Workaholism Is the Threat That Masquerades as Dedication It used to be a choice to stay late but now the office comes home in your cellphone and laptop. Is any good coming out of this?

You can't miss them -- large, white buses with tinted windows shuttling tech professionals both ways between San Francisco and the southern end of Silicon Valley. One day while stuck in traffic, I looked at the buses and thought, "Why can't these smart companies create an algorithm to avoid sending people in both directions -- thereby avoiding pushing them to start their workdays even earlier while en route to the office?"

And then it hit me. We don't need an algorithm to optimize who works from which location -- we need to reimagine the workday for knowledge workers.

Always-available culture.

For most of my career, I've worked in tech in Silicon Valley. I remember the first time I got a device that allowed me to read work email away from my desk. It felt liberating. Then, as more people got mobile devices, our always-available culture became an everyone-always-on culture. I never realized how fatiguing it was to be on all the time until I got a chance to turn it off.

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At too many companies, there is no chance to turn it off. From the moment employees begin their morning commutes until the moment they check their email "just one more time" before closing their eyes at night, connected teams are working. Work seeps into every part of their life -- their evenings, weekends and vacations. Even their sleep! And many business owners and leaders fuel this norm by operating the same way themselves.

More harm than good.

Studies show that this overwork -- whether management requires it, encourages it or tacitly accepts it -- is detrimental to our teams and our businesses. Is a team that works in always-on mode dedicated and productive -- or perpetually on the brink of burnout?

The downsides can be very real.

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Health problems result.

And health problems lead to more sick days and a revolving door. Studies have shown that people who work more also drink more. They're more likely to be depressed. They demonstrate a link between overwork and illnesses like diabetes and heart disease. Ailing employees eventually call in sick, and when they can't take the pace anymore, they quit -- and that's expensive for companies.

Tired employees don't do good work.

The difference between working 40 hours per week and working, say 55 or more, shows up in the quality of the work. In the "80s, the Whitehall II study in Great Britain highlighted a drop in cognitive function for those working longer schedules. Teams that spend more hours at their desks but get progressively less effective aren't benefiting the business.

Overworking doesn't create a noticeable difference.

We can't tell the difference between employees who overwork and those who don't. This was the finding of a Boston University business professor who studied consultants. Do you know whether your star performer is actually working 70 hours a week -- or just pretending to in order to impress you? Research shows you probably can't tell the difference.

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These are the things that go through my mind when I see those white buses rolling through Silicon Valley, carrying knowledge workers who are "maximizing their days" by working through long commutes. As their days expand, the value these professionals deliver for their companies actually decreases. Ending this toxic workaholism -- and building a healthier workforce and healthier companies -- will require a loud, clear, honest call to action from the top. We need to lead by example and say to our teams, "Whatever work is following you into your evenings, weekends and vacations -- it can wait."