The eight-hour workday is not based on the optimal number of hours a human can concentrate. In fact, it has almost nothing to do with the kind of work most people do now: Its origins lie in the Industrial Revolution, not the Information Age.

In the late 18th century, 10-16 hour workdays were normal because factories "needed" to be run 24/7. When it became clear that such long days were both brutal and unsustainable, leaders like Welsh activist Robert Owen advocated for shorter workdays. In 1817, his slogan became: "Eight hours labour, eight hours recreation, eight hours rest."

However, this eight-hour movement didn't become standard until nearly a century later, when, in 1914, Ford Motor Company astonished everyone by cutting daily hours down to eight while simultaneously doubling wages. The result? Increased productivity.

Thus, while it may be hard for some to believe, the eight-hour workday was initially instituted as way of making the average workday more humane.

Now, the workday is ripe for another disruption. Research suggests that in an eight-hour day, the average worker is only productive for two hours and 53 minutes.

That's right--you're probably only productive for around three hours a day.

According to the Bureau of Labor Statistics, the average American works 8.8 hours every day. Yet a study of nearly 2,000 full-time office workers revealed that most people aren't working for most of the time they're at work.

The most popular unproductive activities listed were:

Reading news websites--1 hour, 5 minutes Checking social media--44 minutes Discussing non-work-related things with co-workers-- 40 minutes Searching for new jobs--26 minutes Taking smoke breaks--23 minutes Making calls to partners or friends--18 minutes Making hot drinks--17 minutes Texting or instant messaging--14 minutes Eating snacks--8 minutes Making food in office--7 minutes

This is particularly good news for freelancers and others who work from home. It's easy to feel like you're not "doing" enough when you don't have to go into an office. Yet this research suggests that if you're productive for just three hours a day, you're outputting the same amount as someone in the office for eight hours.

And imagine if we truly embraced this information. Even if we didn't cut a workday down to three hours, what if we cut it to six? What if the norm was a workday of 11 a.m.-5 p.m.?

People would be better rested, more focused, and likely more productive.