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Appropriate visual display terminal (VDT) location is a subject of ongoing debate. Generally, visual strain is associated with higher placement, and musculoskeletal strain is associated with lower placement. Seeking resolution of the debate, this paper provides a comparison of results from previous lab-based monitor placement studies to recommendations and(More)
Prolonged use of video display terminals (VDTs) has been shown to be a risk factor for musculoskeletal and visual discomfort. A standard workplace design recommendation is to position the centre of the VDT 15 degrees below horizontal eye level. Recently a viewing angle of 40 degrees below horizontal has been suggested based on studies that have indicated(More)
Biomechanical models of the spine have traditionally assumed that workplace lifting conditions (weight, posture, motion, etc.) precisely dictate the magnitude of individual muscle forces necessary to maintain a biomechanical balance within the trunk. However, because there are a large number of muscle groups within the trunk there is also an infinite number(More)
Electromyography (EMG) and normalized EMG have been accepted as methods of quantifying the activity level of a muscle. Normalized EMG, in conjunction with the EMG/force relationship and muscle cross-sectional area data, allows researchers to estimate the amount of muscle force exerted across a joint. An accurate description of this muscle force is a(More)
The effect of warning time (preview) and task symmetry on the trunk muscular response to sudden loading conditions was investigated. Eleven subjects were asked to catch falling weights with four levels of preview (0, 100, 200, and 400 ms) in saggitally symmetric posture and asymmetric posture. For each of the eight muscles sampled with surface electrodes,(More)
An experiment was performed to determine the reaction of the trunk muscles, using electromyography, and intra-abdominal pressure to components of trunk loading commonly seen in the workplace during manual materials handling. These components included angular trunk velocity, trunk position in three-dimensional space and trunk torque exertion level. The(More)
People working in an office environment often have to deal with significant cognitive workload due to the coordination of multiple, simultaneous tasks. The objective of this research was to examine the impact of cognitive load in office-type tasks on physical-stress response, using a dual-task paradigm involving a primary cognitive task and secondary typing(More)
STUDY DESIGN An electromyography-assisted biomechanical model was developed using electromyographic (surface and in-dwelling) data collected during asymmetric lifting and twisting activities. OBJECTIVES To develop a biomechanical model of the lumbar region that considers the ability of the broad, flat muscles of the trunk (external obliques, internal(More)
A limited number of studies have focused on computer-use-related MSDs in college students, though risk factor exposure may be similar to that of workers who use computers. This study examined computer use patterns of college students, and made comparisons to a group of previously studied computer-using professionals. 234 students completed a web-based(More)
Repetitive, high-force pinch grip exertions are common in many occupational activities. The goal of the current study was to quantify the relationship between lateral pinch grip span (distance between thumb and index finger) and lateral pinch grip strength. An experiment was conducted in which 40 participants performed maximal lateral pinch grip exertions(More)