Acute Effect of Static Stretching and Pilates Stretching on the Muscle Strength

Study Overview
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Brief Summary
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Introduction: Studies have shown that static stretching performed immediately before strength exercises impairs performance. However, unlike static stretching, dynamic stretching performed immediately before muscular strength exercises does not seem to result in worse performance, and in some cases may even provide greater strength performance. Still, the literature is controversial and inconclusive to date. Objective: To verify the acute effect of static stretching versus dynamic stretching on the muscle strength of young university students. Methods: The sample will consist of 102 physically active young university students, of both sexes, aged between 18 and 25 years old, subdivided into three groups: Group 1 - static stretching; Group 2 - dynamic stretching; and Group 3 - control. Everyone will undergo assessment of the isokinetic peak torque of the knee extensor and flexor muscles at 60º/s and 180º/s in the dominant lower limb. Next, the experimental groups (Groups 1 and 2) will perform static or dynamic stretching exercises for the quadriceps and hamstring muscles, while the control group will not perform any activity. Finally, everyone will undergo muscle strength assessment again according to the same procedures used initially. Analysis of covariance (ANCOVA) will be used to compare groups, with data from the initial assessment as adjustment covariates.

Official Title
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Acute Effect of Static Stretching and Pilates Stretching on the Concentric Muscle Strength of the Knee Extensors and Flexors

Conditions
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Muscle Strength, Muscle Strength Dynamometer

Intervention / Treatment
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* Other: Static stretching
* Other: Pilates stretching


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: to practice systematic physical exercises at least three times a week over the last six months; healthy young adults, aged between 18 and 25 years; agree to participate in the study by signing the Free and Informed Consent Form. Exclusion Criteria: musculoskeletal injuries in the lower limbs; pregnancy.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 25 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: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Static stretching<br>A equipment (Ladder Barrel), used in Pilates sessions, will help with the movement. To stretch the knee flexor muscles, the participant, standing, will place the dominant lower limb on the equipment and keep the other on the ground, remaining with both knees extended. The trunk will be flexed forward within the maximum range of movement achieved by the participant, until discomfort occurs in the posterior region of the thigh, but not pain. To stretch the knee extensor muscles, the participant, standing, will position the back of the foot of the dominant lower limb on the equipment and keep the other limb with the foot flat on the ground. The glute of the dominant lower limb will meet the heel of the same limb, until there is discomfort, but not pain. In both stretches, the position will be maintained for 30 seconds, followed by an equal rest time. Three series of stretching will be performed for the knee flexor muscles and then another three series for the extensor muscles. | Other: Static stretching<br>* Stretching exercises performed by maintaining the point of muscular discomfort without changing position for a certain period of time.<br>|
| Experimental: Pilates stretching<br>The protocol will be the same as the Static stretching Group, with the exception of maintaining the static position during the exercise. To do this, when stretching the knee flexor muscles, the trunk will perform continuous flexion movements until the point of muscular discomfort, followed by the extension movement, until an upright posture, continuously. On the other hand, when stretching the knee extensor muscles, the gluteal muscle of the dominant lower limb will meet the heel of the same limb, until there is discomfort, followed by the movement away, continuously. | Other: Pilates stretching<br>* Stretching exercises performed dynamically, following the six basic principles of Pilates: concentration, control, center, precision, breathing and fluidity.<br>|
| No Intervention: Control<br> | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Muscle strength | Concentric muscle strength of the knee extensors and flexors | Acute (immediate) effect: pre-intervention and post-intervention (10 minutes after pre-intervention) |