Determining the Effect of Muscle Length At Peak Force on Resistance Training Induced Hypertrophy
试验速览
- 阶段
- 不适用
- 状态
- Enrolling By Invitation
- 入组人数
- 20
- 试验地点
- 1
- 主要终点
- Muscle Volume
研究概览
简要总结
The goal of this clinical trial is to learn the effect of applying peak force/resistance to skeletal muscles during resistance exercise training in young and healthy adults. Participants will undergo two types of resistance training conditions that are randomly assigned to the left arm and leg and the right arm and leg. The LONG condition refers to Prime Fitness machines set to setting number '3' which applies peak force at a long muscle length. The SHORT condition refers to Prime Fitness machines set to setting number '2' which applies peak force at a short muscle length.
The main questions the trial aims to answer are:
- Does applying peak force at a longer or shorter muscle length during resistance exercise training result in greater muscle growth?
- Does applying peak force at a longer or shorter muscle length during resistance exercise training result in greater muscle growth?
We hypothesize that:
- LONG will induce greater hypertrophy compared to SHORT conditions
- LONG will result in greater increases in 1RM strength compared to SHORT
- LONG and SHORT training will result in angle specific increases in isokinetic strength
- Muscle oxygenation will decline to a greater degree during LONG compared to SHORT exercise and this will be maintained between weeks 1 and 12 of training
The investigators will compare the change in muscle volume and muscular strength between the LONG and SHORT training conditions, which each participant will have the left arm and leg as well as the right arm and leg randomly assigned to either exclusively LONG or SHORT conditions.
Participants will:
- Resistance train the left and right arm and leg with two separate conditions; LONG and SHORT for 12 weeks, with the first and last weeks dedicated to only strength testing (Isotonic and Isokinetic) and measuring muscle volume via magnetic resonance imaging (MRI)
- Visit the gym for resistance training 2 times per week
- Visit the UBC MRI Research Facility in weeks 1 and 12 for MRI of muscle volume
详细描述
Statistical Analysis
Null Hypothesis Significance Testing (NHST) will be used to measure differences in hypertrophy, differences in 1RM strength, Isokinetic strength and muscle oxygenation between LONG and SHORT conditions.
It is anticipated that this study will require at least 20 participants to be screened and registered into the trial. Data will be analyzed on the basis that all participants will be included in the analysis. Participants who drop out (withdraw from treatment) will be followed up with to collect all available data and will not be replaced. Missing data will be assumed missing at random.
Sample Size Calculation:
Based on the effect size reported by Maeo et al. (2023) for difference in triceps brachia long head hypertrophy between training performed in the lengthened compared to shortened position using a within participant design, (d=0.61) a sample size of 20 participants was calculated to achieve an a priori power of 90%.
研究设计
- 研究类型
- Interventional
- 分配方式
- Na
- 干预模型
- Single Group
- 主要目的
- Other
- 盲法
- None
入排标准
- 年龄范围
- 19 Years 至 30 Years（Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Able to understand and communicate in English
- •19-30 years of age
- •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)
排除标准
- •BMI lower than 18 or greater than 30
- •Difficulty to understand and communicate in English
- •Current use of cigarettes or other nicotine devices
- •Any major uncontrolled cardiovascular, muscular, metabolic, and/or neurological disorders
- •Any medical condition impacting the ability to participate in maximal exercise
- •Type one or type two diabetes
- •Diagnosis of cancer or undergoing cancer treatment in the past 12 months
- •Drug therapy with any drugs that alter skeletal muscle metabolism (i.e., Metformin, Benzodiazepines)
- •Omega-3 (EPA, DHA, fish oil) supplementation within the previous 6 weeks
- •Implants containing ferrous metal
- •Surgery or tattoos (including tattooed eyeliner) in the last 6 weeks
研究组 & 干预措施
SHORT and LONG Training Protocol
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.
干预措施: LONG and SHORT Resistance Training (Other)
SHORT and LONG Training Protocol
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.
干预措施: Maximal Isotonic Strength Testing (1RM) (Other)
SHORT and LONG Training Protocol
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.
干预措施: Isokinetic Strength Testing (Other)
SHORT and LONG Training Protocol
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.
干预措施: Muscle Oxygenation (Other)
结局指标
主要结局
Muscle Volume
时间窗: From enrolment to the end of the intervention at 12 weeks
Muscle volume of the pectoralis major, deltoid and gluteus maximus muscle will be measured by cross sectional area (CSA) via Magnetic Resonance Imaging (MRI). The entire muscle length will be imaged and images at 25%, 50% and 75% of the entire muscle length will be analyzed to calculate CSA and any regional differences in hypertrophy.
次要结局
- Isotonic Strength testing(Initial testing in week 1 and final testing in week 12)
- Isokinetic Strength Testing(Initial testing in week 1 and final testing in week 12)
- Muscle Oxygenation(Week 2 and week 11.)
研究者
Cameron Mitchell
Principal Investigator
University of British Columbia