Gone are the days of strolling into work at 9 a.m. sharp and clocking out precisely eight hours later. American workers are putting in more time on the job than ever before. In a 2014 Gallup poll, 40% of U.S. employees said they work more than 50 hours each week, while 20% put in more than 60 hours.

Of course, nowadays, you don't need to physically sit in an office to perform work-related tasks -- a fact that's both a benefit and a curse. With the ubiquity of smartphones and the ability to access proprietary systems remotely, workers can log on at all hours and respond to job-related demands at any time. Working outside the office is still working, and for the nearly half of U.S. employees who regularly put in 50 hours or more each week on the job, it's a habit that can all too quickly result in a case of serious burnout.

Tired man at his desk

IMAGE SOURCE: GETTY IMAGES.

Part of the problem is that employers tend to put a lot of pressure on employees to be perpetually available, even if that means logging on after hours or on weekends. But companies that demand a more intense workweek might actually be shooting themselves in the foot. That's because a Stanford University study has found that employee productivity significantly declines once the 50-hour mark has been reached in a given work week. Furthermore, employee output falls off a cliff after the 55-hour mark -- in other words, an employee who puts in 65 hours on the job in a given week won't be any more productive than someone who puts in 55.

Not only that, but longer hours have also been linked to frequent absences and an increase in employee turnover. And it makes sense: When we push ourselves too hard, whether by choice or due to pressure from management, we're more likely to get sick or feel the need to run away. If you've reached a point in your career where you're putting in too many hours for your own good, it may be time to scale back -- before you reach the point of no return.

How much are you willing to give up?

It's one thing to forgo the occasional happy hour or miss out on a few family dinners here and there to please management or meet deadlines. But it's another thing to spend so much time at the office that your friends forget what you look like.

Giving up too much of your free time can harm not only your happiness, but also your health. We all need opportunities during the week to recharge, and if you go too long without a reasonable amount of downtime, you risk falling victim to physical ailments as well as depression.

Additionally, the more time you spend working, the less time you'll have available for one of the most important forms of self-care: sleep. In fact, a University of Pennsylvania study found a direct correlation between work habits and sleep. Not surprisingly, workers who admitted to consistently sleeping six hours or less per night clocked in 1.5 hours more per week than those who managed more sleep. Not only can a lack of sleep make you crabby, but it can also impact your productivity on the job.

Working longer hours can cost you in other ways, too. If you're constantly at the office or busy with work-related tasks, you may have no choice but to outsource things you'd otherwise do yourself -- things like laundry, cooking dinner, and cleaning the house.

Imagine that as a result of your work schedule, you wind up spending $200 a month on a cleaning service and another $300 a month on takeout. Since you can clean your own home for free, and prepare your own food for approximately one-third of what you'd pay at a restaurant, all told, you'll wind up spending an extra $4,800 a year to maintain a reasonable degree of human functionality amid your ridiculous work schedule.

Ending the madness

While every job comes with its own peak periods of demand, if you find that you're consistently working more hours than the typical employee, it may be time to re-examine that practice and start making changes. That could mean taking on fewer projects so you're not constantly up against deadlines, or resetting expectations with your manager to ensure you're not being taken advantage of.

Along these lines, you may want to take a step back and think about why you're working so many hours in the first place. Is it because you tend to get distracted during typical working hours? Are you spending so much time in meetings you don't have a chance to sit at your desk and do your actual work? Or are you working yourself ragged in the hopes that the extra face time (or virtual face time) will land you that promotion you've been vying for?

No matter the rationale, there's a good chance you can get away with working fewer hours than you're currently putting in. So if you're tired of feeling like you're married to the job, start cutting back slowly but surely, and find ways to be more productive with the time you do spend at work. It'll be good not just for your sanity, but quite possibly for your career as well.

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