Effects of a 60-min Repeated Trunk Flexion Protocol on Trunk Neuromuscular Properties.

Study Overview
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Brief Summary
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An interventional study on the effects of repeated trunk flexion exposure on trunk neuromuscular properties.

Detailed Description
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An interventional study will include 16 healthy young adults. All participants will complete a 60-min protocol of intermittent trunk flexion. Measurements of trunk neuromuscular properties will be performed prior to and following the 60-min protocol.

Official Title
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Effects of Repeated Trunk Flexion on Trunk Neuromuscular Properties.

Conditions
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Occupational Exposure

Intervention / Treatment
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* Other: Repeated trunk flexion


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Physically active at least 3 hours a week Exclusion Criteria: Low back pain in the past 6 months History of chronic low back pain History of spinal or pelvic operation Hypermobility, more than 4 points on Beighton scale Cardiovascular or systemic diseases Pregnancy

Ages Eligible for Study
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Minimum Age: 18 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: Basic Science
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Intermittent trunk flexion<br>60-min intermittent trunk flexion protocol. | Other: Repeated trunk flexion<br>* A 60-min intermittent trunk flexion protocol. Participants will sit on a standard height sit, with their knees bent at approximately 90° with their hands crossed on their chest. They will perform 40 sets of 60 s of maintaining a flexed position, interspersed with 30 s of rest. Participants will achieve the flexed position by tilting the pelvis posteriorly and leaning forward. During rest, participants will sit up straight without leaning on the support.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in muscle stiffness | Muscle stiffness will be measured in prone lying using ultrasound-based shear wave elastography. Erector spinae and multifidus muscle stiffness will be expressed as the shear modulus value in kilopasquals. | 90 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in range of motion | Trunk flexion range of motion will be evaluated using inertial measuring units during bending in standing position. | 90 minutes | 
| Change in length of the spine | The length of spine will be measured on a custom-developed stadiometer, with the participants in a seated position. | 90 minutes | 
| Change in muscle activity | Muscle activity will be measured using electromyography during standing. | 90 minutes | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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bending, load, stiffness, elastography, deformation