The average employee in Wales works an extra 6.2 hours per week - adding up to an extra £735m-worth of value to the Welsh economy.
"That's a huge amount of hours," said Rhianydd Wiliams from Wales TUC.
"We're asking employers to recognise these extra hours and maybe looking at better ways of managing time within the office so that people feel they can leave on time or have a proper lunch break."
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Mosques across Wales and the rest of the UK have opened their doors today to encourage people to find out more about the Islamic faith.
Rain quickly clearing this evening with blustery, locally heavy, showers following, merging at times into longer spells of rain.
After a chilly start it will be a blustery day with some decent sunny spells for most and isolated, locally heavy, showers.