¹National Research Centre for the Working Environment, Copenhagen, Denmark

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Introduction: High physical exposures increase the risk of pain and sickness absence, and may contribute to construction workers – such as carpenters and masons – leaving the labour market prematurely due to excessive physical workload. These occupations often involve repetitive movements, heavy lifting, and awkward postures, all of which elevate the risk of work-related musculoskeletal disorders and early labour market exit. To support a sustainable working life, effective ergonomic initiatives are needed. Exoskeletons – wearable devices designed to reduce physical load workload – represent a potential solution, particularly when used during high-strain work activities. The aim of this study was to evaluate the effect of exoskeleton use on muscle activity and kinematics during construction work.

Methods: This field study employed a randomized cross-over design with repeated measures to evaluate the effect of exoskeleton use on muscle activity and kinematics among two construction occupations: carpenters performing overhead work and masons doing in bricklaying. The study was conducted at multiple construction sites in Denmark from September 2022 to August 2023. A total of 40 participants (22 carpenters and 18 masons) were included. Carpenters used a shoulder-support exoskeleton (Hilti EXO-01), while masons used a back-support exoskeleton (Laevo V2.57).

After a two-week familiarization period with exoskeleton use during regular work tasks, each participant took part in an in-field test session. This included completing a usability questionnaire, being fitted with measurement devices (surface electromyography and inertial measurement units (Xsens)), and performing maximal voluntary isometric contractions. Participants then carried out their usual work tasks – ceiling installation and bricklaying for carpenters and masons, respectively – with and without the exoskeleton in a randomized order, while muscle activity and body posture were continuously monitored in real time. Qualitative interviews were also conducted with participants from both occupations to assess their experiences and perspectives on exoskeleton use.

Preliminary results: Preliminary findings indicate that exoskeleton use among carpenters led to reduced shoulder muscle activity and was generally well received, suggesting potential ergonomic benefits.

In contrast, exoskeleton use among masons led to increased muscle activity in the low-back muscles. Furthermore, the masons reported the exoskeleton as uncomfortable and expressed limited willingness to continue using it.

These results highlight the importance of task-specific assessments and user-centered evaluation prior to implementation. Final results, including key qualitative findings, will be presented at PREMUS 2025.