Hamstring InjuryNCT07421570
The Effect of Capacitive and Resistive Electrical Transfer Therapy on Hamstring Injuries
A study testing T-Plus; Wintecare SA, Chiasso, Switzerland and Exercise in people with Hamstring Injury, run by Hacettepe University at 1 site in Turkey (Türkiye).
Trial summary
The goal of this clinical trial is to evaluate the effects of capacitive resistive electric transference (CRET), which is frequently used in clinics and sports clubs for professional soccer players with hamstring injuries. Read more about this study
- Who is it for?
- Ages 18 to 40 years
- Conditions the study is for
- Hamstring Injury
- What is being tested?
- T-Plus; Wintecare SA, Chiasso, Switzerland and Exercise
- Type of treatment
- Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 22 participants
- Where
- 1 siteTurkey (Türkiye)
- Study dates
- 12 Feb 2026to 13 Jul 2026
- Phase
- Interventional
- Are there results?
- None posted in the registry
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 40 years
- All sexes
- No healthy volunteers
- Adult
Who may be able to join
- History of acute onset hamstring pain.
- Grade I or II hamstring strain injury confirmed by Magnetic Resonance Imaging (MRI) within the first 5 days following the injury.
- No history of anterior cruciate ligament (ACL) reconstruction.
Who cannot join
- Presence of neurological symptoms.
- Loss of superficial sensation or skin pathologies that may prevent CRET application.
- Refusal to sign the approval form.
Trial locations and contacts
1 site in 1 country.
About this study
Official title: The Effect of Capacitive and Resistive Electrical Transfer Therapy (CRET) on the Return to Play Time in Elite Soccer Players With Hamstring Strain Injuries
The goal of this clinical trial is to evaluate the effects of capacitive resistive electric transference (CRET), which is frequently used in clinics and sports clubs for professional soccer players with hamstring injuries. The main questions it aims to answer are:
Return to sports time Treatments sessions number Muscle oxygen saturation
The investigators will administer the treatment to a experimental group to see if CRET therapy is effective. The investigators will also administer a standard rehabilitation program to both the control and experimental groups.
Participants will:
Come for treatment and evaluations 3 times a week until participants meet the criteria for returning to sports.
Read the detailed description
Hamstring injuries are the most prevalent pathology in professional football, primarily due to the demands of high-speed running. Beyond threatening athlete health, these injuries account for 12-17% of all time-loss injuries, directly impacting a team's seasonal performance. Research has shown that teams with fewer pre-season hamstring injuries achieve greater success, while the annual financial burden on clubs reaches hundreds of millions of pounds. Recent analyses of 21 years of data from the Union of European Football Associations (UEFA) Elite Club Injury Study reveal that, despite advancements in preventive strategies and training science, hamstring injury rates have not decreased but rather increased by 30% in recent years (5). Given this substantial financial cost, it is evident that current prevention and rehabilitation programs are insufficient, highlighting the need to integrate new therapeutic modalities that optimize tissue healing into clinical practice.
Capacitive and Resistive Electric Transfer (CRET) is a non-invasive electro-physical modality that generates deep endogenous hyperthermia using radiofrequency currents, typically at a stable frequency of 448 kilohertz (kHz). Recent systematic reviews highlight that this method accelerates tissue regeneration not only through its thermal effect but also via biostimulation, which enhances ion mobility by balancing cell membrane potential. By increasing the permeability of ion channels in the cell membrane, it optimizes sodium-potassium (Na/K) pump activity, thereby helping injured and depolarized cells restore their membrane potential. CRET operates through two distinct modes (capacitive and resistive) that focus energy on specific layers based on tissue resistance, allowing it to selectively increase arterial blood perfusion even in deep muscle groups. While these studies recommend CRET for muscle regeneration, there are no randomized controlled trials investigating its efficacy specifically in hamstring injury rehabilitation. Therefore, this study aims to evaluate the effects of CRET-frequently used in clinics and sports clubs-on professional football players with hamstring injuries. The investigators hypothesized that CRET would have positive effects on tissue healing during the subacute phase.
- Conditions
- Hamstring Injury
- Being tested
- T-Plus; Wintecare SA, Chiasso, Switzerland, Exercise
- Keywords
- rehabilitation, hamstring, strain
- Medical subject headings
- Sprains and Strains
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
T-Plus; Wintecare SA, Chiasso, SwitzerlandDevice
Experimental Group (Capacitive and Resistive Electrical Transfer Therapy (CRET) Therapy): In addition to the standard rehabilitation program, CRET therapy (T-Plus; Wintecare SA, Chiasso, Switzerland) will be applied at the end of each session to the experimental group.
Positioning: The athlete will be placed in a prone position, with the passive electrode placed under the quadriceps muscle and the active electrode applied in the direction of the hamstring muscle fibers using classic massage maneuvers.
Dosage and Duration: The treatment will last a total of 20 minutes, consisting of 10 minutes in resistive mode followed by 10 minutes in capacitive mode.
Intensity: The application will start at 70% intensity. If the thermal sensation reaches a level that disturbs the athlete, the intensity will be gradually reduced by 10% to achieve the maximum tolerable thermal effect.
ExerciseOther
A standard hamstring rehabilitation program consisting of three phases will be implemented.
| Study group | Role | What they receive |
|---|---|---|
| Capacitive and Resistive Electrical Transfer Therapy (CRET) experimental | Experimental | In addition to the standard rehabilitation program, the experimental group will receive Capacitive and Resistive Electrical Transfer Therapy (CRET) (T-Plus; Wintecare SA, Chiasso, Switzerland) at the end of each session. Receives: Device: T-Plus; Wintecare SA, Chiasso, Switzerland; Other: Exercise |
| Control | Active comparator | Participants in the control group will undergo a standard, evidence-based, three-stage hamstring rehabilitation program. Receives: Other: Exercise |
What is being measured
The primary outcome is the main question the study is designed to answer.
Return to Sport Time
The primary outcome measure is the number of days from the time of injury to the time when criteria for full return to sports are met.
Measured: 5 weeks
Secondary outcomes (3)
Hamstring Flexibility
Passive straight leg raise, passive knee extension at 90° hip flexion, and active knee extension at full hip flexion angles will be measured using a smartphone-based goniometer (Goniometer Plus) with proven validity and reliability.
Measured: 5 weeks
Hamstring strength
Hamstring muscle strength will be assessed using a hand dynamometer (MicroFet 2, Hoggan Health, USA). Measurements will be taken in the prone position with the knee flexed at 90°, in the form of isometric strength and mid-range eccentric strength tests, and the maximum value of 3 repetitions will be recorded.
Measured: 5 weeks
Muscle Oxygen Saturation
Muscle oxygenation in the injured area will be monitored using a non-invasive near-infrared spectroscopy (NIRS) device (Moxy Monitor, Fortiori Design LLC). The device will be secured to the injured area with adhesive tape, and the average capillary oxygen saturation (SmO2) values obtained during the 10-second measurement period will be recorded. The Moxy device has previously been shown to be valid and reliable for measuring muscle oxygenation.
Measured: 5 weeks
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted19 Feb 2026
- Study start12 Feb 2026
- Primary completion13 Jul 2026
- Study completion13 Jul 2026
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Hamstring InjuryStudies of the same condition, open and under way.
- More trials run by Hacettepe UniversityThe sponsor's other registered studies.
- 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
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- Two groups including control and experimental groups
- Masking
- Single blind
- Who is masked
- Outcomes assessor
- Enrolment
- 22 participants (actual)
Sponsor and investigators
- Lead sponsor
- Hacettepe University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Irem Duzgun, Hacettepe University
- Investigators
- Irem DUZGUN, Principal investigator, Hacettepe University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07421570
- Sponsor's protocol ID
- HU-SBE-BA-01
- Status last verified
- Feb 2026
- First submitted
- 12 Feb 2026
- Last updated
- 10 Aug 2026
- Results posted
- No
- Data monitoring committee
- Yes
- 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 10 Aug 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- The Effect of Capacitive and Resistive Electrical Transfer Therapy (CRET) on the Return to Play Time in Elite Soccer Players With Hamstring Strain Injuries
- ClinicalTrials.gov ID
- NCT07421570
- Acronym / sponsor ID
- HU-SBE-BA-01
- Conditions
- Hamstring Injury
- Keywords
- rehabilitation, hamstring, strain
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 22 participants (actual)
- Lead sponsor
- Hacettepe UniversityUniversity, hospital or other
- Study start
- 12 Feb 2026 (actual)
- Primary completion
- 13 Jul 2026 (actual)
- Study completion
- 13 Jul 2026 (actual)
- First posted
- 19 Feb 2026 (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.
The goal of this clinical trial is to evaluate the effects of capacitive resistive electric transference (CRET), which is frequently used in clinics and sports clubs for professional soccer players with hamstring injuries. The main questions it aims to answer are:
Return to sports time Treatments sessions number Muscle oxygen saturation
The investigators will administer the treatment to a experimental group to see if CRET therapy is effective. The investigators will also administer a standard rehabilitation program to both the control and experimental groups.
Participants will:
Come for treatment and evaluations 3 times a week until participants meet the criteria for returning to sports.
Detailed description
Hamstring injuries are the most prevalent pathology in professional football, primarily due to the demands of high-speed running. Beyond threatening athlete health, these injuries account for 12-17% of all time-loss injuries, directly impacting a team's seasonal performance. Research has shown that teams with fewer pre-season hamstring injuries achieve greater success, while the annual financial burden on clubs reaches hundreds of millions of pounds. Recent analyses of 21 years of data from the Union of European Football Associations (UEFA) Elite Club Injury Study reveal that, despite advancements in preventive strategies and training science, hamstring injury rates have not decreased but rather increased by 30% in recent years (5). Given this substantial financial cost, it is evident that current prevention and rehabilitation programs are insufficient, highlighting the need to integrate new therapeutic modalities that optimize tissue healing into clinical practice.
Capacitive and Resistive Electric Transfer (CRET) is a non-invasive electro-physical modality that generates deep endogenous hyperthermia using radiofrequency currents, typically at a stable frequency of 448 kilohertz (kHz). Recent systematic reviews highlight that this method accelerates tissue regeneration not only through its thermal effect but also via biostimulation, which enhances ion mobility by balancing cell membrane potential. By increasing the permeability of ion channels in the cell membrane, it optimizes sodium-potassium (Na/K) pump activity, thereby helping injured and depolarized cells restore their membrane potential. CRET operates through two distinct modes (capacitive and resistive) that focus energy on specific layers based on tissue resistance, allowing it to selectively increase arterial blood perfusion even in deep muscle groups. While these studies recommend CRET for muscle regeneration, there are no randomized controlled trials investigating its efficacy specifically in hamstring injury rehabilitation. Therefore, this study aims to evaluate the effects of CRET-frequently used in clinics and sports clubs-on professional football players with hamstring injuries. The investigators hypothesized that CRET would have positive effects on tissue healing during the subacute phase.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind (outcomes assessor)
- Number of arms
- 2
- Model description
- Two groups including control and experimental groups
| Arm | Type | Receives |
|---|---|---|
| Capacitive and Resistive Electrical Transfer Therapy (CRET) experimental | Experimental | Device: T-Plus; Wintecare SA, Chiasso, Switzerland, Other: ExerciseIn addition to the standard rehabilitation program, the experimental group will receive Capacitive and Resistive Electrical Transfer Therapy (CRET) (T-Plus; Wintecare SA, Chiasso, Switzerland) at the end of each session. |
| Control | Active comparator | Other: ExerciseParticipants in the control group will undergo a standard, evidence-based, three-stage hamstring rehabilitation program. |
Who may qualify
- Ages
- 18 to 40 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult
Key inclusion criteria (3 listed)
- History of acute onset hamstring pain.
- Grade I or II hamstring strain injury confirmed by Magnetic Resonance Imaging (MRI) within the first 5 days following the injury.
- No history of anterior cruciate ligament (ACL) reconstruction.
Key exclusion criteria (3 listed)
- Presence of neurological symptoms.
- Loss of superficial sensation or skin pathologies that may prevent CRET application.
- Refusal to sign the approval form.
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 |
|---|---|---|
| T-Plus; Wintecare SA, Chiasso, SwitzerlandExperimental Group (Capacitive and Resistive Electrical Transfer Therapy (CRET) Therapy): In addition to the standard rehabilitation program, CRET therapy (T-Plus; Wintecare SA, Chiasso, Switzerland) will be applied at the end of each session to the experimental group. Positioning: The athlete will be placed in a prone position, with the passive electrode placed under the quadriceps muscle and the active electrode applied in the direction of the hamstring muscle fibers using classic massage maneuvers. Dosage and Duration: The treatment will last a total of 20 minutes, consisting of 10 minutes in resistive mode followed by 10 minutes in capacitive mode. Intensity: The application will start at 70% intensity. If the thermal sensation reaches a level that disturbs the athlete, the intensity will be gradually reduced by 10% to achieve the maximum tolerable thermal effect. | Device | Capacitive and Resistive Electrical Transfer Therapy (CRET) experimental |
| ExerciseA standard hamstring rehabilitation program consisting of three phases will be implemented. | Other | Capacitive and Resistive Electrical Transfer Therapy (CRET) experimental, Control |
Primary outcome
Return to Sport Time
Time frame: 5 weeks
The primary outcome measure is the number of days from the time of injury to the time when criteria for full return to sports are met.
3 secondary outcomes
Hamstring Flexibility
Time frame: 5 weeks
Hamstring strength
Time frame: 5 weeks
Muscle Oxygen Saturation
Time frame: 5 weeks
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 10 Aug 2026.
- Individual participant dataSharing planned: No
Related trials for Hamstring Injury
Recruiting
Thermal Therapies in the Treatment of Muscle Injuries
Hamstring Injuries, Hamstring Muscle Repair
Not yet recruiting
Correlation Between Soft Tissue Displacement and Functional Performance in Orthopedic Patients
Hamstring Muscle Strain, Adult Acquired Flatfoot Deformity
Recruiting
Soft-tissue Quadriceps Autograft ACL-reconstruction in the Skeletally-immature vs. Hamstrings
ACL - Anterior Cruciate Ligament Rupture
RecruitingObservational study
Neuromuscular Profiles After Anterior Cruciate Ligament Reconstruction
Anterior Cruciate Ligament Injury
Recruiting
Effects Of Criteria Versus Time-Based Rehabilitation On Return To Play In Football Players
Hamstring Muscle Strain
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. This study is not recruiting at the moment.
Irem DUZGUN principal investigator
Hacettepe 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 T-Plus; Wintecare SA, Chiasso, Switzerland and Exercise in people with Hamstring Injury, run by Hacettepe University at 1 site in Turkey (Türkiye).
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 3 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: finished, as of the sponsor's last update on 10 Aug 2026. 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 Turkey (Türkiye). 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?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Return to Sport Time (time frame: 5 weeks). 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 10 Aug 2026.