Occupational Exposure
Conditions
Brief summary
In this study the LiftSuit version 2.0 designed by Auxivo AG will be used. The LiftSuit is a soft wearable device that is designed to support workers perform physically demanding tasks including repetitive lifting and working in forward leaning positions. It is put on like a backpack and attached to the body using fabric bands and cuffs. Besides soft fabric parts the LiftSuit contains elastics elements. The elastic elements can be flexibly exchanged by the experimenter. For this experiment elastic elements of known stiffness will be hooked into the fabric frame.
Detailed description
In a first step participants will try on the LiftSuit exoskeleton and adjust it to their body under supervision of the experimenter. When the LiftSuit exoskeleton is adjusted to the participant it is taken off to allow placement of sensors. The sensors used to record heart rate (Polar H9 heart rate monitor, Polar Electro Europe AG, Germany), muscle activity from 8 muscles in the back and hip region (Delsys Trigno, Delsys Europe, United Kingdom) and movement kinematics (OptiTrack motion capture system, NaturalPoint Inc., USA) will be placed by the experimenter (or participant him/herself). To verify that the electromyography sensors, are working and to obtain normalization values, participants will be instructed to conduct maximal voluntary contractions of each muscle that are being recorded. If needed single sensors can be replaced. After this the exoskeleton will be put back on.
Interventions
DEVICEPlacebo LiftSuit Exoskeleton
The LiftSuit is a soft passive wearable device that is designed to support the hip and back muscles during forward leaning and lifting. It exerts it function through Elastic Energy Storages (EES). In this condition the EES are removed from the device to create a placebo device.
DEVICELiftSuit Exoskeleton (low support level)
The LiftSuit is a soft passive wearable device that is designed to support the hip and back muscles during forward leaning and lifting. It exerts it function through Elastic Energy Storages (EES). EES of different three different levels of stiffness (low, medium, high stiffness) will be used.
DEVICELiftSuit Exoskeleton (medium support level)
The LiftSuit is a soft passive wearable device that is designed to support the hip and back muscles during forward leaning and lifting. It exerts it function through Elastic Energy Storages (EES). EES of different three different levels of stiffness (low, medium, high stiffness) will be used.
DEVICELiftSuit Exoskeleton (high support level)
The LiftSuit is a soft passive wearable device that is designed to support the hip and back muscles during forward leaning and lifting. It exerts it function through Elastic Energy Storages (EES). EES of different three different levels of stiffness (low, medium, high stiffness) will be used.
Sponsors
Auxivo AG
Swiss Federal Institute of Technology
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
PREVENTION
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 65 Years
Healthy volunteers
Yes
Inclusion criteria
* Included will be volunteers of both sexes within working age (18 to 65 years).
Exclusion criteria
* Participants will be excluded if they cannot perform the tasks (squat lifting and forward leaning) due to physical limitations. Furthermore, people who report acute joint or muscle pain or stiffness, or a self-reported history of such problems will be excluded.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in muscle activity of hip extensor muscles (placebo comparator - low support experimental intervention) | 2 hours | An elastic band placed external to the body parallel to the spine and over the hip joint is likely to support the muscles that extend the hip and back. Less hip extensor muscle (m. gluteus maximus, hamstrings) activity is expected in LiftSuit conditions compared to the placebo comparator condition. |
| Change in muscle activity of back extensor muscles (placebo comparator - low support experimental intervention) | 2 hours | An elastic band placed external to the body paralell to the spine and over the hip joint is likely to support the muscles that extend the hip and back. Less back muscle activity (erector spinae at lumbar and thoracic level) is expected in LiftSuit conditions compared to the placebo comparator condition. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in muscle activity of hip extensor muscles related to stiffness level of the Elastic Energy Storages (low, medium, high stiffness). | 2 hours | A reduction in muscle activity is expected. This reduction is expected to be related to the stiffness level of the EES. With high stiffness, leading to more support, leading to less muscle activity. |
| Change in muscle activity of back muscles related to stiffness level of the Elastic Energy Storages (low, medium, high stiffness). | 2 hours | The reduction in muscle activity is expected to be related to the stiffness level of the EES. With high stiffness, leading to more support, leading to less muscle activity. |
Other
| Measure | Time frame | Description |
|---|---|---|
| Change in muscle activity of abdominal muscles (placebo comparator - experimental intervention) | 2 hours | An elastic band placed external to the body over the hip joint is likely to support the muscles that extend the hip. It could be that this setup might heightened levels of activity in the abdomen. |
| Change in hip angle kinematics (placebo comparator - experimental intervention) | 2 hours | Changed forces around the hip joint might influence movement kinematics of this joint. Changes in position and acceleration of the joint angle will be calculated. |
Countries
Switzerland
Outcome results
None listed