A study was made of work conditions suspected of being responsible for a greater prevalence of musculoskeletal disorders among 33 bricklayers. A standardized questionnaire was used to confirm a high 12-month prevalence of 73% for the low back and about 20% for the upper limbs. Physical work load was studied with the use of heart rate recordings and posture analyses. According to the heart rate data, the work load was 'moderatley heavy' (300 W). A diagnostic analysis identified work postures that could be considered as imposing a heavy strain on the musculoskeletal system. The risk associated with these postures was investigated with biomechanical models. This analysis procedure made possible elaborate ergonomic solutions that reduced the work load in general and the biomechanical constraints in particular.
Malchaire, J. B., & Rezk-Kallah, B. (1991). Evaluation of the physical work load of bricklayers in the steel industry. Scandinavian Journal of Work, Environment and Health, 17(2), 110–116. https://doi.org/10.5271/sjweh.1729