A ShackBurger, cheese fries, and milkshake are arranged for a photograph at a Shake Shack Inc. restaurant in Lexington, Kentucky, U.S., on Wednesday, March 6, 2019. Shake Shack is still failing to bring in more diners as it expands outside its home market of New York in the fiercely competitive restaurant space -- the chain plans to open 36 to 40 company-owned U.S. locations in fiscal 2019. Photographer: Luke Sharrett/Bloomberg via Getty Images
Luke Sharrett/Bloomberg/Getty Images
A ShackBurger, cheese fries, and milkshake are arranged for a photograph at a Shake Shack Inc. restaurant in Lexington, Kentucky, U.S., on Wednesday, March 6, 2019. Shake Shack is still failing to bring in more diners as it expands outside its home market of New York in the fiercely competitive restaurant space -- the chain plans to open 36 to 40 company-owned U.S. locations in fiscal 2019. Photographer: Luke Sharrett/Bloomberg via Getty Images
Now playing
02:34
Why Shake Shack is testing out a 4-day work week
Now playing
03:21
Teachers under pandemic stress are quitting: I didn't feel safe
Now playing
03:01
A return to the office brings 'some anxieties, some anticipation'
Now playing
03:08
'I want women to be as rich as humanly possible': Meet TikTok's wealth coaches
Now playing
03:38
Stimulus package aims to get mothers back to work
Now playing
02:42
A challenging year for women: Millions are out of work
Branislav Nenin/Shutterstock
Now playing
02:27
Is working from home the new normal?
Shutterstock
Now playing
04:47
Permanent work from home is here. Will cities survive?
Now playing
03:09
Trivago CEO's son crashes live CNN interview
Now playing
02:43
What some companies are doing to establish WFH balance
Now playing
02:58
Childcare challenges force some working moms to put their careers on hold
CAMIO
Now playing
03:15
This AI technology tracks employees to enforce social distancing
BBC/Sky News
Now playing
01:14
Watch children interrupt live BBC, Sky News interviews
future office coronavirus covid 19 pandemic technology social distancing sebastian pkg intl ldn vpx_00004211.jpg
future office coronavirus covid 19 pandemic technology social distancing sebastian pkg intl ldn vpx_00004211.jpg
Now playing
02:42
Acrylic glass, masks, warning signs: Is this the office of the future?
Now playing
01:51
Five tips to look more professional on a video conference
Now playing
04:27
Working from home could shake up parenting dynamics
(CNN Business) —  

A growing number of smaller companies are adopting a four-day workweek. Now the results of a recent trial at Microsoft (MSFT) suggest it could work even for the biggest businesses.

The company introduced a program this summer in Japan called the “Work Life Choice Challenge,” which shut down its offices every Friday in August and gave all employees an extra day off each week.

The results were promising: While the amount of time spent at work was cut dramatically, productivity — measured by sales per employee — went up by almost 40% compared to the same period the previous year, the company said in a statement last week.

In addition to reducing working hours, managers urged staff to cut down on the time they spent in meetings and responding to emails.

They suggested that meetings should last no longer than 30 minutes. Employees were also encouraged to cut down on meetings altogether by using an online messaging app (Microsoft’s, of course).

The effects were widespread. More than 90% of Microsoft’s 2,280 employees in Japan later said they were impacted by the new measures, according to the company.

By shutting down earlier each week, the company was also able to save on other resources, such as electricity.

The initiative is timely. Japan has long grappled with a grim — and in some cases, fatal — culture of overwork. The problem is so severe, the country has even coined a term for it: karoshi means death by overwork from stress-induced illnesses or severe depression.

The issue attracted international attention in 2015, when an employee at Japanese advertising giant Dentsu died by suicide on Christmas Day. Tokyo officials later said that the staffer had worked excessive amounts of overtime.

Two years later, a reporter at a Japanese broadcaster died after working punishing long hours. Her employer said she had clocked in 159 hours of overtime the month before her death.

That has led businesses to start searching for solutions. Some companies have begun offering employees more flexibility, and the government has launched a campaign called “Premium Friday,” which encourages workers to leave early every last Friday of the month.

Microsoft, for its part, says it will conduct another experiment in Japan later this year. It plans to ask employees to come up with new measures to improve work-life balance and efficiency, and will also ask other companies to join the initiative.