Relationships Between Muscle Activity, Soft Tissue Changes, and Movement Strategies in Individuals With Chronic Low Back Pain (E-LBP)

Study of the Relationships Between Muscle Activity, Soft Tissue Changes, and Movement Strategies in Individuals With Chronic Low Back Pain, in Order to Support Their Return to Sport and Physical Activity

This study aims to explore, in patients with chronic non-specific low back pain (cnsLBP), the relationships between lumbar muscle activity, structural and morphological characteristics of the paraspinal muscles, and movement strategies, during a functional, ecological task: walking. To do this, we will compare a group of cnsLBP patients with a group of asymptomatic subjects, combining several types of measurements taken at different walking intensities: spinal kinematics (movement strategies), electromyographic activity of the lumbar muscles, and structural parameters of the paraspinal muscles (stiffness and thickness). The objective is twofold: first, to identify any significant differences between cnsLBP patients and healthy subjects on these combined parameters; second, to explore the interactions between these three dimensions (muscle activity, muscle structure, movement strategy) in order to better understand their relationships with pain and with how CNSLBP functions during physical activity. This multidimensional, ecological approach could also help identify subgroups within the cnsLBP population, reflecting the clinical heterogeneity already documented in the literature. Ultimately, the expected results will contribute to a better understanding of the biomechanical and neuromuscular mechanisms involved during physical activity in these patients, and will provide objective elements to help individualize physical activity recommendations according to each patient's profile.

Study Overview

• Status: Not yet recruiting
• Conditions: Non-specific Chronic Low Back Pain
• Intervention / Treatment: Other: Supervised Progressive Walking Test

• Study Type: Interventional
• Enrollment (Estimated): 60
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Léo Denouël, PhD Student; Phone Number: +33 (0) 681768024; Email: leo.denouel@univ-rennes2.fr
• Study Contact Backup: Name: Armel Crétual, Professor; Phone Number: +33 (0) 290091588; Email: armel.cretual@univ-rennes2.fr

Study Locations

• France
  • Rennes, France, 35000
    • University of Rennes 2
    • Sub-Investigator: Mathieu Ménard, PhD
    • Contact: Léo Denouël, PhD Student; Phone Number: +33 (0) 681768024; Email: leo.denouel@univ-rennes2.fr
    • Contact: Armel Crétual, Professor; Phone Number: +33 (0) 290091588; Email: armel.cretual@univ-rennes2.fr
    • Sub-Investigator: Nolwenn Fougeron, PhD
    • Sub-Investigator: Diane Haering, PhD
    • Sub-Investigator: Armel Crétual, Professor
    • Sub-Investigator: Olivier Roze, MD
    • Principal Investigator: Emilie Leblong, MD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

- Inclusion criteria for CNSLBP participants

Adult aged 18 to 65 years (inclusive) Have freely given written informed consent Present with pain located between the thoracolumbar junction and the inferior gluteal fold, with or without pain in one or both legs This pain must have been present for more than 12 weeks, on a daily or near-daily basis (at least 4 days out of 7) Participants must not be undergoing any treatment, or must have been on a stable analgesic treatment for at least 2 weeks prior to inclusion in the study Must not have performed, in the 72 hours preceding participation in the study, any unusual intense physical activity (e.g., carrying a heavy load (> 25 kg), sporting activity) likely to transiently alter muscle activity or the mechanical properties of the tissues studied

- Non-inclusion criteria for CNSLBP participants

Known contraindications or limitations to walking Cardiovascular risk factors (uncontrolled high blood pressure, poorly controlled diabetes or diabetes with complications, severe untreated dyslipidemia), or heart disease contraindicating physical activity Ongoing litigation following a workplace accident

Any form of specific low back pain, with an identified cause or secondary to an underlying condition, including in particular:

Pain related to a cancer diagnosis Spinal cord or cauda equina symptoms (pyramidal signs, coordination disorders, motor or sensory deficits, sphincter disorders, etc.) Pain following an infection (night sweats, fever, chills, intravenous drug abuse, immunodeficiency, recent surgery, urinary or skin infection, etc.) Recent or pathological fractures (road traffic accidents, history of osteoporosis, chronic corticosteroid use, advanced age, unexplained weight loss, fatigue, history of cancer, etc.) Inflammatory rheumatism (ankylosing spondylitis, rheumatoid arthritis, or other rheumatic diseases) Vascular problems (cold feet, diminished peripheral arterial pulse, etc.) Disabling radicular irradiation, at the investigator's discretion Participants must not have undergone an intensive rehabilitation program within the last 3 months, nor received physiotherapy, manual therapy, acupuncture, or any other type of manual medicine or bodywork treatment outside their usual care, within the 4 weeks preceding inclusion Severe, unstabilized psychiatric condition Person presenting with a pathology or orthopedic disorder affecting locomotion Recent spinal surgery (< 3 months before the inclusion visit) Systemic corticosteroid use, or corticosteroid injection at the lumbar spine, within the last 3 months Muscle relaxant use in the week preceding the experiment

- Inclusion criteria for asymptomatic participants

Adult aged 18 to 65 years (inclusive) Have freely given written informed consent Person presenting no form of low back pain and matching the age and male-to-female ratio characteristics of the CNSLBP group*

In accordance with Article L1121-8-1 of the French Public Health Code, participants must be affiliated to, or beneficiaries of, a social security scheme

To ensure correspondence in terms of age and sex ratio between the CNSLBP group and the healthy group, the frequency of age and gender categories among CNSLBP participants will be used to build, by matching, the group of healthy participants.

- Non-inclusion criteria for asymptomatic participants

Person reporting an ongoing chronic pain complaint or a history of significant chronic pain (≥ 4/10 for at least 6 months) (HAS, 2019) Person unable to perform the walking tasks studied without excessive discomfort or fatigue

- Non-inclusion criteria common to CNSLBP and asymptomatic participants

Known contraindications or limitations to walking Cardiovascular risk factors (uncontrolled high blood pressure, poorly controlled diabetes or diabetes with complications, severe untreated dyslipidemia), or heart disease contraindicating physical activity Severe, unstabilized psychiatric condition Person presenting with a pathology or orthopedic disorder affecting locomotion

(*) Persons referred to in Articles L. 1121-5 to L. 1121-8 and L. 1121-12 of the French Public Health Code:

Pregnant, parturient, or breastfeeding woman Person deprived of liberty by judicial or administrative decision Person hospitalized without consent and not subject to a legal protection measure, and person admitted to a healthcare or social institution for purposes other than research Person subject to an exclusion period for another study Adult subject to a legal protection measure (guardianship, conservatorship, or court protection), or adult unable to express consent and not subject to a protection measure

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Non-Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Non-specific Chronic Low Back Pain participants; Participants underwent a single assessment session including lumbar muscle ultrasound imaging, functional movement task analysis and a walking test. No therapeutic intervention was administered.	Other: Supervised Progressive Walking Test; After a warm-up period on the treadmill, the test involves walking, starting at a speed of 3 km/h and increasing the speed by 0.5 km/h every 2 minutes, up to a maximum of 7 km/h. The speed of 7 km/h is a target speed and is not mandatory.
Experimental: Asymptomatic participants; Participants underwent a single assessment session including lumbar muscle ultrasound imaging, functional movement task analysis and a walking test. No therapeutic intervention was administered.	Other: Supervised Progressive Walking Test; After a warm-up period on the treadmill, the test involves walking, starting at a speed of 3 km/h and increasing the speed by 0.5 km/h every 2 minutes, up to a maximum of 7 km/h. The speed of 7 km/h is a target speed and is not mandatory.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in muscle stiffness of the erector spinae and multifidus muscles between rest and after physical activity	Change in muscle stiffness, measured by shear modulus using shear-wave elastography, of the erector spinae and multifidus muscles, between rest and after physical activity.	As the study consists of a single session, the time frame is between the pre-walking-test and post-walking-test assessments.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Ultrasound morphological measurements	Measurement of the cross-sectional area and thickness-as determined by ultrasound-of the erector spinae and multifidus muscles at rest.	Data were collected during the experimental session.
Electromyographic activity	Lumbar muscle activations during three-dimensional lumbar movements and while walking	Data were collected during the experimental session.
Kinematics	The kinematics of the lumbopelvic-femoral complex (segmental velocity and acceleration, joint angles) during three-dimensional movements and while walking.	Data were collected during the experimental session.
General data	Age, sex, height, weight, body mass index, and socioeconomic status are recorded.	Data were collected during the experimental session
Impact, effort, and sensations during the walking experience	Intensity of pain experienced, measured using a numerical rating scale at rest and during activity. Perceived exertion during walking on a treadmill, measured using the Borg CR-10 scale. Heart rate recorded using a Garmin® HRM heart rate monitor. Time, distance, and speed achieved during the walking task	Data were collected during the experimental session
Physical function	Patients' physical function is assessed using the Oswestry Disability Index (ODI).	Data from the questionnaire were collected during the experimental session, or shortly before (between 1 and 7 days beforehand)
Pain intensity and location	The intensity of pain experienced by participants on the day of the test, as measured by a numerical rating scale, and the location of the pain, as determined by the Pain Drawing test.	Data were collected during the experimental session
Daily impact of pain	The daily impact of pain (daily activities, work, leisure, anxiety and depression, social life) is assessed using the Dallas Self-Report Questionnaire (DRAD).	Data from the questionnaire were collected during the experimental session, or shortly before (between 1 and 7 days beforehand)
Quality of life health-related	Health-related quality of life is assessed using the SF-12 questionnaire (SF-12)	Data from the questionnaire were collected during the experimental session, or shortly before (between 1 and 7 days beforehand)
Physical activity and sedentary behavior	Participants' physical activity and sedentary behavior are assessed using the French version of the Global Physical Activity Questionnaire (GPAQ).	Data from the questionnaire were collected during the experimental session, or shortly before (between 1 and 7 days beforehand)
Kinesiophobia	Fear of physical injury related to movement is assessed using the Tampa Scale for Kinesiophobia (TSK).	Data from the questionnaire were collected during the experimental session, or shortly before (between 1 and 7 days beforehand)
Anxiety and depressive disorders	Screening for anxiety and depressive disorders is performed using the Hospital Anxiety and Depression Scale (HAD).	Data from the questionnaire were collected during the experimental session, or shortly before (between 1 and 7 days beforehand)
Validity of ultrasound measurements	The validity of ultrasound measurements is assessed by the intra-operator repeatability of ultrasound measurements.	Data were collected during the experimental session

Collaborators and Investigators

• Sponsor: University of Rennes 2
• Investigators: Principal Investigator: Emilie Leblong, MD, Fondation Saint Helier, 35043 Rennes, France

Study record dates

Study Major Dates

• Study Start (Estimated): September 1, 2026
• Primary Completion (Estimated): September 1, 2028
• Study Completion (Estimated): September 1, 2028

Study Registration Dates

• First Submitted: September 2, 2026
• First Submitted That Met QC Criteria: September 2, 2026
• First Posted (Actual): September 8, 2026

Study Record Updates

• Last Update Posted (Actual): September 8, 2026
• Last Update Submitted That Met QC Criteria: September 2, 2026
• Last Verified: August 1, 2026

More Information

Terms related to this study

• Keywords: physical activity; walking; Non-specific Chronic Low Back Pain; muscular activity; biomechanical assessment; nscLBP; muscular stiffness; movement Strategies
• Additional Relevant MeSH Terms: Behavior; Motor Activity
• Other Study ID Numbers: 2026-A00042-49

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No