Subjective Burden and Task Performance during Simulated Long Working Hours

Abstract

Long working hours are associated with increases in cardiovascular diseases and are also important factors for karoshi. We have confirmed that cardiovascular burden increases due to long working hours in laboratory, and older workers (over 50s) suffer more cardiovascular burden than younger workers. Aging is not only a risk factor for cardiovascular diseases, but it can also be a factor that affects work efficiency. This paper reports the results of subjective burden and task performance of workers in their 30s to 60s. We examined the subjective fatigue, stress and sleepiness and task performance during long working hours in lab. The experiment conducted from 9:00 to 22:00 and was divided into four task sessions. In each session, three tasks (color-word task, mental arithmetic task and number copy task) were performed once for 45-minutes in random order. As results, subjective stress and fatigue increased and task performance was significantly higher in the late afternoon and evening. No differences among age groups were detected. In conclusion, although task performance has not declined, attention is required if long working hours are unavoidable due to increased mental and physical burden.