Evaluation of Trunk Assistance Exoskeleton

NCT07084974 | Recruiting

• 1 other identifier: 502_IRSST_Exo
• Study Type: interventional
• Target: 20
• Locations: 1 country
• Sites: 1

Brief Summary

The goal of this interventional study is to evaluate the effect of three different designs of trunk assistance exoskeletons on cumulative lumbar load, trunk extensors' muscular fatigue and comfort in healthy volunteers. The main questions it aims to answer is: will exoskeletons reduce muscle fatigue and cumulative lumbar load. Participants will :

• get each exoskeletons adjusted and then practice the lifting task and measurement sequence in a first session
• perform a lifting task for 4 blocks of 20 minutes on different sessions for each exoskeleton, another session is performed without assistance.

Conditions

Exoskeleton Device

Keywords

exoskeleton; trunk assistance; cumulative lumbar load; muscular fatigue; lifting task; comfort; acceptability

Outcome Measures

Primary Outcomes (3)

• Change in spinal compression

  Stadiometer measurements require an electronic comparator (Mitutoyo; model 543-730B) mounted on a height-adjustable structure that allows alignment with the longitudinal axis of the spine. To measure spinal compression, the participant should position themselves face down against the wall, feet shoulder-width apart (template on the floor), knees fully extended, arms at their sides, and the following points in "light" contact with the wall: forehead, nose, pelvis (or navel), and toes (without shoes, with socks). The assessor will be asked to take the measurements (10 measurements) at the end of expiration, where they will be asked to hold their breath for 2-3 seconds. The baseline for the lifting task sessions is measured before all lifting task blocks. This measurement, expressed in millimeters, reflects only the vertical position of the electronic comparator. Measure = Mean after Block X - Session's baseline mean(before block 1).

  For each lifting task session, change between session's baseline(immediately before the first lifting task block) and immediately after each lifting task block

• Change in muscular exertion perception

  Participants score their muscular exertion perception in 5 muscle groups (quadriceps, hamstrings, hip extensors, lumbar extensors, thorax extensors) on the Borg CR-10 scale. The baseline for the lifting task sessions is measured before all lifting task blocks. There are 12 levels to this scale(Minimum=0(No exertion) maximum=10(maximal exertion), all integer values, 0.5 is also an option.

  For each lifting task session, change between session's baseline(immediately before the first lifting task block) and immediately after each lifting task block

• Change in maximal lifting strength

  Maximal lifting strength is assessed by measuring pulling force on a bar at knee level with a strain gauge. The handle is held firmly by both hands. Participants were asked to bend at the hips and knees so as to keep an extended lower back during the trials, similar to a deadlifting position. During each trial, participants were asked to progressively pull harder on the bar without jerking for 5 seconds. The maximal value expressed in newtons during each trial was used. The baseline measurement is the mean of 3 trials with a 2 minute pause in between trials. Only 1 trial was performed after the last lifting block so as to better assess muscular fatigue by limiting time for recovery.

  For each lifting task session, change between session's baseline(immediately before the first lifting task block) and immediately after the last lifting task block

Secondary Outcomes (10)

• Exoskeleton assistance score

  For each lifting task session where the participant wore a trunk assistance exosqueleton, immediately after the last lifting task block

• Number of cycles with parasitic forces score

  For each lifting task session where the participant wore a trunk assistance exosqueleton, immediately after the last lifting task block

• Magnitude of parasitic forces score

  For each lifting task session where the participant wore a trunk assistance exosqueleton, immediately after the last lifting task block

• Number of cycles with restriction of movement

  For each lifting task session where the participant wore a trunk assistance exosqueleton, immediately after the last lifting task block

• Magnitude of restriction of movement

  For each lifting task session where the participant wore a trunk assistance exosqueleton, immediately after the last lifting task block

Study Arms (1)

Repeated measures intervention group

EXPERIMENTAL

Participants will perform 5 different intervention sessions: An adjustment and practice session which is always performed first, then participants will performed 4 lifting tasks sessions in randomized order: * No trunk assistance session * Uplift Lite exoskeleton session * Biolift exoskeleton session * Laevo Flex exoskeleton session During each lifting task session, participants will perform 3 blocks of 20 minutes of the lifting task. The lifting task is a box transfer tasks from the ground to a table adjusted at hip height. The task rythm is 7 cycles per minute. The box weight is equivalent to 10% of their maximal lifting strength. The handles of the box are positioned at 28 cm above the bottom of the box. Total session duration is about 3 hours for all sessions. Participants will have between 4 and 14 days of rest in between each sessions.

Device: Adjustment and practice session; Device: No trunk assistance; Device: Uplift Lite exoskeleton; Device: Biolift exoskeleton; Device: Laevo Flex exoskeleton

Interventions

Adjustment and practice session DEVICE

During the adjustment and practice session, participants will perform the lifting task with each exoskeleton after they are properly fitted. They will also perform the measurement sequence as to limit learning effects during lifting task sessions. The lifting task is a box transfer tasks from the ground to a table adjusted at the participant's hip height. The task rhythm is 7 cycles per minute. The box weight is equivalent to 10% of their maximal lifting strength. Total session duration is about 3 hours.

Repeated measures intervention group

No trunk assistance DEVICE

This lifting task session is performed without any trunk assistance exoskeleton. Participants perform 3 blocks of 20 minutes of the lifting task. The lifting task is a box transfer tasks from the ground to a table adjusted at the participant's hip height. The task rhythm is 7 cycles per minute. The box weight is equivalent to 10% of their maximal lifting strength. Total session duration is about 3 hours.

Repeated measures intervention group

Uplift Lite exoskeleton DEVICE

This lifting task session is performed with the Mawashi Uplift Lite trunk assistance exoskeleton. Participants will perform 3 blocks of 20 minutes of the lifting task. The lifting task is a box transfer tasks from the ground to a table adjusted at the participant's hip height. The task rhythm is 7 cycles per minute. The box weight is equivalent to 10% of their maximal lifting strength. Total session duration is about 3 hours.

Repeated measures intervention group

Biolift exoskeleton DEVICE

This lifting task session is performed with the Biolift trunk assistance exoskeleton. Participants perform 3 blocks of 20 minutes of the lifting task. The lifting task is a box transfer tasks from the ground to a table adjusted at the participant's hip height. The task rhythm is 7 cycles per minute. The box weight is equivalent to 10% of their maximal lifting strength. Total session duration is about 3 hours.

Repeated measures intervention group

Laevo Flex exoskeleton DEVICE

This lifting task session is performed with the Leavo Flex trunk assistance exoskeleton. Participants perform 3 blocks of 20 minutes of the lifting task. The lifting task is a box transfer tasks from the ground to a table adjusted at the participant's hip height. The task rhythm is 7 cycles per minute. The box weight is equivalent to 10% of their maximal lifting strength. Total session duration is about 3 hours.

Repeated measures intervention group

Eligibility Criteria

• Age: 18 Years - 65 Years
• Sex: male
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Being able to communicate in french

You may not qualify if:

• Back pain in the last year
• Back pain for more than a week in the years prior
• Musculoskeletal injury in the last year
• Trunk musculoskeletal system surgery in the last year
• Scoliosis diagnostic
• Systemic illness, degenerative disease or syndrome related to the trunk musculoskeletal or nervous system
• Body mass index over 35 kg/m\^2
• History of neurological damage
• Any contraindication to the practice of physical activity
• Incapacity to perform the lifting task at the specified rythm
• Medication with a negative impact on balance

Sponsors & Collaborators

• TOPMED: lead
• Institut de Recherche Robert-Sauvé en Santé et en Sécurité du Travail: collaborator
• Natural Sciences and Engineering Research Council, Canada: collaborator

Study Sites (1)

TOPMED

Québec, Quebec, G1S1C1, Canada

RECRUITING

Central Study Contacts

Edith Martin, Ph.D

CONTACT

4187801301; emartin@topmed.ca

Gabriel Diamond Ouellette, Ph.D

CONTACT

gdiamondouellette@topmed.ca

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: PREVENTION
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: All participants will begin by the adjustement and practice session. The order of the 4 other interventions(No trunk assistance, and the 3 exoskeletons: Uplift Lite, Biolift and Laevo Flex) will be randomized in between participants to reduce sequence effects.

Study Record Dates

• First Submitted: July 17, 2025
• First Posted: July 25, 2025
• Study Start: June 4, 2025
• Primary Completion: November 1, 2025
• Study Completion: May 1, 2026
• Last Updated: July 25, 2025

Record last verified: 2025-07

Data Sharing

• IPD Sharing: Will not share

Locations

CA (1)