How long should your workweek be? One way to look at it is “whatever my employer says it is”. But that’s a passive attitude. A second way is to look in terms of productivity. But productivity is hard to measure for knowledge workers, and is a company-centric perspective. So, in this blog post, I wanted to take a third perspective, and ask what’s good for physical and mental health — an individual-centric perspective. This perspective will keep your body and mind functioning well for decades to come.
We need to re-evaluate from first principles rather than accepting 9-5 as the default. Actually, 9-5 originated in the 1800s in factories, and knowledge work has blindly adopted it. Instead, we need to figure out what works better for knowledge work, which is creative and intellectual, unlike assembling cars in a factory.
With this context in mind in mind, let’s see what scientific studies have found regarding the minimum and maximum work hours:
Focused work for 4-5 hours a day
You can work only for 4-5 hours at a stretch with maximum focus and intensity. After that, you need to relax for a couple of hours, such as by taking a long walk in the woods1 or swimming. After you do, you may get an insight that you spend another hour noting down. That’s a total of 20-30 hours a week.
Longer hours than this work only for uncreative people like call center workers.
4-5 hours of focused work is the strategy that the highest achievers have used, like Ernest Hemingway, Beethoven, Einstein, and Charles Darwin when writing his book on evolution.
Unfortunately, Silicon Valley in particular, and the startup world in general, worships long hours. They believe that you can succeed only by working heroically, pushing yourself to breakdown or burnout. This misbelief comes from confusing hours (input) for productivity and creativity (output). Human beings are not like a machine that produces constant output: if you have a generator that generates 1 unit of electricity per hour, and you run it for 8 hours, you’ll get 8 units of electricity. People are not machines, so we shouldn’t assume linear productivity. Working less can produce the same results.
One company that tried 4-5 hours of focused work per day found that it leaves no room for team culture, loyalty and relationships. So add some time for that.
A 4-day workweek is healthier than 5
A study from the UK found that after switching to a 4-day workweek, 43% reported better mental health2. Let’s unpack the components of mental health:
39% of employees reported less stress3.
71% reported less burnout4.
54% reported less negative emotions. 64% reported more positive emotions.
Anxiety decreased.
Moving on from mental health to physical health, 37% reported better physical health5. Let’s unpack the components of physical health:
30% reported that they were less likely to feel too tired to cook8.
45% reported better relationships.
55% reported that they were able to do better work9.
52% reported they traveled more10.
48% reported they they were more satisfied with their job.
In summary, 32 hours is healthier than 4011. For me, the days of a full-time job, defined as 40 hours per week, are over.
What’s the minimum you should work?
Let’s revisit this topic, but from the other direction: what’s the minimum number of hours in a week you should work? Before we get to that, though, we need to recognise that unemployment results in a decline in physical and mental health and well-being not just of the unemployed person but also his family: distress, anxiety, unhappiness and dissatisfaction with life.
To avoid these, work at least 8 hours a week. If you’re already working 8 hours, working more doesn’t improve these outcomes.
So, if you’re taking a career break, instead of dialing work down to 0, think about whether it makes sense to dial it down to 8.
Conclusion
Choose any number between 8 and 32 and work that many hours per week.
Leave your smartphone at home. Listening to a podcast or an audiobook, or checking your inboxes, dilutes the benefit of the walk.
while 16% reported worse
while 13% reported more, and the remaining 48% reported no change.
while 22% reported more, and the remaining 7% reported no change.
while 18% reported worse.
while 14% reported more
while 15% reported worse sleep (such as insomnia), and the remaining 45% reported no change.
while 15% reported the opposite, and 15% reported no change.
while 19% reported worse, and the remaining 26% reported no change.
while 44% reported no change.
So True; it still amazes me that people have moved forward with so many things but still stick with an 1800 paradigm (9-5) that too from such a different industry;