Chronic Ankle InstabilityNCT07134829
The Effects of Stroboscopic Visual Conditions on Gait and Lower Limb Muscle Activity in Individuals With Chronic Ankle Instability
A study testing Stroboscopic Visual Conditions in people with Chronic Ankle Instability, run by Sahmyook University at 1 site in South Korea.
Trial summary
This interventional study will investigate the effects of stroboscopic visual conditions on gait patterns and lower limb muscle activation in adults with chronic ankle instability (CAI). Read more about this study
- Who is it for?
- Ages 18 to 45 years
- Conditions the study is for
- Chronic Ankle Instability
- What is being tested?
- Stroboscopic Visual Conditions
- Type of treatment
- Lifestyle or therapy programme
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 25 participants
- Where
- 1 siteSouth Korea
- Study dates
- 31 Aug 2025to 12 Oct 2025
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 45 years
- All sexes
- No healthy volunteers
- Adult
Who may be able to join
- Individuals with a Cumberland Ankle Instability Tool (CAIT) score of less than 24
- Individuals diagnosed with ankle sprain or instability within the past 6 months
Who cannot join
- Individuals who have undergone lower limb surgery or experienced a fracture due to ankle trauma within the past 6 months
- Individuals with systemic diseases, such as cardiovascular disorders, that may affect balance
- Individuals who have difficulty understanding or following instructions during assessment or training
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
South Korea1 site
Sahmyook University
Seoul, 01795
Suhyeon Jeong, MSc Candidate, +82-10-4510-9276, jsh9276@naver.com
Suhyeon Jeong, MSc Candidate
About this study
This interventional study will investigate the effects of stroboscopic visual conditions on gait patterns and lower limb muscle activation in adults with chronic ankle instability (CAI). CAI often results in impaired sensorimotor control, leading to altered gait strategies such as slower walking speed, shorter step length, and increased visual reliance. Stroboscopic glasses intermittently restrict visual input, potentially reducing visual dependence and enhancing proprioceptive feedback.
Participants will complete walking trials under three randomized visual conditions: high-frequency stroboscopic, low-frequency stroboscopic, and no-glasses control. Gait parameters will be measured using the GAITRite system, and surface electromyography (sEMG) will record activation of the tibialis anterior, peroneus longus, and gastrocnemius muscles. Findings may provide insight into sensorimotor adaptation mechanisms and inform rehabilitation strategies to improve functional stability in individuals with CAI.
Read the detailed description
Chronic ankle instability (CAI) is a frequent outcome after ankle sprains, characterized by recurrent giving-way episodes, pain, and functional limitations. Approximately 40% of individuals with ankle sprains develop CAI, which is associated with deficits in proprioception, neuromuscular coordination, and postural stability. Increased visual reliance is a common compensatory strategy, but this can impair balance and gait when visual input is limited, raising the risk of re-injury.
Stroboscopic glasses alternate between transparent and opaque states, intermittently restricting visual information. This challenges the sensorimotor system, potentially reducing visual dependence and enhancing proprioceptive engagement. Prior research has shown benefits for static and dynamic balance, but little is known about effects on walking in CAI populations.
This randomized crossover study will assess the impact of high-frequency and low-frequency stroboscopic visual conditions compared with normal vision on gait and lower limb muscle activation in CAI. Adults aged 18-45 years with CAIT scores < 24 and a history of ankle instability within 6 months will be recruited. Exclusion criteria include recent lower limb surgery/fracture, systemic conditions affecting balance, or inability to follow instructions.
Participants will perform walking trials on a 5-meter GAITRite walkway under three randomized visual conditions:
- High-frequency stroboscopic (rapid alternation)
- Low-frequency stroboscopic (slower alternation)
- No-glasses control (normal vision)
Gait parameters (step length, step time, gait velocity, swing/stance phases) will be measured, and sEMG (Noraxon) will assess activation of the tibialis anterior, peroneus longus, and gastrocnemius, normalized to MVIC. Subjective measures include CAIT, FAAM, IdFAI, and VAS pain scores.
It is hypothesized that stroboscopic conditions will produce measurable changes in gait and muscle activity compared with control, reflecting adaptive sensorimotor strategies that can inform rehabilitation programs to improve stability, mobility, and reduce re-injury risk.
- Conditions
- Chronic Ankle Instability
- Being tested
- Stroboscopic Visual Conditions
- Keywords
- Stroboscopic Glasses, Stroboscopic Vision, Gait Analysis, Surface Electromyography
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Stroboscopic Visual ConditionsBehavioural
Participants will perform walking trials under three visual conditions: high-frequency stroboscopic glasses, low-frequency stroboscopic glasses, and no-glasses control. Each participant will complete three 5-meter walking trials per condition, with the order of conditions randomized. Gait parameters will be recorded using the GAITRite walkway system, and muscle activity will be measured using surface electromyography.
| Study group | Role | What they receive |
|---|---|---|
| Single Group - Chronic Ankle Instability | Experimental | All participants with chronic ankle instability will complete walking trials under three visual conditions: high-frequency stroboscopic glasses, low-frequency stroboscopic glasses, and no-glasses control. Each participant will perform three 5-meter walking trials per condition, with the order of conditions randomized. Receives: Behavioral: Stroboscopic Visual Conditions |
What is being measured
The primary outcome is the main question the study is designed to answer.
Change in Gait Velocity (cm/s) Under Different Stroboscopic Visual Conditions
Gait velocity will be measured using the GAITRite system under three visual conditions: high-frequency stroboscopic, low-frequency stroboscopic, and no stroboscopic. Each participant will perform three walking trials per condition over a 5-meter walkway. The average gait velocity (cm/s) will be calculated for each condition.
Measured: Day 1 (single experimental session; immediately after each walking condition)
Secondary outcomes (12)
Change in Step Length (cm) Under Different Stroboscopic Visual Conditions
Step length will be measured using the GAITRite system under three visual conditions. The average value (cm) will be calculated for each condition.
Measured: Day 1 (single experimental session; immediately after each walking condition)
Change in Step Width (cm) Under Different Stroboscopic Visual Conditions
Step width will be measured using the GAITRite system under three visual conditions.
Measured: Day 1 (single experimental session; immediately after each walking condition)
Change in Swing Phase (%) Under Different Stroboscopic Visual Conditions
Swing phase duration as a percentage of the gait cycle will be measured using the GAITRite system under three visual conditions.
Measured: Day 1 (single experimental session; immediately after each walking condition)
Change in Single Limb Support (%) Under Different Stroboscopic Visual Conditions
Single limb support duration as a percentage of the gait cycle will be measured.
Measured: Day 1 (single experimental session; immediately after each walking condition)
Change in Double Limb Support (%) Under Different Stroboscopic Visual Conditions
Double limb support duration as a percentage of the gait cycle will be measured.
Measured: Day 1 (single experimental session; immediately after each walking condition)
Change in Tibialis Anterior Muscle Activation (%MVIC) Under Different Stroboscopic Visual Conditions
Surface electromyography (sEMG) will measure tibialis anterior muscle activation during walking. Data will be normalized to maximum voluntary isometric contraction (%MVIC).
Measured: Day 1 (single experimental session; immediately after each walking condition)
Change in Peroneus Longus Muscle Activation (%MVIC) Under Different Stroboscopic Visual Conditions
sEMG will measure peroneus longus muscle activation during walking, normalized to %MVIC.
Measured: Day 1 (single experimental session; immediately after each walking condition)
Change in Gastrocnemius Muscle Activation (%MVIC) Under Different Stroboscopic Visual Conditions
sEMG will measure gastrocnemius muscle activation during walking, normalized to %MVIC.
Measured: Day 1 (single experimental session; immediately after each walking condition)
Correlation Between Foot and Ankle Ability Measure - ADL Subscale (FAAM-ADL) Score and Gait Velocity (cm/s)
Pearson's correlation will be computed between FAAM-ADL score (0-100; higher scores indicate better function) and gait velocity.
Measured: Day 1 (questionnaire administered before walking tasks)
Correlation Between Foot and Ankle Ability Measure - Sports Subscale (FAAM-Sports) Score and Gait Velocity (cm/s)
Pearson's correlation will be computed between FAAM-Sports score (0-100; higher scores indicate better function) and gait velocity.
Measured: Day 1 (questionnaire administered before walking tasks)
Correlation Between Identification of Functional Ankle Instability (IdFAI) Score and Gait Velocity (cm/s)
Pearson's correlation will be computed between IdFAI score (0-30; higher scores indicate greater instability) and gait velocity.
Measured: Day 1 (questionnaire administered before walking tasks)
Correlation Between Visual Analogue Scale (VAS) Pain Score and Gait Velocity (cm/s)
Pearson's correlation will be computed between VAS pain score (0-10; higher scores indicate more severe pain) and gait velocity.
Measured: Day 1 (questionnaire administered before walking tasks)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted21 Aug 2025
- Study start31 Aug 2025 (estimated)
- Primary completion28 Sep 2025 (estimated)
- Study completion12 Oct 2025 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Chronic Ankle InstabilityStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Basic science
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 25 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Sahmyook University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Suhyeon Jeong, Sahmyook University
- Investigators
- Seungwon Lee, PhD, Principal investigator, Sahmyook University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07134829
- Sponsor's protocol ID
- SYU 2025-06-026-002
- Status last verified
- Aug 2025
- First submitted
- 9 Aug 2025
- Last updated
- 21 Aug 2025
- Results posted
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 21 Aug 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- The Effects of Stroboscopic Visual Conditions on Gait and Lower Limb Muscle Activity in Individuals With Chronic Ankle Instability
- ClinicalTrials.gov ID
- NCT07134829
- Acronym / sponsor ID
- SYU 2025-06-026-002
- Conditions
- Chronic Ankle Instability
- Keywords
- Stroboscopic Glasses, Stroboscopic Vision, Gait Analysis, Surface Electromyography
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 25 participants (estimated)
- Lead sponsor
- Sahmyook UniversityUniversity, hospital or other
- Study start
- 31 Aug 2025 (estimated)
- Primary completion
- 28 Sep 2025 (estimated)
- Study completion
- 12 Oct 2025 (estimated)
- First posted
- 21 Aug 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This interventional study will investigate the effects of stroboscopic visual conditions on gait patterns and lower limb muscle activation in adults with chronic ankle instability (CAI). CAI often results in impaired sensorimotor control, leading to altered gait strategies such as slower walking speed, shorter step length, and increased visual reliance. Stroboscopic glasses intermittently restrict visual input, potentially reducing visual dependence and enhancing proprioceptive feedback.
Participants will complete walking trials under three randomized visual conditions: high-frequency stroboscopic, low-frequency stroboscopic, and no-glasses control. Gait parameters will be measured using the GAITRite system, and surface electromyography (sEMG) will record activation of the tibialis anterior, peroneus longus, and gastrocnemius muscles. Findings may provide insight into sensorimotor adaptation mechanisms and inform rehabilitation strategies to improve functional stability in individuals with CAI.
Detailed description
Chronic ankle instability (CAI) is a frequent outcome after ankle sprains, characterized by recurrent giving-way episodes, pain, and functional limitations. Approximately 40% of individuals with ankle sprains develop CAI, which is associated with deficits in proprioception, neuromuscular coordination, and postural stability. Increased visual reliance is a common compensatory strategy, but this can impair balance and gait when visual input is limited, raising the risk of re-injury.
Stroboscopic glasses alternate between transparent and opaque states, intermittently restricting visual information. This challenges the sensorimotor system, potentially reducing visual dependence and enhancing proprioceptive engagement. Prior research has shown benefits for static and dynamic balance, but little is known about effects on walking in CAI populations.
This randomized crossover study will assess the impact of high-frequency and low-frequency stroboscopic visual conditions compared with normal vision on gait and lower limb muscle activation in CAI. Adults aged 18-45 years with CAIT scores < 24 and a history of ankle instability within 6 months will be recruited. Exclusion criteria include recent lower limb surgery/fracture, systemic conditions affecting balance, or inability to follow instructions.
Participants will perform walking trials on a 5-meter GAITRite walkway under three randomized visual conditions:
- High-frequency stroboscopic (rapid alternation)
- Low-frequency stroboscopic (slower alternation)
- No-glasses control (normal vision)
Gait parameters (step length, step time, gait velocity, swing/stance phases) will be measured, and sEMG (Noraxon) will assess activation of the tibialis anterior, peroneus longus, and gastrocnemius, normalized to MVIC. Subjective measures include CAIT, FAAM, IdFAI, and VAS pain scores.
It is hypothesized that stroboscopic conditions will produce measurable changes in gait and muscle activity compared with control, reflecting adaptive sensorimotor strategies that can inform rehabilitation programs to improve stability, mobility, and reduce re-injury risk.
Study design
- Primary purpose
- Basic science
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Single Group - Chronic Ankle Instability | Experimental | Behavioral: Stroboscopic Visual ConditionsAll participants with chronic ankle instability will complete walking trials under three visual conditions: high-frequency stroboscopic glasses, low-frequency stroboscopic glasses, and no-glasses control. Each participant will perform three 5-meter walking trials per condition, with the order of conditions randomized. |
Who may qualify
- Ages
- 18 to 45 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult
Key inclusion criteria (2 listed)
- Individuals with a Cumberland Ankle Instability Tool (CAIT) score of less than 24
- Individuals diagnosed with ankle sprain or instability within the past 6 months
Key exclusion criteria (3 listed)
- Individuals who have undergone lower limb surgery or experienced a fracture due to ankle trauma within the past 6 months
- Individuals with systemic diseases, such as cardiovascular disorders, that may affect balance
- Individuals who have difficulty understanding or following instructions during assessment or training
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Stroboscopic Visual ConditionsParticipants will perform walking trials under three visual conditions: high-frequency stroboscopic glasses, low-frequency stroboscopic glasses, and no-glasses control. Each participant will complete three 5-meter walking trials per condition, with the order of conditions randomized. Gait parameters will be recorded using the GAITRite walkway system, and muscle activity will be measured using surface electromyography. | Behavioural | Single Group - Chronic Ankle Instability |
Primary outcome
Change in Gait Velocity (cm/s) Under Different Stroboscopic Visual Conditions
Time frame: Day 1 (single experimental session; immediately after each walking condition)
Gait velocity will be measured using the GAITRite system under three visual conditions: high-frequency stroboscopic, low-frequency stroboscopic, and no stroboscopic. Each participant will perform three walking trials per condition over a 5-meter walkway. The average gait velocity (cm/s) will be calculated for each condition.
12 secondary outcomes
Change in Step Length (cm) Under Different Stroboscopic Visual Conditions
Time frame: Day 1 (single experimental session; immediately after each walking condition)
Change in Step Width (cm) Under Different Stroboscopic Visual Conditions
Time frame: Day 1 (single experimental session; immediately after each walking condition)
Change in Swing Phase (%) Under Different Stroboscopic Visual Conditions
Time frame: Day 1 (single experimental session; immediately after each walking condition)
Change in Single Limb Support (%) Under Different Stroboscopic Visual Conditions
Time frame: Day 1 (single experimental session; immediately after each walking condition)
Change in Double Limb Support (%) Under Different Stroboscopic Visual Conditions
Time frame: Day 1 (single experimental session; immediately after each walking condition)
Change in Tibialis Anterior Muscle Activation (%MVIC) Under Different Stroboscopic Visual Conditions
Time frame: Day 1 (single experimental session; immediately after each walking condition)
Change in Peroneus Longus Muscle Activation (%MVIC) Under Different Stroboscopic Visual Conditions
Time frame: Day 1 (single experimental session; immediately after each walking condition)
Change in Gastrocnemius Muscle Activation (%MVIC) Under Different Stroboscopic Visual Conditions
Time frame: Day 1 (single experimental session; immediately after each walking condition)
Correlation Between Foot and Ankle Ability Measure - ADL Subscale (FAAM-ADL) Score and Gait Velocity (cm/s)
Time frame: Day 1 (questionnaire administered before walking tasks)
Correlation Between Foot and Ankle Ability Measure - Sports Subscale (FAAM-Sports) Score and Gait Velocity (cm/s)
Time frame: Day 1 (questionnaire administered before walking tasks)
Correlation Between Identification of Functional Ankle Instability (IdFAI) Score and Gait Velocity (cm/s)
Time frame: Day 1 (questionnaire administered before walking tasks)
Correlation Between Visual Analogue Scale (VAS) Pain Score and Gait Velocity (cm/s)
Time frame: Day 1 (questionnaire administered before walking tasks)
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 21 Aug 2025.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Seungwon Lee, PhD principal investigator
Sahmyook University
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Stroboscopic Visual Conditions in people with Chronic Ankle Instability, run by Sahmyook University at 1 site in South Korea.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 2 inclusion and 3 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: opening soon, as of the sponsor's last update on 21 Aug 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in South Korea. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Suhyeon Jeong, MSc Candidate (+82-10-4510-9276, jsh9276@naver.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Change in Gait Velocity (cm/s) Under Different Stroboscopic Visual Conditions (time frame: Day 1 (single experimental session; immediately after each walking condition)). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 21 Aug 2025.