It might feel like we’ve been locked in the nine-to-five structure since the dawn of time, but the eight-hour day was once a revolutionary concept. First championed by socialist Robert Owen in 1817, who believed workers deserved eight hours each of work, recreation and rest, by the 20th century it was proved productivity increased the fewer hours we worked.

Now we have electricity, we can effectively work any time we want. But all-night working isn’t going to catch on (humans sleep when it’s dark because our bodies produce more melatonin – a hormone which causes drowsiness), but perhaps we should be able to tailor work hours to our personal needs?

“The hours you are most productive are driven by your circadian (biological) rhythm, which determines whether you’re a morning or a night person, a lark or an owl,” explains Monica Parker, behaviourist and head of workplace consultancy at Morgan Lovell. “Larks have shorter circadian rhythms, meaning they sleep through their peak hour of sleepiness, and wake up at 7am refreshed. Owls, with longer rhythms, usually wake up around their peak hour of sleepiness at 7am, so still have high levels of melatonin, making them groggy,” she explains.

Some secondary schools are trying to combat this natural drowsiness by proposing lessons start at 11am. If workers too can control their own timetable, lie-ins might no longer warrant a P45. “The most productive period is the beginning of the day,” reveals Erin Falconer of pickthebrain.com – the exact time depends on your body clock. “People are capable of creative tasks like writing and solving complex technical problems.”

But after a couple of hours of intense work, energy levels drop and towards lunch, workers are achieving practically nothing. In fact, Falconer believes only three to four hours a day could be classed as highly productive. She believes the answer lies in four hours of screen time, interspersed with other, physical activities. “The traditional office setting doesn’t accommodate this because there are few ‘recharge activities’, which can be as simple as household chores or running errands,” explains Falconer.

Working from home means that when we lose energy we can do something else – cook, walk the dog or even sleep – until the energy returns. “People need to build in 25 minutes a day of uninterrupted thinking, away from technology and the expectation of immediate response,” says Parker. “Companies are creating tech-free zones while Nike and Google have nap rooms. Studies show that 20 minutes of sleep in the afternoon provides more rest than 20 minutes extra in bed in the morning. It’s when our bodies naturally slow down and need a top up.”

The new model could work for our bosses too. “Employers don’t pay for unproductive time and employees get to work in a pattern that adjusts to their personal lives,” says Falconer. Just imagine, two hours’ work in the morning, an hour off then maybe two more shorter stints. You’d pay your bills on time, get your groceries in the daylight and be super productive at work. It might even make that gym membership worthwhile, too.

Lunch Breaks

How to make your workplace more efficient