Passive lower-limb exoskeletons in industry: A review of “Chairless Chairs” for reducing fatigue and musculoskeletal strain

Study aim The aim of this systematic review is to categorize and evaluate lower-limb exoskeletons, including commercial and research-based models, to identify the most effective designs for alleviating musculoskeletal strain and fatigue in industrial settings. Material and methods A comprehensive search of PubMed, ScienceDirect, and Scopus yielded 87 studies; 17 of these met the inclusion criteria (published within the last 10 years in the English language and available as a full text). Data on exoskeleton type, design, and performance outcomes were extracted. Results Passive exoskeletons, particularly “chairless chairs,” such as NOONEE and LegX, were the most effective, reducing lower-limb strain by up to 64 and 56%, respectively. Research prototypes demonstrated similar outcomes, with some achieving 83% reduction in muscle activity. Reported benefits included lower perceived discomfort, improved usability, and reduced contact pressure. Conclusion Passive lower-limb exoskeletons are a feasible and effective ergonomic intervention for tasks involving prolonged standing in industrial settings. Their portability, ease of use, and capacity to reduce muscular load make them especially suitable for widespread adoption in the workplace. Future research should evaluate long-term health, safety, and productivity outcomes in real-world industrial environments.