The Relationship of Physiological Parameters and Subjective Strain in Manual Material Handling (MMH) Task

The most common types of injuries associated with manual handling are strains, sprains, fractures, lower back pain from awkward postures, muscle fatigue, and musculoskeletal issues affecting the back, neck, shoulders, elbows, and hands. Therefore, the fundamental approaches for evaluating the manual material handling are physiological, psychophysical, and biomechanical, with physiological and psychophysical approaches being the most common. Whereas the psychophysical approach concerned with analyzing the subjective strain of the worker's experience during lifting tasks that depends on individual fitness. Thus, in the present paper, it was tried to explore the interrelationships among physiological parameters (heart rate, energy expenditure) and subjective strain felt by manual handlers when lifting heavy loads.