Research has found that body temperature is slow to change, and seems to adjust after three weeks. Heart rate and blood pressure change more quickly. The internal disagreement between circadian rhythms can cause physiological problems.
In addition to this, it is harder for night shift workers to get the same amount and quality of sleep as day workers. This is due to the fact that there is much more noise during the day, making it even harder to sleep when one’s body is also telling them that they should be awake.
Also, social lives suffer. A person may not get to see as much of their family as they would like or get to socialise with their 'day working' friends. If they do socialise it may be when they should be sleeping - thus exacerbating the problem.
Shift workers usually change their shifts often and are moved backward (e.g. evening to day, day to night, and night to evening). Many shifts work on a weekly rota, so the body never has time to adjust itself.
According to Czeisler et al (1982), it would be more conducive to change shifts less often (every 21 days) and also to change forwards as opposed to backwards (e.g. day to evening, evening to night, night to day). Czeisler found that following these changes at a chemical plant in Utah, there were improvements in both work production and staff morale. However, in certain jobs, it just is not possible to make these changes, and the results can be poor memory and bad decision choices.
There are several disasters such as Three Mile Island and Chernobyl which occurred when important decisions had to be made between the hours of 1:30am and 4:30 am. This is when the body is at its least active and should be resting.
The increased accidents during the night shift may not be due to the tiredness of the worker, but may be due to poor lighting levels, or because there are just fewer staff than usual.
When deciding how to help the shift worker, several things need to be taken into account. Age affects the ability to cope with change, and people over 50 generally find adjustment the hardest. Someone with good physical fitness finds it easier to adjust than someone of poor fitness. In addition, being a morning person (someone who goes to bed early and wakes up early) is also a disadvantage. Research shows that females find shift work more difficult, possibly due to family responsibilities and partly because women need more sleep than men do.
There are problems with studying shift work, as employees worry that the questions are being asked for the benefit of their bosses whilst employers worry that their working practices are being questioned. They therefore act differently during these studies. In addition, many people find shift work difficult, and therefore do not stay very long, which makes research into bodily rhythms difficult as it entails studying changes over time.
Coping strategies can further help the shift worker. On a rapidly changing shift, the worker needs lots of bright sunshine in the day, and should avoid a heavy meal before the evening shift, as this increases sleep. It is also advisable to have a short nap at some time during the night - so that the body recognises that this is also sleep time for when the shift changes back.
