Effect of Collagen Supplementation on Tendinopathy

Study Overview
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Brief Summary
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Tendon injuries represent a significant problem in elite athletes. Therefore, prevention and effective treatment of tendon overload injury/tendinopathy is important. Among different treatment options, heavy-slow loading based rehabilitation is considered among the most efficient treatments in athletes. In this study, we will investigate if supplementation with hydrolyzed collagen in combination with a heavy-slow loading based 12 weeks rehabilitation regime can improve treatment of tendon overload injury/tendinopathy. The investigators will examine elite athletes with overload injury/tendinopathy with regards to symptoms (pain, function), tendon morphology (ultrasonography), and vascularization (Doppler US). The investigators hypothesize that collagen supplementation can have an improving effect on tendon pain and function. Thus, the investigation will show if a rehabilitation regime of collagen supplementation combined with heavy-slow mechanical loading can improve tendon healing compared to mechanical loading alone.

Detailed Description
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Randomized placebo-controlled intervention study with follow-up after one month

Official Title
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Effect of Collagen Supplementation on Tendinopathy in Elite Athletes

Conditions
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Tendinopathy

Intervention / Treatment
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* Dietary Supplement: Hydrolyzed collagen
* Other: Heavy slow resistance training
* Dietary Supplement: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Elite athletes 18-40 years old Exercise related tendon pain on one or both legs Soreness during physical examination of tendon upon palpation Uni- or bilateral tendinopathy symptoms > 3 months Exclusion Criteria: Previous tendon surgery Diabetes Arthritis Corticosteroid injection for tendinopathy within the last 3 months Any form of tendon injection within the last 3 months Smoking

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 40 Years

Sexes Eligible for Study
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Male

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Collagen + heavy slow resistance group<br>Daily collagen supplementation + heavy slow resistance training three times weekly for 12 weeks. | Dietary Supplement: Hydrolyzed collagen<br>* Hydrolyzed collagen supplementation twice daily<br>Other: Heavy slow resistance training<br>* Heavy slow resistance training 3 times weekly<br>|
| Experimental: Placebo + heavy slow resistance group<br>Daily placebo supplementation + heavy slow resistance training three times weekly for 12 weeks. | Other: Heavy slow resistance training<br>* Heavy slow resistance training 3 times weekly<br>Dietary Supplement: Placebo<br>* Placebo supplementation twice daily<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Maximal tendon pain during the past week at preferred sporting activity | Change from baseline - 12 weeks using the Numerical Rating Scale (NRS; 0= no pain, 10 = worst imaginable pain) | Baseline-12 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Maximal tendon pain during the past week at preferred sporting activity | Change from baseline - 6 weeks + 1 month follow-up using the Numerical Rating Scale (NRS; 0= no pain, 10 = worst imaginable pain) | Baseline, 6 weeks + 6 month follow-up | 
| Self-reported activity level of sporting activities (hours/week) | Participants will self-report how many hours a week they are performing sporting activities: We will monitor to see if they decrease, maintain or increase hours per week of sporting activity | Baseline, 6 and 12 weeks + 6 month follow-up | 
| Single-leg decline squat (SLDS) test | A reliable patellar tendon pain provocation test, will be used to assess pain during function using the Numerical Rating Scale (NRS; 0= no pain, 10 = worst imaginable pain) | Baseline - 12 weeks | 
| Jump test | A reliable Achilles/Plantaris tendon pain provocation test, will be used to assess pain during function using the Numerical Rating Scale (NRS; 0= no pain, 10 = worst imaginable pain) | Baseline - 12 weeks | 
| Treatment satisfaction | Participants will be asked after the intervention period whether they were satisfied or not with the treatment (dichotom : Yes vs. No) | 12 weeks | 
| Collagen supplement | Participants will be asked on a weekly basis if taken their collagen supplement : Questionnaire (dichotom : Yes vs. No) | Baseline - 12 weeks + 6 month follow-up | 
| Adverse events (e.g. allergies, gastro-intestinal side effects) related to supplement ingestion | Participants will self-report adverse events during intervention period and at 6 month follow-up | Baseline - 12 weeks + 6 month follow-up | 
| Return-to-sport activities | Participants will self-report Return-to-sport activities during intervention period and at 6 month follow-up (dichotom : Yes vs. No) | Baseline - 12 weeks + 6 month follow-up | 
| Change from baseline Victorian Institute of Sports Assessment - Patella/Achilles Questionnaire (VISA-P/A) at 12 wks | Patient reported outcome regarding symptoms, function and the ability to participate in sports | Baseline, 6 and 12 weeks + 6 month follow-up | 
| Change from baseline Foot function index - Plantaris questionnaire at 12 wks | Patient reported outcome regarding symptoms, function and the ability to participate in sports | Baseline, 6 and 12 weeks + 6 month follow-up | 
| Tendon Doppler activity using Ultrasonography power Doppler | Using Ultrasonography, we will measure Doppler activity within the affected tendon and use ImageJ for the analysis | Baseline - 12 weeks | 
| Tendon thickness measured using Ultrasonography |  | Baseline - 12 weeks | 
| Pain rating on Numeric Rating Scale (NRS; 0 = no pain; 10 = worst imaginable pain) during training. |  | Baseline, 6 and 12 weeks + 6 month follow-up |