Effects of Long-term Foam Rolling Compared to Static Stretching on Hamstring Muscle Flexibility

Study Overview
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Brief Summary
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The purpose of this study to to compare the long-term effects of foam rolling in comparison to static stretching and a control group on hamstring flexibility. The investigators hypothesize that participants in the foam rolling and static stretching group will demonstrate increased flexibility to the control group, but will a difference will not be observed between the foam rolling and static stretching groups.

Conditions
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Muscle Hypertonia

Intervention / Treatment
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* Other: Foam Rolling
* Other: Static Stretching


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Active 90/90 hamstring length goniometric measurement of greater than 10 degrees at baseline Active straight leg raise of less than 90 degrees Exclusion Criteria: History of lower extremity injury including but not limited to sprain, strain, fracture, or any surgical intervention that lead to a decrease in activity greater than two weeks within the last six months Current involvement in a lower extremity flexibility program outside of their regular activity

Ages Eligible for Study
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Minimum Age: 19 Years
Maximum Age: 40 Years

Sexes Eligible for Study
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All

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: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Foam rolling<br>Participants in the foam rolling group will perform unilateral rolling of the hamstring musculature from ischial tuberosity to posterior knee in supine for 2 repetitions of 1 minute with 15 second rest between repetitions at a consistent cadence of 1 second superiorly and 1 second inferiorly. Subjects will be asked to adjust pressure as needed to maintain a consistent moderate pressure on the treatment area. Participants will use new and individually issued high density foam rollers that are 6 diameter x 36 length. | Other: Foam Rolling<br>* Participants will perform unilateral hamstring rolling for 2 repetitions of 1 minute with 15 second rest breaks on each leg with a 6x 36 foam roller.<br>|
| Experimental: Static stretching<br>Participants in the static stretching group will perform sustained static hamstring stretching for 2 repetitions of 1 minute bouts for the same leg before switching sides using moderate pressure in supine against the wall. Subjects will rest for 15 seconds between repetitions and adjust distance from the wall to perceive moderate intensity. | Other: Static Stretching<br>* Participants will perform supine static hamstring stretch on a wall for 2 repetitions of 1 minute with 15 second rest breaks on each leg. When the position no longer causes a moderate stretching sensation to the hamstring, subjects will move their bodies closer to the wall to intensify the stretch.<br>|
| No Intervention: Control<br>The control group will perform their regular baseline activities without the addition of a specific lower extremity flexibility program. If the subjects are currently performing stretching of any mode at baseline, they will be allowed to continue with that activity. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in 90/90 hamstring length | Participant is supine, hip flexed to 90 degrees, knee extension range of motion measured actively from 90 degree starting position with a standard goniometer | Baseline, 3 weeks, 6 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Active straight leg raise - Range of motion | Participant is supine, with contralateral leg straight the participant will actively raise the leg until end of range with hip flexion being measured by goniometer | Baseline, 3 weeks, 6 weeks | 
| Change in Active straight leg raise - Functional Movement Screen | Participant is supine, with contralateral leg straight the participant will actively raise the leg until end of range. This end range will be compared to a standardized position using a dowel and will be scored according to the functional movement screen. | Baseline, 3 weeks, 6 weeks | 
| Change in Sit-and-reach | Using a standardized sit-and-reach box, participants will sit with legs together, knees extended, and hands overlapped and extended in front of the body. The subject will forward flex until end range of motion measured in centimeters. | Baseline, 3 weeks, 6 weeks |