Flywheel vs Traditional Resistance Training for Change of Direction in Elite Soccer Players

NCT07567677 | Completed

• 1 other identifier: BSU2025611H-FRTCOD
• Study Type: interventional
• Target: 22
• Locations: 1 country
• Sites: 1

Brief Summary

The purpose of this randomized controlled trial is to compare the effects of unilateral flywheel resistance training and unilateral traditional resistance training on change-of-direction performance in elite male soccer players. A total of 22 elite soccer players will be randomly assigned to either a flywheel resistance training group or a traditional resistance training group. Both groups will perform supervised training twice per week for 8 weeks in addition to their regular soccer training. Performance outcomes will include linear sprint tests (10 m and 30 m), pre-planned change-of-direction tests (Pro-agility, T-test, Arrowhead test), and agility tests under no-ball and with-ball conditions (AFL agility test). The primary outcome is change-of-direction performance assessed by the T-test. Secondary outcomes include direction-specific change-of-direction ability and agility performance. It is hypothesized that unilateral flywheel resistance training will produce greater improvements in change-of-direction performance compared with traditional resistance training, particularly in tasks involving braking and re-acceleration.

Conditions

Change of Direction Performance; Athletic Performance

Keywords

soccer players; flywheel training; unilateral resistance training; change-of-direction speed; eccentric overload; agility performance

Outcome Measures

Primary Outcomes (1)

• T-test performance (change in completion time, seconds)

  Change in T-test completion time (seconds) from baseline to post-intervention after 8 weeks of training. The T-test assesses multidirectional change-of-direction ability involving forward sprinting, lateral shuffling, and backward running.

  Baseline and Week 8

Study Arms (2)

Flywheel Resistance Training

EXPERIMENTAL

Participants perform unilateral flywheel resistance training using a Bulgarian split squat exercise twice per week for 8 weeks in addition to regular soccer training.

Other: Flywheel Resistance Training

Traditional Resistance Training

ACTIVE COMPARATOR

Participants perform unilateral traditional resistance training using a barbell Bulgarian split squat exercise twice per week for 8 weeks in addition to regular soccer training.

Other: Traditional Resistance Training

Interventions

Flywheel Resistance Training OTHER

Unilateral flywheel resistance training was performed using a Bulgarian split squat exercise on a flywheel device. Participants completed 2 training sessions per week for 8 weeks. Each session consisted of 4 sets of 6 repetitions per leg. The inertial load was individually selected based on mean concentric velocity matching. Participants were instructed to perform the concentric phase explosively and the eccentric phase with maximal braking effort.

Also known as: Flywheel training Isoinertial training

Flywheel Resistance Training

Traditional Resistance Training OTHER

Unilateral traditional resistance training was performed using a barbell Bulgarian split squat exercise. Participants trained twice per week for 8 weeks. Each session consisted of 4 sets of 6 repetitions per leg at approximately 80% of one-repetition maximum. Movement tempo was controlled with an explosive concentric phase and a controlled eccentric phase.

Traditional Resistance Training

Eligibility Criteria

• Age: 18 Years - 25 Years
• Sex: male
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Male elite or sub-elite soccer players aged 18-25 years
• Minimum of 3 years of structured soccer training experience
• Currently participating in regular team training (≥3 sessions per week)
• Free from musculoskeletal injury within the past 3 months
• No prior experience with flywheel resistance training
• Provided written informed consent to participate

You may not qualify if:

• History of lower-limb surgery within the past 6 months
• Current musculoskeletal pain or injury affecting performance
• Neurological or cardiovascular conditions contraindicating high-intensity exercise
• Participation in additional strength or conditioning programs outside the study
• Inability to complete the full intervention protocol

Sponsors & Collaborators

• Beijing Sport University: lead

Study Sites (1)

Beijing Sport University

Beijing, 100084, China

Location

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: OUTCOMES ASSESSOR
• Masking Details: Outcome assessors were blinded to group allocation during performance testing and data collection.
• Purpose: BASIC SCIENCE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Graduate Student

Model Details: Participants are randomly assigned to two parallel groups: a flywheel resistance training group and a traditional resistance training group. Both groups perform the intervention concurrently over 8 weeks, with matched training structure and movement patterns.

Study Record Dates

• First Submitted: April 28, 2026
• First Posted: May 5, 2026
• Study Start: February 20, 2026
• Primary Completion: April 20, 2026
• Study Completion: April 21, 2026
• Last Updated: May 5, 2026

Record last verified: 2026-04

Data Sharing

• IPD Sharing: Will not share

Locations

CN (1)