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Introduction: Hospital beds are among the heaviest medical devices that regularly need to be moved by staff. Moving the beds is therefore often perceived as burdensome and is associate-ed with a high prevalence of musculoskeletal disorders. Bed movers were developed to reduce this strain. These motorized systems attach to the bed and are controlled by the hospital staff using either a drawbar, a joystick while walking, or a joystick while standing on a platform. Earlier studies (Daniell et al., 2014; Guo et al., 2017) have already demonstrated in their studies that specific bed movers can reduce muscle activity. This study investigates the effects of three control types on muscle activity compared to manual pushing.

Methods: Ten nursing staff members moved a hospital bed manually and using three different bed movers over a 200 m course with five 90° turns, one 180° turn, and a 10 m ramp (3.5% gradient). Each method was repeated three times in a randomized order. Sur-face electromyography (sEMG) recorded the bilateral activity of the anterior deltoid, descending trapezius, latissimus dorsi, and erector spinae, normalized to maximal voluntary isometric contraction (MVIC). Repeated-measures ANOVA (α = .05) and Bonferroni corrected post-hoc tests were performed.

Results: All bed movers significantly reduced muscle activity compared with manual pushing. The drawbar system reduced activity by 42%, the walking joystick by 54%, and the platform joystick by 74%. All systems significantly reduced anterior deltoid activity. Both joystick-operated movers also reduced descending trapezius activity, while only the platform mover significantly reduced erector spinae activity. The smallest reductions were seen with the drawbar mover (27% in erector spinae, 13% in trapezius).

Discussion: Differences in handling led to differences in muscle activation. With the walking joystick, users had to counterbalance manually with one arm, increasing deltoid activity. The drawbar system caused backward rotation and pulling, resulting in unilateral strain that reduced trunk relief. Standard deviations were high due to muscle crosstalk, contralateral activation, and a heterogeneous sample (6 males, 4 females; 36.8 ± 11.2 years; 79.6 ± 13.8 kg). Although the course was hospital-based, it only partly reflected daily routines. Future research should investigate more realistic tasks, such as navigating elevators or patient rooms. Differences in relief should be considered when selecting bed movers, especially for occupational health or rehabilitation programmes.

Conclusion: Compared to manually pushing hospital beds, the use of Bed Movers reduces the physical strain on nursing staff. The different operating concepts lead to varying muscle relief. When purchasing Bed Movers, this should be considered, particularly if they are intended for use in employee rehabilitation.