Author(s): SCHMITTER, F., BÜCHEL, D., BRAUN, I., ARGUBI-WOLLESEN, A., WOLLESEN, B. , Institution: INSTITUTE FOR MOVEMENT THERAPY AND MOVEMENT-ORIENTED PREVENTION AND REHABILITATI, Country: GERMANY, Abstract-ID: 769

INTRODUCTION:
Recent studies indicated that exoskeletons can lower back muscle activity by approximately 15-30% during lifting or forward bending tasks (Ali et al., 2021). However, they may also alter attentional control and sensorimotor integration, due to cognitive-motor interference (CMI), especially when individuals are required to perform multiple tasks in occupational settings (Gräf et al., 2024). Therefore, the aim of the study is to synthesize the current evidence on the neurophysiological, neurocognitive, musculoskeletal, and biomechanical responses occurring when performing occupational tasks with back- and shoulder-supporting exoskeletons.
METHODS:
A scoping review was conducted according to the PRISMA-ScR guidelines. Databases including PubMed, Embase, and Web of Science were searched for studies involving adults performing occupational or simulated work tasks with back- or shoulder-support exoskeletons. Eligible studies reported at least one neurophysiological or cognitive outcome alongside musculoskeletal or biomechanical measures. Data were charted by outcome domain and methodological quality was assessed using the KMET (Kmet et al., 2004) tool.
RESULTS:
A total of eight studies published between 2021 and 2025 met the inclusion criteria, comprising a total of 139 participants (mean ages ranging from 19.6 to 34.3 years; 55.6% male, 43.7% female). The overall methodological quality was moderate to high (KMET scores: 18–24/26). Lower scores were primarily related to small sample sizes. Six studies reported a reduction in muscle activity in the primary supported region. Two studies reported reduced lumbar compression and shear forces during lifting. Three studies observed behavioral dual-task effects, including impaired auditory counting accuracy, reduced visual performance, and increased error rates during serial subtraction. Three studies assessed neurophysiological outcomes using functional near-infrared spectroscopy (fNIRS), all reported increased prefrontal activation and altered fronto-motor connectivity during exoskeleton-assisted tasks.
CONCLUSION:
Although occupational exoskeletons provide biomechanical benefits, evidence from six studies (three neurophysiological and three behavioral) indicates increased cognitive demands during complex or multitasking work whilst using exoskeletons. Therefore, it is important to evaluate whether using exoskeletons suggests causality by unintended CMI that could affect task performance, safety, and usability. Existing evidence highlights the need to expand existing support models to incorporate CMI for a more holistic understanding of human-exoskeleton performance.

REFERENCES:
Ali et al. (2021). Frontiers in Bioengineering and Biotechnology.
Gräf et al. (2024). Frontiers in Neurology.
Kmet et al. (2004). Alberta Heritage Foundation for Medical Research.