RESUMO
Sit-stand workstations are growing in popularity, however limited guidelines exist regarding optimal schedules of sitting and standing. This was the first known study to observe sit-stand workstation schedules when postural change is based on maintaining musculoskeletal discomfort within 'acceptable' levels. Fourteen healthy adults new to sit-stand workstations completed computer-based work at a sit-stand desk for half a workday. Participants changed between standing and sitting postures each time discomfort reached the maximum acceptable threshold. On average, the amount of standing and sitting was greatest in the first standing (median 40 minutes, interquartile range 40 minutes) and sitting (median 30 minutes, interquartile range 115 minutes) bouts. Average durations spent standing and sitting were lower in all consecutive bouts. Stand-sit ratios indicated an equal amount of standing to sitting or somewhat less standing. The schedules had substantial inter-participant variability. Future studies should consider that optimal schedules may vary with regard to time and be individual-specific.
Refined guidelines are needed regarding effective use of sit-stand workstations. This study proposed a novel method of investigating potentially optimal schedules, in which postural change was based on reaching a threshold of musculoskeletal discomfort. The findings suggest that an optimal schedule may vary with time and be individual-specific. Abbreviations: BMI: body mass index; Borg CR-10 scale: Borg Category Ratio-10 scale; IQR: interquartile range; LMD questionnaire: the localised musculoskeletal discomfort questionnaire; MHT: maximum holding time; SD: standard deviation.