Retail workers standing and walking activities assessment

Introduction: Retail shop work often requires prolonged standing postures, especially when attending tasks related to cash. Previous studies suggest a maximum holding time of 120 seconds valid for 95% of adult healthy workers to avoid short term discomfort and long term musculoskeletal disorders with reference to unsupported static standing. Nevertheless the topic is still debated, since no method of measure seems reliable. Aim: The aim of the study is measuring the time spent by retail workers within static or dynamic standing postures. Methods: Flexiforce pressure sensors positioned under the forefoot and heel of both feet and linked to a digital/analog recorder were chosen to measure the following parameters: pressure from each sensor, number of steps, estimated distance walked, number of isolated steps, duration of static postures not alternated by small movements. 21 workers from 3 top-selling retail stores in downtown Milan were tested during the whole workday chosen from the usual highest and lowest selling days. Results: The mean walking time resulted 22,4%, the mean distance 825,7 m/hours, the mean number of steps was 4,1, the mean static time was 44,4% while the mean time spent on short steps was 32,5%. Only once the 120 seconds static threshold was exceeded. ANOVA was non-significant comparing different tasks scheduling. Discussion: Within the frame of this on-the-field observational design the retail shop work can hardly be defined as static job. In fact to avoid static postures risks the management forced 2 hours rotational tasks shifts between static standing activities and other retail tasks, such as folding garments and providing help to clients. As a result the mean 4 hours distance walked was greater than 2 kilometers, simply avoiding exclusive static standing tasks. This measurement method seems more precise than previous ones in describing prolonged standing and very slow walking.