[…]

However, when the week went over 25 hours, overall performance for the test subjects decreased as “fatigue and stress” took effect.

The report, which was published in the Melbourne Institute Worker Paper Series, invited 3,000 men and 3,500 women in Australia to complete a series of cognitive tests while their work habits were analysed.

It was found those working 25 hours a week performed best while those working 55 hours a week showed results worse than retired or unemployed participants.

[…]

https://tech.co/study-work-three-days-week-2016-04

https://www.independent.co.uk/news/uk/home-news/workers-over-40-perform-best-with-three-day-week-25-hours-melbourne-institute-study-a6988921.html

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