A lot of media attention over the years has focused on the harmful effects of working long hours. The tragic fate of a woman in Japan who died last year of overwork--a phenomenon known as "karoshi", in Japanese?--?is just another high-profile example that has circulated in the news.

This is not unique to Japan: Logging excessive hours at work is ingrained in the work culture of the West, as well. From Bay Area startups to sprawling multinationals, the ethos at many companies is still centered around how many hours you can clock at work. There is a powerful assumption underlying this ethos too: That the more hours you put into your job, the more you'll get out of it by way of recognition, compensation, and opportunities for advancement within the organization. 

A new study by a pair of business school professors in Europe challenge this assumption, however. From their analysis of nearly 52,000 people from 36 European countries, they concluded that it's not just the number of hours you clock at the office, but how intensely you work during those hours, that affects your satisfaction at work and opportunities for advancement.

By comparing people in similar jobs and education levels, researchers found they were more likely to "suffer poorer wellbeing and inferior career prospects, including satisfaction, security and promotion, when they worked at an intense level for long periods."

Hans Frankort, a senior lecturer in strategy at Cass Business School and co-author of the report, told The Financial Times the research suggests the "career benefits of excessive work effort?--?longer hours or harder work than typical in one's occupation?--may never materialize." 

Employers and government should try to reduce work intensity rather than try to control excessive hours, the authors concluded. "Employers and policymakers focus a lot on the latter, but compared with overtime, work intensity predicts much greater reductions in wellbeing and career-related outcomes," Frankort told The Financial Times.

For employees, there is a range of things they can do to ensure they're working smarter, and not just harder. Beth Belle Cooper, a former content creator at Buffer, the social media scheduling app, suggests taking more breaks to refresh your mind and reset your attention span. She also recommends taking naps, which she says not only help to consolidate new information in the brain, but also helps you avoid burnout. 

You might also consider completely unplugging from work more consistently, and for longer periods of time. This is what Sean McCabe and his small team of content creators does when they take a week-long sabbatical every seventh week. 

"Taking a seventh week off has just been revolutionary. It has changed everything for me. I cannot imagine my life without it...I have no idea how we used to work as hard as we did for six weeks and not stop, have no end in sight, no breaks, no checkpoints, no milestones, no steps back, and no chance to re-evaluate where we are and what we're focusing on."