Every day, 21.18 million people in the UK work nine to five. This may seem intuitive – we all know people tend to work best during daylight hours. But even within these parameters, individuals have very different sleep-wake patterns.

Our internal body clock is a natural process governed by circadian rhythms that regulate levels of energy and alertness throughout the day. So when we experience jetlag, or a lack of sleep, this interferes with our ability to think.

Much research has been done on when we work best, but little of that knowledge has filtered through to the workplace. The average employee will take a few hours after arriving at work to reach peak alertness at around noon. This peak then subsides until around 3pm. After this low, alertness tends to increase again until a second peak at 6pm. Then it’s a steady decline until the ultimate low at 3.30am. Finally, alertness climbs again and the cycle repeats.

This, however, is the average cycle with people deviating hugely. Some fall into early morning achievers (larks), while others work better in the evening (owls).

Consider the typical working day: a 7.30am start; a stressful commute to reach a fixed point before 9am; an hour for lunch often spent at the desk; and a tiring commute home leaving work at 5pm each day.

The notion of the nine-to-five working day was established in Victorian times, not an age much aware of worker welfare, and it is easy to see the conflict between this fixed structure and our natural circadian rhythms.

So how can businesses adapt? Already numerous companies are rejecting this outdated idea of a fixed working routine and embracing flexible working.

This change is as much down to changing mindsets as with re-organising business locations. Today’s managers are learning to measure on results rather than presenteeism. Many no longer regard workplace flexibility as a perk – it is expected. Given these changing values, business leaders are quickly learning how to get the most from employees, even if they do not see them on a day-to-day basis.

With the early evening peak of alertness occurring precisely when a vast majority of workers are wrestling with motorways or public transport on their commute home, what if that commute were simply eliminated? It’s won’t work for everyone, but there are a large percentage of professionals travelling unnecessarily to a fixed location. How much more productive these individuals could be if they worked nearer to home, arrived at the workplace fresh, and did not have to worry about leaving exactly on time in the evening in order to get back?

Solutions are available today. Businesses of every size and in every sector are consuming flexible workspace and a new pattern is emerging which aims to fit the workplace around the worker, rather than vice versa.

Clearly, this change is being driven by much more than acknowledgement of the internal body clock. Business leaders are looking at empty desk space in centralised offices and understanding the wasted expense. They are listening to workers struggling with the daily cost and frustration of commuting. And they are embracing flexible working to attract the best employees.

What this flexible approach provides is a way to tailor working times to individuals’ body clocks, in a way that isn’t feasible under a fixed structure.

Whether employers are quite ready to allow individuals to nap during the day during low-energy spells is a moot point. But there is certainly receptiveness for improved workplace wellbeing and for trusting employees to maximise their output on their own terms.

Giving a little scientific thought to the process of productivity – and allowing owls and larks to beat their wings to a different rhythm – works best for everyone.

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