Irish linked study reveals why working a four-day week is good for your health

Irish Independent

21-07-2025

That's according to a study of workers in the USA, UK, Australia, New Zealand, Canada and Ireland reported in Nature Human Behaviour.
Up to now, research conducted into the benefits of four-day weeks had been mostly done on a single case basis, rather than across sectors or countries.
The researchers involved were based in Boston College, the University of Cambridge and included Orla Kelly, Professor in Social Policy at UCD.
Prof Kelly's research shows, she said that most organisations that have implement a four day week on a trial basis, continue after the trial ends.
'Organisations' choice to keep this new working model supports employees' subjective assessment of productivity gains,' said Prof Kelly
'Irish companies were actually among the first cohort to participate in the trials, said Wen Fan, Associate Professor of Sociology at Boston College, who was first author on the paper.
'In February 2022, 12 companies out of the 16 companies in the very first cohort were from Ireland and trials were supported by Forsa trade union.'
'In terms of industry composition, the largest group comes from the administrative, IT and telecom sectors.'
In the study, workers said their job satisfaction and work performance had increased and fatigue and sleep problems decreased with a four-day week.
The findings highlight the potential for organisations to improve the well-being of employees by reducing workplace hours, said the researchers.
Trial results The scientists ran six month trials involving 2,896 employees in 141 organisations across seven English speaking countries, including Ireland.
They compared work and health related indicators - such as burnout, job satisfaction, and mental health– before and after the intervention.
The researchers also compared these results with the data generated from 285 employees at 12 companies that did not introduce a four-day week.
Employees who had eight or more hours shaved off their working week, reported larger reductions in burnout and improvements in mental health compared to workers at companies who kept a five-day working week.
There were similar, but smaller, effects seen for workers that had 1-4 or 5-7 hour reductions in their working week.
The benefits, the researchers state, can be at least partially explained by less sleeping problems and fatigue, and improved individual work ability.
Stress, burnout, fatigue and work-family conflict declined, as did the numbers experiencing sleep deprivation.
Employees used the day off for hobbies, household work, grooming and increased the time they spent exercising.
'We have large well-being improvements over a range of metrics,' said Professor Wen.
'We find that the bigger the worktime reduction in hours, the bigger the well-being increase,' said Prof Wen.
The researchers are calling for more future, randomised studies on worktime reductions, and possibly government sponsored trials.
'One of the most pressing questions is how worktime reduction can be scaled to non-office-based jobs where productivity gains are less tangible,' said Prof Kelly.
'A good first step would be for the government to provide support for a trial among these sectors to better understand how this opportunity to work less for the same pay can be universalised,' she added.