Acute Effects of Static Stretching Intensity and Duration on Muscle Viscoelastic Properties and Proprioception

Study Overview
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Brief Summary
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The purpose of this study is to compare the acute effects of different duration and intensity of static stretching exercises on the viscoelastic properties of the hamstring muscle and the knee proprioception.

Detailed Description
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Traditionally stretching exercises have been used by health professionals as a means of preventing injuries by increasing performance and increasing joint flexibility. Kubo et al. suggest that the potential mechanism of decreased risk of injury with increased flexibility is a change in the viscoelastic properties of the muscle-tendon unit. Muscle fibers and tendons contain proprioceptors. These receptors provide information about joint angle, muscle length and muscle tension. There are two stretch-related proprioceptors that transmit information to the central nervous system about muscle tension. These receptors are muscle spindles (respond to changes in the length) and golgi tendon organs (respond to changes in the tension). For this reason, interactions between muscle tension, muscle-tendon unit, viscoelasticity and proprioceptive tissue (muscle spindles and golgi tendon organ); it becomes important when you think about how stretching exercises affect proprioception, flexibility and increase or decrease of joint range of motion. In the literature, four stretching parameters have been defined as important to influence the potential for increasing or decreasing the flexibility of a joint: intensity, duration, frequency and stretching position. The focus of this study we plan on is the intensity and duration of stretching. Exercise warming exercises before sportive activity and cooling exercises afterwards are widely suggested and applied. Determining the relationship between stretch severity and duration and viscoelastic properties and proprioception will contribute to the effective creation of training programs.

Official Title
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Acute Effects of Static Stretching Intensity and Duration on Muscle Viscoelastic Properties and Proprioception

Conditions
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Static Stretching

Intervention / Treatment
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* Other: Static Stretching Exercise


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Being in the 18-45 age range. Volunteer to participate in the study. Exclusion Criteria: Having had previous lower extremity operations. Having an orthopedic, neurological and rheumatologic disease of the lower extremities. Having open wound in the application area. Having had soft tissue injury in the last 6 weeks in the application area.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 45 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: Other
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: 30 seconds and %50 intensity stretching<br>The participants in this group performed an 30 seconds, %50 intensity static stretching exercise. 3 repetitive static stretching exercises did to hamstring muscles on the dominant side. | Other: Static Stretching Exercise<br>* Each intervention group received a different duration and intensity of static stretching exercise protocol.<br>|
| Experimental: 30 seconds and %75 intensity stretching<br>The participants in this group performed an 30 seconds, %75 intensity static stretching exercise. 3 repetitive static stretching exercises did to hamstring muscles on the dominant side. | Other: Static Stretching Exercise<br>* Each intervention group received a different duration and intensity of static stretching exercise protocol.<br>|
| Experimental: 30 seconds and %100 intensity stretching<br>The participants in this group performed an 30 seconds, %100 intensity static stretching exercise. 3 repetitive static stretching exercises did to hamstring muscles on the dominant side. | Other: Static Stretching Exercise<br>* Each intervention group received a different duration and intensity of static stretching exercise protocol.<br>|
| Experimental: 60 seconds and %50 intensity stretching<br>The participants in this group performed an 60 seconds, %50 intensity static stretching exercise. 3 repetitive static stretching exercises did to hamstring muscles on the dominant side. | Other: Static Stretching Exercise<br>* Each intervention group received a different duration and intensity of static stretching exercise protocol.<br>|
| Experimental: 60 seconds and %75 intensity stretching<br>The participants in this group performed an 60 seconds, %75 intensity static stretching exercise. 3 repetitive static stretching exercises did to hamstring muscles on the dominant side. | Other: Static Stretching Exercise<br>* Each intervention group received a different duration and intensity of static stretching exercise protocol.<br>|
| Experimental: 60 seconds and %100 intensity stretching<br>The participants in this group performed an 60 seconds, %100 intensity static stretching exercise. 3 repetitive static stretching exercises did to hamstring muscles on the dominant side. | Other: Static Stretching Exercise<br>* Each intervention group received a different duration and intensity of static stretching exercise protocol.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change from baseline muscle viscoelastic properties at immediately after exercise | Muscle viscoelastic properties was assessed with Myoton® PRO device. It is an evidence-based device that evaluates the bio-mechanical properties of soft biological tissues in a non-invasive, objective, reliable, inexpensive, quick and easy manner. Myoton® PRO is used in studies to evaluate superficial skeletal muscles, connective tissues such as tendons and ligaments, and other soft tissues. It is a highly reliable method for assessing the tone, stiffness, elasticity of muscles. | 10 minutes | 
| Change from baseline proprioception at immediately after exercise | Proprioception was assessed with MarVAJED (Marmara Visual Auditory Joint Education Device). MarVAJED is a system for evaluating joint range of motion, analyzing joint position sense, offering biofeedback support to increase joint control, as well as directing it to controlled exercises. Analyzes joint movement with the help of small sensors. Transfers the obtained data to mobile phone, tablet or personal computer. | 10 minutes | 
| Change from baseline static stretching exercise intensity at the beginning of each exercise | A visual analog scale of 100 mm was used to assess the intensity of stretching exercise perceived by the participant at the beginning of each repetition. The visual analog scale is used to visually measure the intensity of the detected mechanical stimulus. 0 means no stretch and 100 means maximum tolerable stretch without pain. Perceived violence from left to right increases. | 10 minutes | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Static Stretching, Stiffness, Proprioception, Healthy adults