Here on, one of my most popular posts ever was entitled "Why Working More Than 40 Hours a Week Is Useless." It’s easy to see why. Complaints about long hours are incredibly common and just about every business owner has experienced the toll they can take on your psychology, body and family. The premise that you can get more done by shortening your workweek is bound to be very seductive.

But was that headline (and the decades of research on productivity that stood behind it) just wishful thinking?

A new study recently featured in the Harvard Business Review’s ‘Defend Your Research’  column suggests yes. If this subject fascinates you, it’s well worth a read in full, but the gist of the argument is that throughout the 1980s and mid-90s wages per hour over 40 hours a week declined, meaning the more you worked the less you made per hour. While starting in mid-90s overwork started to pay, with those working more than 40 hours a week earning more hourly with each additional hour they put in.

The Overwork Premium

Study co-author Cornell’s Kim Weeden sums it up: "By  the mid-1990s, overworkers received higher wages per hour compared to full-time workers with comparable levels of education, experience, and other attributes. By the end of the 2000s, overworkers earned about 6% more per hour than their full-time counterparts. This shift from wage penalty to wage premium implies that overworkers experienced a much sharper increase in their hourly wages than regular full time workers."

Which doesn’t necessarily mean that overworkers get more done. It could just be that bosses are increasingly expecting their teams to put in long days to signal commitment and garner higher pay. "In the new knowledge economy, particularly where work is organized in teams, productivity can be very hard to observe directly. In the absence of direct measures of productivity and contributions, employers may use the number of work hours as a signal,” notes co-author Youngjoo Cha of Indiana University.

So Should You Burn the Midnight Oil?

Which is another way to say that you should probably take these findings with a grain of salt. As your own boss, you have no one to show off to, so all that counts is how much you actually produce, not who you wow with your life-crushing dedication. As Business Insider recently reaffirmed, "decades of research supports the 40-hour workweek and shows that working longer can lead to serious negative effects on health, family life, and productivity," before going on to round up some of the greatest hits when it comes to investigations into the question.

But as a manager, you may benefit from this new study in other ways, namely as a reminder that it’s looking increasingly likely that social trends are pushing highly skilled workers towards longer hours. You may be being swayed by these same forces, so its worth examining your company to see whether you’re succumbing to the creeping forces of overwork and whether, truly, you want to be. If this research is a window into the collective soul of high achievers, it appears maybe we should all do some soul searching.

Check out the HBR post for more on how this trend may be impacting the gender wage gap and rising inequality, as well as details on which sectors are most affected.  

How much overtime do you put in and do you feel it’s the right amount for maximum productivity?