Effects of Deloading Periods in Resistance Training on Muscular Strength and Hypertrophy

Not Applicable

Completed

• Conditions: Muscle Hypertrophy in Healthy Young Men

• Registration Number: NCT06825052
• Lead Sponsor: University of Gaziantep

Brief Summary

This study investigates the effects of deloading periods (short breaks or reductions in training volume) in a 8-week resistance training program on muscle strength and hypertrophy in young, untrained individuals.

Participants were randomly assigned to two training conditions:

Deload Training Group: Reduced training volume for one week every four weeks. Continuous Training Group: Regular training without reductions. Muscle thickness was measured using ultrasound, and muscle strength was evaluated through a 10-repetition maximum (10RM) test before and after the intervention.

The findings showed that both training strategies led to significant increases in muscle strength and size, with no major differences between groups. This suggests that incorporating deloading periods does not negatively impact muscle development and may serve as an effective alternative for individuals with time constraints or minor injuries.

This study was conducted at Gaziantep University, Faculty of Sports Sciences, with approval from the university's ethics committee.

Detailed Description

This study examines the effects of deloading periods (planned reductions in training volume and frequency) within an 8-week resistance training program on muscle hypertrophy and strength in untrained young individuals.

The study utilized a randomized within-subject design, where each participant's limbs were assigned to one of two conditions:

Deload Training Condition: Training volume and frequency were reduced during Weeks 4 and 8 to allow for recovery.

Continuous Training Condition: No reductions in training volume were applied. The resistance training program included unilateral leg extension and unilateral dumbbell biceps curl exercises performed twice per week. The training intensity was adjusted to ensure participants reached voluntary muscular failure within the 8-12 repetition range.

Assessments \& Measurements:

Muscle Hypertrophy: Measured using B-mode ultrasound at different quadriceps and biceps locations.

Muscle Strength: Evaluated through 10-repetition maximum (10RM) testing before and after the intervention.

Statistical Analysis: A 2-way repeated-measures ANOVA was used to compare training conditions, with effect sizes analyzed to determine the significance of adaptations.

The study was approved by the Gaziantep University Health and Sports Sciences Ethics Committee and conducted in accordance with the Declaration of Helsinki guidelines.

Study Timeline

• Study Start: 2024-05-01
• Primary Completion: 2024-06-25
• Study Completion: 2024-08-20
• Status Verified: 2025-02
• Study First Submitted: 2025-02-04
• Study First Submitted QC: 2025-02-07
• Last Update Submitted: 2025-02-07
• Study First Posted: 2025-02-13
• Last Update Posted: 2025-02-13

Recruitment & Eligibility

• Status: COMPLETED
• Sex: Male
• Target Recruitment: 19

Inclusion Criteria

• Healthy, untrained individuals (no prior structured resistance training experience for at least 6 months).
• Aged between 18-25 years old.
• No current or recent musculoskeletal injuries affecting exercise performance.
• No diagnosed medical conditions that could interfere with resistance training.
• Willing to participate in an 8-week structured resistance training program.
• No use of performance-enhancing drugs, anabolic steroids, or other muscle-growth supplements.

Exclusion Criteria

• Individuals with prior resistance training experience within the last 6 months.
• Any current or past musculoskeletal injuries or conditions affecting the lower or upper limbs.
• Any diagnosed metabolic, cardiovascular, or neurological disorders that could affect physical performance.
• Individuals currently taking medications that affect muscle function or recovery.
• Pregnant or breastfeeding individuals.
• Failure to comply with the study protocol (e.g., missing more than 2 training sessions).

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Primary Outcome Measures

Name	Time	Method
Muscular Strength	Baseline and after 8 weeks	Changes in muscle strength will be assessed using 10-repetition maximum (10RM) testing before and after the intervention. Strength assessments will be conducted for both the quadriceps (leg extension) and biceps brachii (dumbbell curl).

Secondary Outcome Measures

Name	Time	Method
Muscle Hypertrophy	Baseline and after 8 weeks	Changes in muscle thickness will be measured using B-mode ultrasound imaging. Measurements will be taken at multiple anatomical points on the quadriceps and biceps brachii muscles before and after the intervention.

Trial Locations

Locations (1)

Gaziantep University, Faculty of Sport Sciences; 🇹🇷 Gaziantep, Şehitkamil, Turkey