Acute Effects of Dynamic Stretching, Plyometrics, and Loading on Achilles Tendon Properties and Performance Outcomes

Study Overview
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Brief Summary
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The study will be looking at acute changes in Achilles tendon properties and changes in a vertical single leg hop following an exercise intervention. The three exercise interventions will be randomized and take place on separate days 1 week apart. The three exercise interventions are AAROM, slow load, and plyometrics.

Detailed Description
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The purpose of the study is to determine if there are acute changes in Achilles tendon properties and changes in performance based on what tendon exercise intervention is being used. About 70 people will take part in this research.

Official Title
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Acute Effects of Dynamic Stretching, Plyometrics, and Loading on Achilles Tendon Properties and Performance Outcomes

Conditions
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Tendon Injuries

Intervention / Treatment
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* Other: AAROM
* Other: Slow Load
* Other: Plyometric


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: College student Exclusion Criteria: Unable to complete interventions

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Group 1<br>Randomized AAROM, Slow Load, or Plyometric intervention | Other: AAROM<br>* AAROM with knee to wall exercise, 3x30 reps<br>Other: Slow Load<br>* Single leg heel raise, 3x10 reps<br>Other: Plyometric<br>* Double leg 5 inch wall hops, 3x10 sec<br>|
| Experimental: Group 2<br>Randomized AAROM, Slow Load, or Plyometric intervention | Other: AAROM<br>* AAROM with knee to wall exercise, 3x30 reps<br>Other: Slow Load<br>* Single leg heel raise, 3x10 reps<br>Other: Plyometric<br>* Double leg 5 inch wall hops, 3x10 sec<br>|
| Experimental: Group 3<br>Randomized AAROM, Slow Load, or Plyometric intervention | Other: AAROM<br>* AAROM with knee to wall exercise, 3x30 reps<br>Other: Slow Load<br>* Single leg heel raise, 3x10 reps<br>Other: Plyometric<br>* Double leg 5 inch wall hops, 3x10 sec<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Achilles Tendon Stiffness | A myotonometer will measure the stiffness in N/m. | immediately | 
| Achilles Tendon Natural Oscillation | A myotonometer will measure the natural oscillation frequency in Hz. | immediately | 
| Achilles Tendon Logarithmic Decrement | A myotonometer will measure logarithmic decrement, which is a measure of elasticity. | immediately | 
| Achilles Tendon Mechanical Stress Relaxation Time | A myotonometer will measure mechanical stress relaxation time in ms. | immediately | 
| Achilles Tendon Creep | A myotonometer will measure creep in De. | immediately | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Single-leg drop jump vertical | Single-leg vertical drop jump from 4-inch box with knee locked in extension will be measured in cm. A higher jump is considered better. | immediately | 
| Reactive Strength Index | Reactive Strength Index will be measured as an AU, the higher the better. | immediately | 
| Flight Time | Flight time will be measured in ms, the higher the better. | immediately | 
| Contact Time | Contact time will be measured in ms, the lower the better. | immediately | 
| Limb Stiffness | Limb stiffness will be measured in kN/m, generally the higher the better. | immediately |