Acute Effects of Foam Rolling on Viscoelastic Tissue Properties and Fascial Sliding

Study Overview
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Brief Summary
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Treatment or training of fascial tissues has moved into the focus of medical research in the last decade. In this context, the use of foam rollers or roller massagers for self-myofascial-release (SMR) techniques has become increasingly popular in health and fitness professionals. The primary objective of these techniques is to mimic manual massage or myofascial-release therapy with a self-usable tool. Recent studies suggest that SMR improves, inter alia, range of motion (ROM) without a decrease in neuromuscular performance (Cheatham et al. 2015). Concurrent effects on the muscle and especially the surrounding connective tissue network have been proposed as underlying mechanisms for these observed changes in ROM after SMR. Several authors assume a positive effect of SMR on sliding properties of different independent fascial layers. Also, changes in passive tissue stiffness is suggested. Passive stiffness is thereby characterized by passive resistance in the tissues' (muscles') functional direction, the passive resistive torque (PRT). In conclusion, for many of the proclaimed effects of SMR, such as improvements of sliding of fascial layers or decreases of passive stiffness, there is a lack of evidence in the literature. Therefore, the aim of the study is to evaluate acute effects of SMR on the viscoelastic properties of the muscles on the anterior thigh and the corresponding fascia. In a cross over design, 16 subjects receive all of the following interventions after a familiarization session: a) 2x60 seconds of SMR at the anterior thigh, b) 2x60 seconds of static stretching at the anterior thigh, c) no intervention in a balanced permutated randomization sequence. Before and directly after each intervention, outcome parameters are collected. Passive Resistive Torque is evaluated using a computerized isokinetic dynamometer. In passive mode, the lower leg is moved from full knee extension (0°) to the point of maximal knee flexion with a velocity of 5°/s. Torque and angle are recorded at 100 Hertz (Hz). Sliding of fascial layers is quantified with a frame-by-frame cross correlation algorithm of high-resolution ultrasound images (Dilley et al. 2001). First stretch sensation is quantified using the passive mode in the isokinetic dynamometer. Maximal ROM is detected using a an ultrasonographic movement analysis system in a prone position.

Official Title
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Acute Effects of Foam Rolling on Viscoelastic Tissue Properties and Fascial Sliding: A Randomized, Controlled Crossover Trial

Conditions
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Fascia, Self-Myofascial-Release, Passive Stiffness, Fascial Sliding, Flexibility

Intervention / Treatment
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* Other: Self-Myofascial-Release
* Other: Stretching


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age between 20-40 years Exclusion Criteria: History of orthopedic injuries in the lower extremity in the last 12 months Any history of psychiatric, cardiovascular, endocrine, neurological, or metabolic disorders Any current medication that might affect pain perception or proprioception Muscle soreness Pregnancy/nursing period Nonspecific musculoskeletal disorders

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 40 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: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Self-Myofascial-Release<br>Two 60 seconds bouts of Self-Myofascial-Release performed at the anterior thigh; anticipated intensity of 7/10 on a 10 point numeric rating scale (0 representing no discomfort and 10 representing maximal discomfort) | Other: Self-Myofascial-Release<br>* Self-Myofascial-Release performed at the anterior thigh<br>|
| Active Comparator: Stretching<br>Two 60 seconds bouts of static stretching performed at the anterior thigh; anticipated intensity of 7/10 on a 10 point numeric rating scale (0 representing no discomfort and 10 representing maximal discomfort) | Other: Stretching<br>* Static Stretching performed at the anterior thigh<br>|
| No Intervention: Control<br>No Intervention | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Passive-Resistive-Torque, Biodex System 3 Professional | In passive mode, the lower leg is moved from full knee extension (0°) to the point of maximal knee flexion with a velocity of 5°/s. Torque and angle are recorded at 100 Hz, and passive stiffness can be calculated from the torque-angle relationship. | 1 minute | 
| Fascial-Sliding, Siemens Acuson X300, Cross correlation | Sliding of fascial layers is quantified with a frame-by-frame cross correlation algorithm of high-resolution ultrasound images. The cross-correlation method calculates the correlation coefficient between the pixel grey levels for selected rectangle-shaped regions of interest (ROIs) in two adjacent images. The pixel shift that gives the maximum correlation coefficient corresponds to the relative movement between two frames. | 1 minute | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Maximal Range of Motion, Zebris CMS20 | A triplet of ultrasonographic markers is placed on the lower leg, a second triplet is placed as a reference on the thigh. Participants are placed on a physio table including a pre-stretch of the hip (210° in total) using a bed wedge (30°). In this position, participants are instructed to perform three consecutive active knee flexion-extension cycles at a self-selected velocity. Subsequently, the investigator performs three passive knee flexion-extension cycles. Movements are recorded in three dimensions at 20 Hz, and maximal active as well as passive ROM can be calculated as the maximal displacement relative to the starting position recorded by the US markers. | 1 minute | 
| First stretch sensation, Biodex System 3 Professional | Position of the first stretch sensation is quantified using the isokinetic dynamometer in the above-described position. In passive mode, the knee is flexed from full extension to flexion at 5°/s. The subject uses a switch to stop the passive movement at the position of first stretch sensation. | 1 minute |