Humans are most productive when working for 8 hours a day, 5 days a week.
If you work more than that you actually getting less done, not only you could spend the extra time with your family or doing something fun – you actually get less work done by working more.
Since the beginning of the industrial revolution researchers have been studying worker’s productivity, a lot of this research went into finding the optimal length for the work day, studies were done all over the world and for different industries from factory work to information technology and they all came up with the same result – 8 hours a day, 5 days a week, a total of 40 hours a week.
The reason we can’t get more done by simply spending more time working is that our productivity changes during the course of the day, when we start working in the morning it takes us a little while to get up to speed, We have a few hours where we are most productive and then we start to get a little tired.
As we become more tired our productivity drops, we get less done and we do more mistakes until we arrive at a point we’re starting to make mistakes faster then we can fix them – at that point the more we work the farther behind we get.
And that’s only the first part of the problem – after finishing a long day we get to work the next day and we are still a little bit tired, so our peak productivity that day is a little less than the previous day, and a little less then that the next day.
You can work long days if you have a close deadline, but that is not sustainable.
Research has shown that a team working 8 hours days and a team working 12 hours day will complete the same amount of work in 6 weeks – that means that in 6 weeks the productivity loss from being tired completely wiped out the gain from working more hours.
And after those 6 weeks the tem working 40 hours a week can continue working at the same productivity level indefinitely while the team working 60 hours a week or more is burned out and can hardly do any work at all.
Here is a more comprehensive article on the subject with graphs, formulas and references.
posted @ Wednesday, April 16, 2008 4:05 PM