Working longer hours can have a negative impact on productivity, according to new research conducted by John Pencavel of Stanford University.

Research published previously by John Hicks, a British economist, found the more workers slaved away, the more energy they would lose and the less productive they would become. Working shorter hours resulted in higher output of productivity and a far more efficient workforce.

To take this concept one step further, Mr Pencavel examined research undertaken by the British Health of Munition Workers Committee (HMWC) during the first world war. During this period there was a shortage of weapons and ammunition, resulting in a desperate need for heightened productivity amongst those working in the ammunitions factories. HMWC had to provide the government with advice regarding the health and efficiency of workers in the ammunitions factories and undertook extensive tests, most of which were on women, who dominated the munitions industry.

The study looked at the link between hours worked and performance and found that workers needed shorter hours in order to maximise performance.

After 50 hours of work per week, output started to fall – productivity at 70 hours a week differed little from at 56 hours of work, which meant the extra 14 hours was a waste of time and money for the organisation. The study also found that the absence of a rest day significantly damaged hourly output.

There have been several studies on the link between working too much and decreased productivity, and earlier in the year we published a piece that explores how workaholism can actually damage your career due to issues with health, addiction and depression.

This research therefore serves to highlight what we have long suspected – overworking not only hinders fun and frivolity but can actually make you worse at your job.

Image by Patrick Gensel