Work-related musculoskeletal disorders are common, especially among women performing repetitive overhead tasks. In a randomized 2 × 2 crossover study with 14 female participants, we investigated the effects of a passive upper-body exoskeleton during an overhead precision task, involving the tightening of 20 bolts into a sensor-based workstation, while muscle activation, task performance, and usability were assessed. The results showed significant reduced M. Trapezius muscle activations during arm lowering (p = .041, 73%), and lower target accuracy (p < .001, 100%) when using the exoskeleton. Subjective strain in the shoulders was significantly lower when using the exoskeleton (p = .035, 15%). The usability was rated as “unacceptable”, with users criticizing the complexity and learning effort. While the exoskeleton reduced muscle load, its mechanical limitations impaired precision and usability, especially for women. These results highlight the importance of sex-specific, ergonomic, and adaptive designs to improve exoskeleton effectiveness and acceptance.
