High- and Low-Load Resistance Training to Failure Result in Similar Muscular Adaptations in Untrained Young Males
Overview
- Phase
- Not Applicable
- Status
- Completed
- Sponsor
- Akdeniz University
- Enrollment
- 22
- Locations
- 1
- Primary Endpoint
- Maximal Dynamic Strength - Estimated One-Repetition Maximum (1RM) Using Submaximal Prediction and Epley Equation
Overview
Brief Summary
The goal of this clinical trial is to learn whether low-load resistance training performed to muscle failure can produce similar increases in muscle size and strength as high-load resistance training in healthy untrained young adult males.
The main questions it aims to answer are:
Does low-load resistance training (30% of one-repetition maximum) performed to failure increase muscle strength and muscle size to a similar extent as high-load resistance training (75% of one-repetition maximum)?
Are there differences in total training volume between low-load and high-load resistance training programs performed to failure?
Researchers will compare a low-load resistance training group to a high-load resistance training group to determine whether the magnitude of changes in muscle strength and hypertrophy differs between the two approaches.
Participants will:
Be randomly assigned to either a low-load (30% 1RM) or high-load (75% 1RM) resistance training group
Perform supervised leg extension exercises to the point of voluntary muscle fatigue three times per week for 6 weeks
Complete muscle strength testing (one-repetition maximum) before and after the training period
Undergo ultrasound measurements to assess muscle thickness and cross-sectional area of thigh muscles before and after the intervention
Study Design
- Study Type
- Interventional
- Allocation
- Randomized
- Intervention Model
- Parallel
- Primary Purpose
- Other
- Masking
- Single (Investigator)
Eligibility Criteria
- Ages
- 18 Years to 28 Years (Adult)
- Sex
- Male
- Accepts Healthy Volunteers
- Yes
Inclusion Criteria
- •Age between 18 and 28 years
- •Healthy status as determined by self-report health screening
- •No participation in structured resistance training or lower-limb power training within the previous 12 months
- •Engaging only in recreational physical activity (no systematic lower-body resistance training)
- •Willingness to maintain usual daily routines throughout the study period
- •Agreement to refrain from any structured lower-body resistance training during the 6-week intervention
- •Provision of written informed consent
Exclusion Criteria
- •Any current or recent musculoskeletal injury affecting lower-limb function
- •History or presence of cardiovascular disease
- •History or presence of metabolic disorders
- •Resting hypertension (≥140/90 mmHg)
- •Regular tobacco use
- •Use of medications known to affect neuromuscular performance
- •Inability or unwillingness to comply with the training protocol
Arms & Interventions
LLRT
Intervention: Low-load resistance training (30% 1RM) (Other)
HLRT
Intervention: High-load resistance training (75% 1RM) (Other)
Outcomes
Primary Outcomes
Maximal Dynamic Strength - Estimated One-Repetition Maximum (1RM) Using Submaximal Prediction and Epley Equation
Time Frame: Baseline (Week 0) and immediately after completion of the 6-week intervention (Week 6)
Maximal strength will be estimated using a submaximal 1RM prediction protocol (8-10 repetitions) following a standardized warm-up. The highest load completed within the target repetition range will be used to calculate 1RM using the Epley equation (1RM = Load × \[1 + 0.033 × repetitions\]). Results will be expressed in kilograms (kg), with higher values indicating greater strength. Assessed at baseline and Week 4.
Muscle Thickness (MT) and Cross-Sectional Area (CSA) - Assessed by B-Mode Ultrasonography (LOGIQ S8, GE Healthcare)
Time Frame: Baseline (Week 0) and immediately after completion of the 6-week intervention (Week 6)
Muscle thickness (cm) and cross-sectional area (cm²) of the rectus femoris and vastus intermedius will be assessed using B-mode ultrasonography (LOGIQ S8, GE Healthcare, 2-8 MHz linear probe). Three images per site will be averaged for analysis. Higher values indicate greater muscle hypertrophy. Measurements performed at baseline and post-intervention by a blinded assessor.
Secondary Outcomes
- Muscular Endurance - Repetitions to Volitional Failure at 50% of Estimated 1RM(Baseline (Week 0) and immediately after completion of the 6-week intervention (Week 6))
Investigators
Abdullah Kayhan
Research Assistant
Akdeniz University