An Australian study has found that people over the age of 40 perform at their best when they work three days per week and not longer.
Research published in the Melbourne Institute Worker Paper series indicated that cognitive functionality begins to decline after 25 hours' work per week for middle-aged people.
More than 6,000 men and women over the age of 40 participated in the study and it was found that those working 25 hours per week performed best, while those working 55 hours per week showed results worse than that of retired or unemployed participants.
"Work can be a double-edged sword, in that it can stimulate brain activity, but at the same time long working hours can cause fatigue and stress, which potentially damage cognitive functions," said one of the authors of the study, Professor Kolin McKenzie.
McKenzie believes the study indicates differences in working hours for maintaining cognitive functioning in middle-aged and elderly adults.
"This means that, in middle and older age, working part-time could be effective in maintaining cognitive ability," McKenzie said in the report.