Researchers said the results of the trial conducted with employees of a learning technology firm provide ‘further compelling evidence’ on the benefits of four-day work weeks for employees
Learning technology firm Thrive has taken part in the UK’s first medical trial of the four-day work week, which found that shorter hours lead to happier, more productive staff.
Conducted by Thrive in partnership with the University of Sussex, the trial collected data on 115 Thrive employees between July and October 2024, including research tests such as MRI scans, blood tests and sleep tracking, as well as weekly questionnaires covering their workplace experiences and wellbeing.
Regular feedback was also sought from Thrive customers – which the company supplies with an artificial intelligence (AI)-powered learning management system (LMS) to help them train and upskill their employees faster – to determine the impact of the trial on quality of service, while sales and product metrics were also evaluated to assess the effects on business productivity.
According to the results, there were notable improvements in a number of employee wellbeing metrics – particularly those related to stress levels, sleep quality, and detachment from work – indicating a significant improvement in work-life balance.
This includes a 20% reduction in sleep problems, a “considerable” 8.6% reduction in perceived stress, a 14.7% decrease in “emotional exhaustion”, and a “statistically significant” 5% reduction in anxiety symptoms.
“The results speak for themselves. These significant improvements in areas related to physical and mental wellbeing demonstrate the transformative power of a four-day work week,” said Charlotte Rae, research lead at the University of Sussex. “Improved sleep quality and reduced stress and exhaustion are factors that could have a significant impact on our health, with the potential to enhance our lives in and outside of work. This study provides further compelling evidence for the benefits of flexible working models.”
In terms of the impact on work productivity, the trial found that despite working fewer hours, the task execution of employees remained consistent, with many reporting increased goal attainment and self-efficacy. Researchers said this reflected a boost in their confidence and belief in their ability to achieve desired outcomes at work.
Cassie Gasson, co-CEO at Thrive, said that being a tech-focused business brought a range of advantages to the firm when conducting the trial: “Working in the tech space means our teams are naturally aligned with using tools like AI, which allowed us to streamline workflows and prioritise the work that matters most.
“As creators and users of AI-powered solutions, we’ve seen first-hand how impactful it can be in enabling flexibility without compromising on results, which has proven beneficial in the context of the four-day work week.”
She added that while Thrive’s teams are already equipped with the skills and tech to make the most of a four-day week – as the company has used its platform to continually upskill its own workforce – the trial highlighted that success depends on fostering the right culture to make the working changes sustainable.
“Because of this, we recognise that this approach doesn’t suit every business or team dynamic,” she said. “By balancing flexibility with customer needs, we’re exploring how to make the four-day work week a sustainable option for the future, opting for a seasonal approach going forward.”
Widespread cultural change needed for success
Despite the dual benefits on employee wellbeing and productivity, the trail highlighted the difficulty of providing consistent customer service in a business landscape where most other firms are still operating on the traditional five-day working model.
“Our four-day work week trial revealed incredibly encouraging results and we saw a fantastic impact on the people within our business,” said Gasson. “While we would have loved to implement it on a full-time basis, our experiences in the trial highlighted that the success of a four-day work week will rely on widespread cultural change across the UK business landscape.
“As a business serving hundreds of organisations, it highlighted that five-day coverage for our customers is essential when they’re operating more traditional ways of working.”
Gasson added that the UK government should consider implementing policies to help make a four-day work week a reality: “The benefits are evident through its potential to boost business productivity, increase wellbeing, and generally make the country happier and healthier. The UK has the potential to take the lead on this by pioneering the four-day work week and reaping the rewards.”
Until then, she said Thrive would look to implement a four-day work week on a seasonal basis.
In May 2022, more than 3,000 workers at 60 companies took part in a coordinated, six-month trial of a four-day working week in the UK. Organised by 4-Day Week Global in partnership with think tank Autonomy and the 4-Day Week UK Campaign, the trial saw 60 firms – including several technology companies – adopt a reduced working week with no loss of pay from June to December 2022.
Speaking with Computer Weekly at the time, many of the tech firms highlighted positive results in terms of productivity, as well as talent attraction and retention.
While issues were highlighted for business in sectors such as cyber security, where “switching off” for a day is not necessarily an option, researchers at Autonomy said businesses could circumvent this issue through the introduction of a better rota system or by hiring additional staff. Ultimately, most firms involved deciding to continue with shorter weeks on a permanent basis.
Prior to this, the largest four-day week trial to date was run in Iceland by Reykjavík City Council and the national government, which included more than 2,500 workers. It found that productivity either remained the same or improved in the majority of workplaces involved.
In November 2023, Autonomy published a paper on the potential for AI-driven large language models (LLMs) to shorten people’s work weeks, noting while they could lead to significant reductions in working time without a loss of pay or productivity, realising the benefits of such AI-driven productivity gains in this way will require concerted political action.
Autonomy noted that although people have long been predicting and expecting far shorter working weeks due to technological advances, historical increases in productivity over recent decades have not translated into increased wealth or leisure time for most people, largely as a result of economic inequality.
It said that there is often a sense of pessimism around AI-driven productivity gains, with most conversations emphasising the potential for job losses and degraded working conditions, but that such gains could also be used to deliver shorter working weeks for many while maintaining their pay and performance.
A number of IT firms have moved to a four-day week over the past couple of years due to the benefits, including cloud provider Civo, channel player Highgate IT Solutions, and challenger bank Atom.
