A biomechanical interpretation of the psychophysical determination of work capacity.
Advances in industrial ergonomics and safety II. Das B, Mital A, eds., Philadelphia PA: Taylor and Francis, 1990 Jan; 2:469-476
This U.S. Bureau of Mines study compares major trunk muscle activity during lifting tasks at weight levels below, at, and above the maximum acceptable weight of lift. The increase in peak and average muscle activity for the latissimus dorsi muscle pairs, and in average activity for the erector spinae muscle pairs, is greater from the medium- to the high-weight condition than from the low- to medium-weight condition (p<=0.05). This study shows that the increase in muscle activity, relative to external load increases, is nonlinear, and there are critical thresholds at which the worker judges the task to be unacceptable based upon biomechanical factors.
Muscle-function; Muscle-tension; Muscles; Musculoskeletal-system; Musculoskeletal-system-disorders; Muscular-disorders; Repetitive-work; Biomechanics; Back-injuries; Work-capacity
Advances in industrial ergonomics and safety II. Proceedings of the Annual International Industrial Ergonomics and Safety Conference held in Montreal, Quebec, Canada, 10-13 June 1990. The Official Conference of the International Foundation for Industrial Ergonomics and Safety Research