Elon Musk, CEO of Tesla and SpaceX, has made no secret of the fact that he regularly works a 100-hour week. And GE CEO Jeffrey Immelt spent 24 years putting in 100-hour weeks.

Yet this bragging about working long hours is doing us no good at all.

While these executives put their long hours down to where they are today, research consistently shows that working too much is bad for us.

Long hours have a toll on employees’ health, and affect staff turnover, absenteeism and productivity.

How long hours affect health

Working a 55-hour week brings with it a risk of coronary heart disease and stroke, says a recent research article published in The Lancet. Working long hours can also make you fatter, increase your risk of diabetes and make you depressed.

It can even lead to an early death. A study looking at the health of people who sat for a long time found that they had a nearly 50% increased risk of death from any cause.


Have you read?
Why one company is paying its staff to sleep

The research is clear: sitting at a desk for long periods of time is detrimental, and not only in terms of health. It doesn’t necessarily lead to higher productivity either. A study carried out by Cambridge University and Rand Europe suggests that sleeping for fewer than six hours per night can significantly affect productivity.

Another study found that productivity actually drops dramatically with long hours. In one case, those who toiled away for an extra 14 hours produced nothing more in that time.

Those that adhere to a long-hours office culture often turn up at work when they are sick, so-called “presenteeism”, but their performance suffers. In a recent article in the Financial Times, Sir Cary Cooper, president of the Chartered Institute of Personnel and Development, the UK-based professional body for HR, said: “One of our problems is that even [among] the people who turn up to work, a big proportion of them are not delivering.”

​A changing culture

Thankfully, some employers are leading the way in terms of changing the long-hours culture.

Companies like Aetna, a US-based insurance group, which has introduced a sleep scheme to encourage employees to get their seven hours of shuteye each night.

For every 20 nights an employee sleeps seven hours or more, Aetna rewards them with US$25. The company uses various methods to track employees’ sleep, including self-recording and the use of Fitbit fitness trackers.

Aetna brought in Duke University to study the effectiveness of its wellness program, which also includes better sleep information, yoga, and meditation. CEO Mark Bertolini said he's seen "69 minutes more a month of [worker] productivity on the part of us just investing in wellness and mindfulness."

 The link between effective leadership and a good night's sleep
Image: McKinsey

Another US company, The Boston Consulting Group, has brought in a new way of working called PTO – Predictability, Teaming, Open Communication.

Calling it “A Better Way to Work”, PTO builds in collectively agreed time off for each team member, and a transparent workload that means that “low-value work doesn’t consume high-value personal and professional time.”

The results for the company have been impressive. The group has reported “exceptional improvements in both personal satisfaction and project performance after adopting PTO, including an average 35% increase in teamwork and collaboration, a 35% increase in value delivered to clients and a 100% increase in effectiveness.”

Put another way, working long hours may well be a complete waste of time.