Manual material handling in the supermarket sector. Part 1: Joint angles and muscle activity of trapezius descendens and erector spinae longissimus

Work-related musculoskeletal disorders are highly prevalent in the supermarket sector with manual material handling being one of most commonly identified occupational risk factors. This cross-sectional study applied inertial motion capture and electromyography (EMG) to measure full-body kinematics muscle activity trapezius descendens erector spinae longissimus during 50 tasks performed by 17 workers two supermarkets. The bread cucumbers high shelf heights showed highest (from 47% 59% peak normalized EMG), while bananas as well lifting milk, from low positions 71%). Twenty-two involved flexing shoulders trunk more than 90° 50°, respectively. Based on these results, several practices supermarkets should be reconsidered reduce physical work demands. • Field analysis common activities Cucumbers required muscular efforts for shoulder/neck. Bananas, lower back. Large proportion analyzed undesirable working postures. Handling