Underground coal miners who work in low-seam mines frequently handle materials in kneeling or squatting postures. To assess quadriceps and hamstring muscle demands in these postures, nine participants performed lateral load transfers in kneeling and squatting postures, during which electromyographic (EMG) data were collected. EMG activity was obtained at five points throughout the transfer for ...

Numerous literature reviews indicate a moderate to strong association between manual material handling (MMH) and back injury. A few biomechanical studies contrasted the work techniques of female and male workers during MMH. Recently, Plamondon et al. (2014) found that one important biomechanical variable that characterized experienced females relative to male experts, during lifting of 15-kg bo...

America’s workforce is becoming more diverse. Generally, this diversity includes workers with different anthropometry (size, shape), capabilities, work experiences, and ethnicities. More importantly, the workforce is also aging and becoming heavier. However, the impact of aging and obesity is typically not considered in traditional ergonomic modeling. This paper explores the potential impact of...

OBJECTIVES Existing methods for practically evaluating musculoskeletal exposures such as posture and repetition in workplace settings have limitations. We aimed to automate the estimation of parameters in the revised United States National Institute for Occupational Safety and Health (NIOSH) lifting equation, a standard manual observational tool used to evaluate back injury risk related to lift...

The objectives of this study were to evaluate how lifting capacity and subjective preferences are affected by different lifting speeds. The maximum lifting capacity of lift was determined with three independent variables, lifting speed, lifting technique, and lifting height. Questionnaires were evaluated after the experiment by the participants for the lifting speed preferences. This study foun...

INTRODUCTION In spite of the widespread use of automation in industry, manual material handling (MMH) is still performed in many occupational settings. The emphasis on ergonomics in MMH tasks is due to the potential risks of workplace accidents and injuries. This study aimed to assess the effect of box size, frequency of lift, and height of lift on maximum acceptable weight of lift (MAWL) on th...

Purpose: Low back pain is one of the most common musculoskeletal disorders, and lifting is one of its risk factors. The activities of lumbar muscles as the main muscles involved in lifting are important with regard to identification of the allowable limits and the injury mechanisms as well as the motor control aspects. This study aimed to investigate the effects of the lifting speed on the lumb...