NIRS in ergonomics: Its application in industry for promotion of health and human performance at work

Demands of a job may include executing physical actions and/or performing cognitive judgments. The impact of these demands is dependent on the abilities of the individual performing the work. In order to ensure acceptable load levels for promotion of health and human performance at work during repetitive activities such as pushing, pulling, lifting, carrying, reaching and assembling, the physical capabilities of the workers have to be investigated. While the description of pulmonary oxygen consumption kinetics provides a valid and useful indication of cardiorespiratory function during changes in workload, it does not allow the measurement of changes in the oxygen content of the working muscle. Near-infrared Spectroscopy (NIRS) has been successfully employed to measure muscle and brain oxygenation during rest and exercise. Evaluation of central and peripheral responses during working tasks can predict the effectiveness of the workers' performance. This paper reviews the role of NIRS-derived measures in assessing human performance in the workplace by evaluating demands of executing physical actions and/or performing cognitive tasks in a controlled laboratory environment or in the field.Relevance to industryWorkers often have to exert repeated muscle contractions and make cognitive judgments while operating under a variety of physical constraints. NIRS-derived measurement allows the evaluation of workers with respect to muscular capacities, physical workload situations and the degree of mental effort required to perform the task.