Patellar TendinopathyPTGRAZ_26/27NCT07682051
Effects of Resistance Training on Patellar Tendon Properties in People With Patellar Tendinoapthy
A study testing Eccentric Training and Heavy-Slow Resistance Training in people with Patellar Tendinopathy, run by University of Graz at 1 site in Austria.
Trial summary
This study aims to investigate the effects of two different resistance training interventions on the structural, morphological, mechanical, and functional properties of the thigh muscles (in particular the quadriceps femoris) and the patellar tendon, in participants with current patellar tendinopathy. Read more about this study
- Who is it for?
- Ages 18 to 50 years
- Conditions the study is for
- Patellar Tendinopathy
- What is being tested?
- Eccentric Training and Heavy-Slow Resistance Training
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 30 participants
- Where
- 1 siteAustria
- Study dates
- 21 Jul 2026to 30 Nov 2027
- 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 50 years
- All sexes
- No healthy volunteers
- Adult
Who may be able to join
- Between 18 and 50 years of age
- Pain at the inferior pole of the patella, longer than 3 months
- Active lifestyle (sport/exercise minimum 3 times per week)
- No previous injuries or surgeries on the affected leg
Who cannot join
- Corticoid injections in the last 6 months
- Current intake of pain or non-steroidal anti-inflammatory drugs
- Additional tendinopathy treatments in the last 6 months (i.e., physical therapy, shock-wave therapy, drug interventions, etc.)
- Neuromuscular or cardiovascular associated diseases or conditions
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
About this study
Official title: Chronic Effects of Eccentric Training and Heavy-Slow Resistance Training on the Structural, Morphological, Mechanical, and Functional Properties of Muscle and Tendon in Participants With Patellar Tendinopathy
This study aims to investigate the effects of two different resistance training interventions on the structural, morphological, mechanical, and functional properties of the thigh muscles (in particular the quadriceps femoris) and the patellar tendon, in participants with current patellar tendinopathy.
Read the detailed description
Patellar tendinopathy is a common musculoskeletal injury among physically active people and athletes, particularly those who play sports that involve high jumps, such as volleyball and basketball. This condition is associated with alterations in the intrinsic properties of the muscle (e.g., cross-sectional area, muscle length) and the patellar tendon (e.g., stiffness, thickness), along with impairments in sports performance (e.g., altered jump height) and tendon pain.
The current gold-standard treatment for tendinopathies is composed mainly of eccentric training, which overall shows a good percentage of remission of the symptoms, but on the other hand, a high percentage of recurrence of said symptoms.
The objectives are to find out if a specific and controlled eccentric training and heavy-slow resistance training, which literature has shown to be a friendly and closer to daily-life movement alternative for management of patellar tendinopathy. Through the assessment of several muscle, tendon, and performance parameters, our study aims to investigate if individually targeted training variables on both training interventions show a better improvement in the intrinsic properties of the anatomical structures, as well as functional and performance parameters like pain level, strength, jump height, etc.
- Conditions
- Patellar Tendinopathy
- Being tested
- Eccentric Training, Heavy-Slow Resistance Training
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Eccentric TrainingOther
Also called ECC
The intervention consists of 12 weeks of resistance training, with a frequency of three times per week. Participants in this group will perform two exercises on a leg press and knee extension machine at their own training facility. This intervention has a repetition time of four seconds, with only the eccentric phase of the movement being performed. They will rest between two and three minutes between sets and will perform the exercises as long as their pain level is less than or equal to four on a pain scale from 0-10.
The training parameters are the following, applying to both leg press and knee extension exercises:
Week 1: 3 sets of 15 repetitions at 60% of their 1-repetition maximum (1RM) Week 2 and 3: 3 sets of 12 repetitions at 70% of their 1RM Week 4 and 5: 3 sets of 10 repetitions at 75% of their 1RM Week 6 to 12: 4 sets of 8 repetitions at 80% of their 1RM.
Heavy-Slow Resistance TrainingOther
Also called HSRT
The intervention consists of 12 weeks of resistance training, with a frequency of three times per week. Participants in this group will perform two exercises on a leg press and knee extension machine at their own training facility. This intervention has a repetition time of four seconds, of which two seconds will be spent on the concentric phase and two seconds on the eccentric phase of the movement being performed. They will rest between two and three minutes between sets and will perform the exercises as long as their pain level is less than or equal to four on a pain scale from 0-10.
The training parameters are the following, applying to both leg press and knee extension exercises:
Week 1: 3 sets of 15 repetitions at 60% of their 1-repetition maximum (1RM) Week 2 and 3: 3 sets of 12 repetitions at 70% of their 1RM Week 4 and 5: 3 sets of 10 repetitions at 75% of their 1RM Week 6 to 12: 4 sets of 8 repetitions at 80% of their 1RM.
| Study group | Role | What they receive |
|---|---|---|
| Eccentric Training | Experimental | Participants between 18 and 50 years of age with patellar tendinopathy who will receive the eccentric intervention only. Receives: Other: Eccentric Training |
| Heavy-Slow Resistance Training | Experimental | Participants between 18 and 50 years of age with patellar tendinopathy who will receive the heavy-slow resistance training intervention only. Receives: Other: Heavy-Slow Resistance Training |
What is being measured
The primary outcome is the main question the study is designed to answer.
Tendon Thickness
Anteroposterior thickness of the patellar tendon (in milimiters) measures by B-Mode Ultrasound (Aixplorer V12.3 Supersonic Imaging, France) with a SuperLinear 15-4 MHz probe. Three images at the same position will be taken for further analysis with the software ImageJ.
Measured: From enrollment to the end of training at 12 weeks
Tendon sitffness
Stiffness of the patellar tendon (in kilopascal) will be measured with Shear-Wave Elastrography (Aixplorer V12.3, Supersonic Imaging, France). The measurement site is 0.5cm from the patellar apex, and five videos of 15 seconds will be recorded for further analysis with Matlab.
Measured: From enrollment to the end of training at 12 weeks
Tendon CSA
Cross-sectional area of the patellar tendon (in centimiters) on its proximal, middle and distal part, will be measured with B-Mode Ultrasound (Aixplorer V12.3, Supersonic Imaging, France). Three images per site, accounting for a total of 9 images, will be taken for further analysis with the software ImageJ.
Measured: From enrollment to the end of training at 12 weeks
Fascicle length
Length of the fascicles of the vastus lateralis muscle (in centimiters) will be measures with Extended Field of View (Panoramic) B-Mode Ultrasound (Aixplorer V12.3, Supersonic Imaging, France). Five images will be taken for further analysis with the software ImageJ.
Measured: From enrollment to the end of training at 12 weeks
Muscle Strength
Maximum voluntary isometric torque of the knee extensors (in newton per meters) will be measured with the Isomed2000, Germany device. Three trials will be performed, with three minutes of rest in between, and the trial with the maximum peak torque will be taken for analysis.
Measured: From enrollment to the end of training at 12 weeks
1 repetition maximum
Maximum strength of the leg press and knee extension exercises (in kilograms) will be measured with the leg press and knee extension devices (compass540, Physiomed, Germany). Participants will perform repetitions with increasing weights, until they can perform a maximum of eight repetitions with a specific weight. This weight will be then used to estimate their maximum 1RM, to further calculate the training loads.
Measured: From enrollment to the end of training at 12 weeks
Overall Pain
Pain assessed at rest and during a single-leg-decline squat (SLDS) will be assessed with the numerical rating scale of 11 points called Visual Analogue Scale (VAS). Higher values mean higher pain levels.
Measured: From enrollment to the end of training at 12 weeks
Functionality
Functionality assessed with the VISA-P Questionnaire. This questionnaire includes 10 questions with a score from 0 to 10, for a maximum questionnaire score of 100 points. Higher scores mean better functionality.
Measured: From enrollment to the end of training at 12 weeks
Secondary outcomes (5)
Tendon Neovascularization
Presence of blood vessels in the patellar tendon will be analysed with Color Doppler Ultrasound (MyLab60, Esaote S.p.A., Italy). The measurement site is 0.5cm from the patellar apex. Five videos of 15 seconds each will be taken for further analysis with Matlab.
Measured: From enrollment to the end of training at 12 weeks
Young's Modulus
Tendon Young's Modulus (in kilopascal) will be assessed with Shear-Wave Elastography (Aixplorer V12.3, Supersonic Imaging, France).
Measured: From enrollment to the end of training at 12 weeks
Muscle Thickness
Thickness of the vastus lateralis muscle (in centimiters) will be obtained with Extended Fielv of View Panoramic Ultrasound (Aixplorer V12.3, Supersonic Imaging, France). Five images will be taken, and muscle thickness will be measures on three places on the thickest part of the muscle, and averaged for further analysis with ImageJ.
Measured: From enrollment to the end of training at 12 weeks
Muscle Stiffness
Stiffness of the vastus lateralis tendon (in kilopascal) will be measured with Shear-Wave Elastrography (Aixplorer V12.3, Supersonic Imaging, France). The measurement site is 60% of the length of the muscle, from the greater trochanter to the lateral femur condyle. Five videos of 15 seconds will be recorded for further analysis with Matlab.
Measured: From enrollment to the end of training at 12 weeks
Jump Height
Height of the Countermovement Jump measured with Kinvent Force Plates will be assessed. The participants will perform three jumps with two minutes rest in between them.
Measured: From enrollment to the end of training at 12 weeks
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted2 Jul 2026
- Study start21 Jul 2026
- Primary completion30 Jun 2027 (estimated)
- Study completion30 Nov 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Patellar TendinopathyStudies 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
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- The study is designed as a randomized controlled trial (RCT). This means the participants will be randomly assigned to one of two intervention groups: * Eccentric group: the intervention group will perform an eccentric resistance training protocol for 12 weeks. This means the focus is on the deceleration or "return" part of the movement. * Heavy-slow resistance training: this group will perform both the concentric and the eccentric parts of the exercises for 12 weeks. In simple words, a closer-to-normal strength training protocol.
- Masking
- None (open label)
- Enrolment
- 30 participants (estimated)
Sponsor and investigators
- Lead sponsor
- University of Graz
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Josefina Manieu, University of Graz
- Investigators
- Josefina Manieu Seguel, M.Sc., Principal investigator, University of Graz
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07682051
- Sponsor's protocol ID
- GZ. 39/255/63
- Acronym
- PTGRAZ_26/27
- Status last verified
- Sep 2026
- First submitted
- 23 Jun 2026
- Last updated
- 9 Sep 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes: Metrics obtained from the outcome variables. No personal information will be shared (e.g., name, gender, anthropometrics)
Study at a glance
From the registry record, last updated by the sponsor on 9 Sep 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Chronic Effects of Eccentric Training and Heavy-Slow Resistance Training on the Structural, Morphological, Mechanical, and Functional Properties of Muscle and Tendon in Participants With Patellar Tendinopathy
- ClinicalTrials.gov ID
- NCT07682051
- Acronym / sponsor ID
- PTGRAZ_26/27 / GZ. 39/255/63
- Conditions
- Patellar Tendinopathy
- Study type
- Interventional
- Recruitment status
- Enrolling by invitation
- Enrolment
- 30 participants (estimated)
- Lead sponsor
- University of GrazUniversity, hospital or other
- Study start
- 21 Jul 2026 (actual)
- Primary completion
- 30 Jun 2027 (estimated)
- Study completion
- 30 Nov 2027 (estimated)
- First posted
- 2 Jul 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.
This study aims to investigate the effects of two different resistance training interventions on the structural, morphological, mechanical, and functional properties of the thigh muscles (in particular the quadriceps femoris) and the patellar tendon, in participants with current patellar tendinopathy.
Detailed description
Patellar tendinopathy is a common musculoskeletal injury among physically active people and athletes, particularly those who play sports that involve high jumps, such as volleyball and basketball. This condition is associated with alterations in the intrinsic properties of the muscle (e.g., cross-sectional area, muscle length) and the patellar tendon (e.g., stiffness, thickness), along with impairments in sports performance (e.g., altered jump height) and tendon pain.
The current gold-standard treatment for tendinopathies is composed mainly of eccentric training, which overall shows a good percentage of remission of the symptoms, but on the other hand, a high percentage of recurrence of said symptoms.
The objectives are to find out if a specific and controlled eccentric training and heavy-slow resistance training, which literature has shown to be a friendly and closer to daily-life movement alternative for management of patellar tendinopathy. Through the assessment of several muscle, tendon, and performance parameters, our study aims to investigate if individually targeted training variables on both training interventions show a better improvement in the intrinsic properties of the anatomical structures, as well as functional and performance parameters like pain level, strength, jump height, etc.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
- Model description
- The study is designed as a randomized controlled trial (RCT). This means the participants will be randomly assigned to one of two intervention groups: * Eccentric group: the intervention group will perform an eccentric resistance training protocol for 12 weeks. This means the focus is on the deceleration or "return" part of the movement. * Heavy-slow resistance training: this group will perform both the concentric and the eccentric parts of the exercises for 12 weeks. In simple words, a closer-to-normal strength training protocol.
| Arm | Type | Receives |
|---|---|---|
| Eccentric Training | Experimental | Other: Eccentric TrainingParticipants between 18 and 50 years of age with patellar tendinopathy who will receive the eccentric intervention only. |
| Heavy-Slow Resistance Training | Experimental | Other: Heavy-Slow Resistance TrainingParticipants between 18 and 50 years of age with patellar tendinopathy who will receive the heavy-slow resistance training intervention only. |
Who may qualify
- Ages
- 18 to 50 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult
Key inclusion criteria (4 listed)
- Between 18 and 50 years of age
- Pain at the inferior pole of the patella, longer than 3 months
- Active lifestyle (sport/exercise minimum 3 times per week)
- No previous injuries or surgeries on the affected leg
Key exclusion criteria (4 listed)
- Corticoid injections in the last 6 months
- Current intake of pain or non-steroidal anti-inflammatory drugs
- Additional tendinopathy treatments in the last 6 months (i.e., physical therapy, shock-wave therapy, drug interventions, etc.)
- Neuromuscular or cardiovascular associated diseases or conditions
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 |
|---|---|---|
| Eccentric TrainingAlso: ECCThe intervention consists of 12 weeks of resistance training, with a frequency of three times per week. Participants in this group will perform two exercises on a leg press and knee extension machine at their own training facility. This intervention has a repetition time of four seconds, with only the eccentric phase of the movement being performed. They will rest between two and three minutes between sets and will perform the exercises as long as their pain level is less than or equal to four on a pain scale from 0-10. The training parameters are the following, applying to both leg press and knee extension exercises: Week 1: 3 sets of 15 repetitions at 60% of their 1-repetition maximum (1RM) Week 2 and 3: 3 sets of 12 repetitions at 70% of their 1RM Week 4 and 5: 3 sets of 10 repetitions at 75% of their 1RM Week 6 to 12: 4 sets of 8 repetitions at 80% of their 1RM. | Other | Eccentric Training |
| Heavy-Slow Resistance TrainingAlso: HSRTThe intervention consists of 12 weeks of resistance training, with a frequency of three times per week. Participants in this group will perform two exercises on a leg press and knee extension machine at their own training facility. This intervention has a repetition time of four seconds, of which two seconds will be spent on the concentric phase and two seconds on the eccentric phase of the movement being performed. They will rest between two and three minutes between sets and will perform the exercises as long as their pain level is less than or equal to four on a pain scale from 0-10. The training parameters are the following, applying to both leg press and knee extension exercises: Week 1: 3 sets of 15 repetitions at 60% of their 1-repetition maximum (1RM) Week 2 and 3: 3 sets of 12 repetitions at 70% of their 1RM Week 4 and 5: 3 sets of 10 repetitions at 75% of their 1RM Week 6 to 12: 4 sets of 8 repetitions at 80% of their 1RM. | Other | Heavy-Slow Resistance Training |
Primary outcome
Tendon Thickness
Time frame: From enrollment to the end of training at 12 weeks
Anteroposterior thickness of the patellar tendon (in milimiters) measures by B-Mode Ultrasound (Aixplorer V12.3 Supersonic Imaging, France) with a SuperLinear 15-4 MHz probe. Three images at the same position will be taken for further analysis with the software ImageJ.
Tendon sitffness
Time frame: From enrollment to the end of training at 12 weeks
Stiffness of the patellar tendon (in kilopascal) will be measured with Shear-Wave Elastrography (Aixplorer V12.3, Supersonic Imaging, France). The measurement site is 0.5cm from the patellar apex, and five videos of 15 seconds will be recorded for further analysis with Matlab.
Tendon CSA
Time frame: From enrollment to the end of training at 12 weeks
Cross-sectional area of the patellar tendon (in centimiters) on its proximal, middle and distal part, will be measured with B-Mode Ultrasound (Aixplorer V12.3, Supersonic Imaging, France). Three images per site, accounting for a total of 9 images, will be taken for further analysis with the software ImageJ.
Fascicle length
Time frame: From enrollment to the end of training at 12 weeks
Length of the fascicles of the vastus lateralis muscle (in centimiters) will be measures with Extended Field of View (Panoramic) B-Mode Ultrasound (Aixplorer V12.3, Supersonic Imaging, France). Five images will be taken for further analysis with the software ImageJ.
Muscle Strength
Time frame: From enrollment to the end of training at 12 weeks
Maximum voluntary isometric torque of the knee extensors (in newton per meters) will be measured with the Isomed2000, Germany device. Three trials will be performed, with three minutes of rest in between, and the trial with the maximum peak torque will be taken for analysis.
1 repetition maximum
Time frame: From enrollment to the end of training at 12 weeks
Maximum strength of the leg press and knee extension exercises (in kilograms) will be measured with the leg press and knee extension devices (compass540, Physiomed, Germany). Participants will perform repetitions with increasing weights, until they can perform a maximum of eight repetitions with a specific weight. This weight will be then used to estimate their maximum 1RM, to further calculate the training loads.
Overall Pain
Time frame: From enrollment to the end of training at 12 weeks
Pain assessed at rest and during a single-leg-decline squat (SLDS) will be assessed with the numerical rating scale of 11 points called Visual Analogue Scale (VAS). Higher values mean higher pain levels.
Functionality
Time frame: From enrollment to the end of training at 12 weeks
Functionality assessed with the VISA-P Questionnaire. This questionnaire includes 10 questions with a score from 0 to 10, for a maximum questionnaire score of 100 points. Higher scores mean better functionality.
5 secondary outcomes
Tendon Neovascularization
Time frame: From enrollment to the end of training at 12 weeks
Young's Modulus
Time frame: From enrollment to the end of training at 12 weeks
Muscle Thickness
Time frame: From enrollment to the end of training at 12 weeks
Muscle Stiffness
Time frame: From enrollment to the end of training at 12 weeks
Jump Height
Time frame: From enrollment to the end of training at 12 weeks
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 9 Sep 2026.
- Individual participant dataSharing planned: Yes. Metrics obtained from the outcome variables. No personal information will be shared (e.g., name, gender, anthropometrics)
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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.
Josefina Manieu Seguel, M.Sc. principal investigator
University of Graz
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Eccentric Training and Heavy-Slow Resistance Training in people with Patellar Tendinopathy, run by University of Graz at 1 site in Austria.
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 4 inclusion and 4 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: enrolling by invitation, as of the sponsor's last update on 9 Sep 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 Austria. 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?
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?
Tendon Thickness (time frame: From enrollment to the end of training at 12 weeks). The study lists 8 primary outcomes in all. 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 9 Sep 2026.