Harnessing the four-day week
Millie Green sits down with Dr Charlotte Rae to discuss the findings of her research into the modern phenomenon of the four-day week, its impact on our wellbeing, productivity and performance, and how these can have a commerical impact on our business.
The four day working week is a modern business phenomenon. More organisations and individuals are beginning to adopt this approach, backed by findings from national studies. Now, Dr Charlotte Rae at Sussex University is conducting a trial to further explore this field.
Millie Green at MDHUB finds out more.
Dr Charlotte Rae
Dr Charlotte Rae is an academic psychologist. After reading Andrew Barnes’ book The Four Day Week, in which Barnes charts his experience trialling a reduced working week in his business, Charlotte was curious to find out more. Despite less cumulative hours worked, productivity increased, which seemed counterintuitive at first glance. Team wellbeing also improved. Charlotte explained “I instantly thought: it’s because of whatever is going on in the brain.”
When Charlotte first developed the study, she worked with Sussex Innovation Centre, a business incubator. Sussex University had introduced her to the group as her proposed study had a “clear commercial impact.” It was here she met Helen Bailey, one of MDHUB’s facilitators. Helen signed up for the study and encouraged MDHUB Directors Fiona Shafer and Phil Green to take part, too.
While previous studies focussed almost exclusively on performance, Charlotte was keen to put wellbeing at the core of her research. Key to this approach is providing “focus group sessions” to help participants increase their efficiency. Charlotte said “it’s quite rare in our working lives that we take a moment to step back and reflect, because we are so bogged down in the day-to-day.” Charlotte and her team provide tips like reducing digital distractions and introducing new planning techniques to help participants get the most out of their reduced working hours. Phil explained that these tips have stopped him “jumping straight into email first thing rather than clearing anything I hadn’t finished the previous day.”
Participants in the trial have reported a consistent reduction in burnout and better quality sleep across the twelve week period. At the same time, engagement with work, and goal attainment both rose by a significant margin. They also found they were better able to switch off at the end of the day, rather than ruminating on work well into their evenings.
There are a number of possible reasons for these changes. One is that people are likely to be engaging in hobbies, spending time with friends and taking exercise classes on their free fifth day. “Hobbies are what’s known as recovery activities, where you’re doing something gentle and relaxing that’s different from your work.” Recovery activities are key to reducing cortisol in the body, which is “strongly linked to sleep. If you’re stressed and you have high cortisol, there isn’t a natural wave through the day”. This leads to a peak in cortisol in the middle of the night, waking you up prematurely. With less stress, increased time to decompress and lower cortisol levels as a result, participants have reported improved sleep and better engagement at work as a result.
Charlotte’s study is also collecting data about brain activity by inviting participants to an MRI scan at the start and end of their 12 week trial period. While more analysis is needed, Charlotte shared that “we’ve got some early hints that there is a brain signature for the four day week.” Participants have displayed increased activity in the default mode network. This is the part of the brain used when we “go into autopilot” for day-to-day tasks. This is associated with higher creativity and problem solving ability: “all the thinking has been going on unconsciously at the back of your mind. What the Default Mode Network does is creates the literal brain space to access free thinking.”
This has certainly been the case for Fiona, for whom working reduced hours has been a long process: “I loosely trialled the principle of a reduced working week in 2024 and managed to get my six day working week down to five.
In 2025, having committed fully to four day week project, I wouldn’t want to return to a full working week. I have worked hard at reprioritising my time and as a result, I am more engaged creatively and have more headspace. Some weeks it doesn’t always work but that’s fine, as that comes with running a business where no day is the same but the principle remains firmly in place.”
If you’re curious about the four day week, you can get free support by joining Charlotte’s trial, which is open through into 2026. Her team are looking for participants interested in introducing a reduced working week. Those who would like to reduce their hours but aren’t yet ready can also apply to join the control group.
Helen explained that through the study, “I’ve learned a lot about my relationship with work, some of it healthy, some of it not.” The study has been the push she needed to break a thirty-year habit of overworking, and commit to a four-day week. “It’s an incredible opportunity to get involved with the expertise at the university.” The study forces you to break societal norms, which can be very uncomfortable. Charlotte is an expert in navigating that discomfort, so take advantage of the support while it is available!”
Find out more about the trial and sign up to participate on the Sussex 4 Day Week trial website.
