scientific understanding of muscle growth and strength.

Will I have to stop taking my current medications?

The trial requires that you stop taking any drugs that alter skeletal muscle metabolism, such as Metformin or Benzodiazepines, and avoid Omega-3 supplements like fish oil for at least 6 weeks before participating.

What prior data suggests that this resistance training protocol is safe for young and healthy adults?

Research has shown that resistance training is generally safe and can increase muscle size and strength. Studies have found that regular resistance training leads to muscle growth and improved physical function. Those who engage in resistance training regularly tend to have more muscle mass and strength compared to non-exercisers.

Additionally, resistance training is safe for young people, including children and teenagers, when performed with proper techniques. Therefore, the training methods used in this trial (LONG and SHORT resistance training) are likely to be well-tolerated by participants.

Overall, resistance training is known for its safety and effectiveness in building muscle strength and size, making it a promising approach for achieving the goals of this study. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about the LONG and SHORT resistance training protocols because they offer a fresh approach to building muscle by tailoring exercise duration and intensity. Unlike traditional strength training methods that typically focus on uniform workout routines for all muscle groups, these protocols use a unique within-subject design to customize training based on individual muscle responses. This could potentially enhance muscle growth and strength more effectively by optimizing the workout for each limb. By comparing different timeframes and intensities, this trial aims to uncover the most efficient way to achieve muscle growth, possibly transforming how we approach resistance training.

What evidence suggests that this trial's resistance training protocols could be effective for muscle growth?

Research has shown that resistance exercises with more stretched muscles (LML-RT) might lead to bigger and stronger muscles compared to less stretched muscles (SML-RT). Studies have found that lifting heavy weights effectively increases muscle strength, with a 98.2% chance of better results. In this trial, participants will engage in both LONG and SHORT resistance training sessions. Using a full range of motion, similar to the LONG condition, can improve muscle size, strength, speed, and power. Both LONG and SHORT resistance training can enhance muscle strength and size, but the LONG condition is expected to yield better results. These findings suggest that applying maximum force when muscles are more stretched during training could be more effective for muscle growth and strength gains. ^{6 7 8 9 10}

Who Is on the Research Team?

Dr. Cameron Mitchell

Principal Investigator

University of British Columbia, School of Kinesiology

Are You a Good Fit for This Trial?

This trial is for young, healthy adults interested in muscle growth. Participants will engage in resistance training and undergo strength testing. They must be available to train twice a week for 12 weeks and visit the UBC MRI Research Facility at the beginning and end of the study.

Inclusion Criteria

Able to understand and communicate in English

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

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

Exclusion Criteria

BMI lower than 18 or greater than 30

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

Initial Testing

Participants undergo initial strength testing and MRI measurements

1 week

1 visit (in-person)

Treatment

Participants engage in resistance training under LONG and SHORT conditions

10 weeks

2 visits per week (in-person)

Final Testing

Participants undergo final strength testing and MRI measurements

1 week

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

• LONG and SHORT Resistance Training

Trial Overview The trial tests two resistance training conditions: LONG (peak force at long muscle length) and SHORT (peak force at short muscle length). It aims to determine which condition leads to greater muscle hypertrophy and strength gains using Prime Fitness machines set differently.

How Is the Trial Designed?

Group I: SHORT and LONG Training Protocol Experimental Treatment 4 Interventions

Using a within subject design, participants will have the arms and legs from both left and right side of the body (divided by sagittal plane) randomly assigned to either LONG or SHORT conditions. Participants will then engage in maximal strength testing on Prime Fitness machines (1RM) as well as isokinetic strength testing (Biodex) in weeks 1 and 12. Participants will engage in the LONG and SHORT training sessions for 10 weeks in duration from week 2 until week 11.

Who Is Running the Clinical Trial?

University of British Columbia

Lead Sponsor

Trials

1,506

Recruited

2,528,000+

Published Research Related to This Trial

Resistance exercise triggers a significant acute hormonal response, particularly in anabolic hormones like testosterone and growth hormone, which are crucial for muscle growth and remodeling, rather than relying solely on chronic hormonal changes.

High-volume, moderate to high-intensity resistance training with short rest intervals is most effective for maximizing acute hormonal elevations, which are essential for optimizing muscle adaptation and performance.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Hormonal responses and adaptations to resistance exercise and training. Kraemer, WJ., Ratamess, NA.[2022]

Resistance training significantly improves functional status, health, and quality of life in older adults by increasing muscle strength and mass, which are crucial for combating sarcopenia, a common age-related condition.

The review suggests that resistance training enhances muscle quality and power, promotes better body composition, and encourages physical activity, while cautioning that excessive aerobic training alongside resistance training may hinder strength gains if not managed properly.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effects of resistance training on older adults. Hunter, GR., McCarthy, JP., Bamman, MM.[2022]

Resistance training (RT) at a longer range of motion (LR) leads to significantly greater improvements in muscle strength and size compared to a shorter range of motion (SR), as shown in a study with 16 recreationally active participants over 8 weeks.

During a 4-week detraining period, the SR group experienced a faster decline in strength compared to the LR group, indicating that longer range training may provide more lasting benefits in muscle adaptations.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Impact of range of motion during ecologically valid resistance training protocols on muscle size, subcutaneous fat, and strength. McMahon, GE., Morse, CI., Burden, A., et al.[2022]

Resistance training (RT) significantly reduces all-cause mortality and the incidence of cardiovascular disease while improving physical functioning in adults, based on an analysis of 11 systematic reviews involving over 382,000 participants.

Although adverse events were not consistently reported, serious adverse events related to RT were uncommon, suggesting that the benefits of resistance training outweigh the potential harms.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Resistance training and health in adults: an overview of systematic reviews. El-Kotob, R., Ponzano, M., Chaput, JP., et al.[2021]

Resistance training (RT) is the only non-drug method proven to effectively counteract age-related declines in muscle mass, strength, and power, while also reducing risks of various health issues like cardiovascular disease and depression.

Minimal-dose RT strategies, which involve lower training volumes and can be performed with minimal equipment, are effective in improving strength and functional ability, making it easier for more people to participate and potentially enhancing overall health outcomes.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Minimal-Dose Resistance Training for Improving Muscle Mass, Strength, and Function: A Narrative Review of Current Evidence and Practical Considerations. Fyfe, JJ., Hamilton, DL., Daly, RM.[2022]

Ten weeks of resistance training can lead to significant health benefits, including an increase in lean muscle mass by 1.4 kg, a 7% boost in resting metabolic rate, and a reduction in fat weight by 1.8 kg.

Resistance training not only improves physical performance and cognitive abilities but also helps in managing type 2 diabetes and enhancing cardiovascular health by reducing visceral fat and improving cholesterol levels.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Resistance training is medicine: effects of strength training on health. Westcott, WL.[2022]

Citations

1. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC8126497/

Resistance Training Load Effects on Muscle Hypertrophy ... The results of the consistency models indicate that high-load resistance training has a probability of 98.2% to induce greater effects on muscle strength, also ...

2. sciencedirect.com sciencedirect.com/science/article/pii/S2666337625000332

Does longer-muscle length resistance training cause ... Our results suggest that both muscle size and fascicle length increases may be greater following LML-RT versus SML-RT, suggesting LML-RT may lead to greater ...

3. journal.iusca.org journal.iusca.org/index.php/Journal/article/view/182

Partial Vs Full Range of Motion Resistance Training Our results suggest that using a full or long ROM may enhance results for most outcomes (strength, speed, power, muscle size, and body composition).

4. frontiersin.org frontiersin.org/journals/sports-and-active-living/articles/10.3389/fspor.2022.949021/full

Resistance Training Variables for Optimization of Muscle ... This umbrella review aimed to analyze the different variables of resistance training and their effect on hypertrophy, and to provide practical recommendations.

5. bjsm.bmj.com bjsm.bmj.com/content/57/18/1211

a systematic review and Bayesian network meta-analysis All RTxs were superior to CTRL for muscle strength and hypertrophy. Higher-load (>80% of single repetition maximum) prescriptions maximised strength gains.

6. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC10579494/

Resistance training prescription for muscle strength and ... All RTxs were superior to CTRL for muscle strength and hypertrophy. Higher-load (>80% of single repetition maximum) prescriptions maximised strength gains.

7. mdpi.com mdpi.com/2411-5142/9/1/9

Optimizing Resistance Training Technique to Maximize ... Regimented resistance training (RT) has been shown to promote increases in muscle size (also known as hypertrophy) [1]. Maximizing muscle hypertrophy requires ...

8. sciencedirect.com sciencedirect.com/science/article/pii/S2095254623000601

The influence of resistance exercise training prescription ... Compared with a non-exercising control group, resistance training consistently improved muscle mass, strength and physical function. •. Resistance training ...

9. 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.

10. bjsm.bmj.com bjsm.bmj.com/content/52/6/376

A systematic review, meta-analysis and meta-regression ... Dietary protein supplementation significantly enhanced changes in muscle strength and size during prolonged RET in healthy adults.