12.3 TYPES OF INDUSTRIAL FATIGUE
Fatigue can be both physiological and psychological.
●Physiological fatigue is the inability to continue functioning at the level of one’s normal abilities. A person with physiological fatigue cannot lift as heavy a box or walk as far as he could if not fatigued.
Muscular fatigue resulting from prolonged physical work, are the example.
● Psychological, on the other hand, rather manifests in sleepiness or slowness. A person with psychological fatigue may fall asleep, may react very slowly, or may be inattentive. With micro sleeps, the person may be unaware that he was asleep. Sensory (degradation of sensory perception) and cognitive fatigue, or alertness, intellectual
fatigue are the examples of psychological fatigue.
Fatigue also differentiated by acute and cumulative fatigue
● Acute fatigue is experienced perhaps at the end of a long day, and
● Fatigue where you may still feel tired even after a night’s sleep this comes under cumulative fatigue. 'Acute fatigue’ has been recently explored by Jansen, Kant and van den Brandt (2002). They looked at the relationship between the need for recovery from work, prolonged fatigue and psychological distress in a large sample ( N = 12,095) from the Netherlands. They conceptualized need for recovery as the “ need to recuperate from work-induced fatigue, primarily experienced after a day of work'. They found that the need for recovery was a separate concept from prolonged fatigue.
Konz (1998a) recognizes that fatigue is likely to be related to long daily work hours especially if there is a lack of sleep; whereas occasionally, it will be due to long weekly work hours (cumulative fatigue). Many of the studies that we consider in this review use weekly working hours as their measure of ‘long hours’ and not daily hours. This means that cumulative fatigue may well be being measured as opposed to acute fatigue.