External Focus of Attention Feedback to Reduce Risk of Non-contact ACL Injury

June 1, 2026 updated by: Abbey Thomas, PhD, University of North Carolina, Charlotte
Knee injuries, especially those to the ACL, are common among physically active people. Preventing these injuries from happening is critical to limiting the long-term pain, disability, and arthritis associated with these injuries. Our study is going to examine new ways to provide feedback about the way people move to determine if these are better at modifying movement patterns to prevent injury than current standard treatments. If you participate, you will be asked to undergo a movement analysis in a research laboratory while you perform tasks such as landing from a box and running and cutting. After this initial assessment, you will be randomly allocated to one of 3 treatment groups. Each treatment group will perform 4 weeks (3x/week) of exercises to change the way people land from a jump. Participants will then report for follow-up movement analysis testing 1- and 4-weeks after completing the intervention.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Detailed Description

Despite the popularity of injury prevention programs, anterior cruciate ligament (ACL) injuries continue to occur at a rate of 250,000 per year in the United States. It is believed that 75% of these injuries are preventable, thus alternative strategies to reduce the risk of injury are necessary. One reason current prevention strategies are not wholly successful may be their reliance on internal focus of attention (InFOCUS) feedback, which constrains movement and increases injury risk. Our project will examine an alternative approach, testing two different modes of external focus of attention (ExFOCUS) feedback to remove constrains on the way people move to reduce injury risk. We will also examine cortical activity to determine if there are differences in neuroplasticity that occur following each form of feedback to better understand how each works. Collectively, the knowledge gained from this study will inform the development of programs to reduce injury risk.

Specific Aim 1: Determine ExFOCUS's ability to reduce the risk of noncontact ACL injury by retaining improved biomechanics compared to InFOCUS. Hypothesis 1.1: the combined auditory and visual ExFOCUS groups will demonstrate greater improvements in biomechanics and will retain these improvements 1 month after cessation of the intervention.

Specific Aim 2: Determine differences in the ability of the two modes (visual and auditory) of ExFOCUS to change biomechanics. Hypothesis 2.1: Auditory ExFOCUS feedback will elicit superior results compared to visual ExFOCUS feedback immediately following the intervention. Specific Aim 3: To quantify differences in cortical activity following external focus of attention and internal focus of attention feedback. Hypothesis 3.1: External focus of attention feedback will increase cortical activity in both groups while there will be no changes in cortical activity during internal focus of attention feedback Hypothesis 3.2: Auditory feedback will elicit greater changes in auditory regions of the brain, while visual feedback will elicit greater changes in regions of the brain responsible for processing visual information.

Study Type

Interventional

Enrollment (Actual)

45

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • United States
    • North Carolina
      • Charlotte, North Carolina, United States, 28223
        • UNC Charlotte

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years to 35 years (Adult)

Accepts Healthy Volunteers

Yes

Description

Inclusion Criteria:

  • exercise 30+ minutes 3+ days/week

Exclusion Criteria:

  • Body mass index >40 kg/m2
  • History of lower extremity fracture or surgery to either limb
  • History of ACL tear, meniscus, or collateral ligament injury at the knee to either limb
  • History of ankle sprains to either limb
  • History of musculoskeletal injury sustained in the 6 months prior to enrollment
  • History of concussion or neurological disorders that may influence electroencephalography activity
  • Visual or hearing impairments that would limit receiving the appropriate feedback
  • Inability to comprehend and repeat back directions in English
  • Current smoker

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Prevention
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Double

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Active Comparator: Internal focus of attention feedback
Participants will complete 12 sessions over 3 weeks receiving visual feedback in a mirror of their movement patterns.
Other: Internal focus of attention feedback
Participants will complete 12 sessions over a 3-week period of functional movement retraining while receiving mirror feedback. Participants will be instructed to perform each functional task in a manner that keeps their knee in line with their toes.
Experimental: Visual external focus of attention feedback
Participants will complete 12 sessions over 3 weeks receiving visual feedback of their movement patterns from a laser.
Other: Visual internal focus of attention feedback
Participants will complete 12 sessions over a 3-week period of functional movement retraining while receiving visual feedback via laser. Participants will be instructed to perform each functional task in a manner that does causes the laser to move up and down but not side-to-side.
Experimental: Auditory external focus of attention feedback
Participants will complete 12 sessions over 3 weeks receiving auditory feedback of their movement patterns.
Other: Auditory external focus of attention feedback
Participants will complete 12 sessions over a 3-week period of functional movement retraining while receiving auditory feedback. Participants will be instructed to perform each functional task in a manner that does not cause the auditory tool to elicit a noise.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Changes from baseline in lower extremity biomechanics during landing.
Time Frame: 1-week post-intervention, 4-weeks post-intervention
Hip and knee angles and loads measured via 3D biomechanics
1-week post-intervention, 4-weeks post-intervention
Differences in biomechanical changes between visual and auditory external focus of attention feedback.
Time Frame: 1-week post-intervention, 4-weeks post-intervention
Hip and knee angles and loads measured via 3D biomechanics
1-week post-intervention, 4-weeks post-intervention

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Changes from baseline in cortical activity during landing
Time Frame: 1-week post-intervention, 4-weeks post-intervention
Electroencephalography recording of cortical activity during landing
1-week post-intervention, 4-weeks post-intervention

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

University of North Carolina, Charlotte

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

August 15, 2021

Primary Completion (Actual)

February 28, 2025

Study Completion (Actual)

March 31, 2025

Study Registration Dates

First Submitted

June 3, 2021

First Submitted That Met QC Criteria

June 3, 2021

First Posted (Actual)

June 7, 2021

Study Record Updates

Last Update Posted (Actual)

June 3, 2026

Last Update Submitted That Met QC Criteria

June 1, 2026

Last Verified

June 1, 2026

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 21-0283

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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