Smart phones give us instant Internet access and e-mail connectivity.

They're also making us work more.

A British employment law firm, Peninsula, surveyed 600 white-collar workers and found that BlackBerry-equipped employees worked an average 15 more hours a week than colleagues without smart phones.

This does not surprise Beth Stuever, a Michigan State University Extension Services communications manager. She says the iPhone she purchased three months ago has "revolutionized the way I work."

"Do I spend more time working outside the office? Well, yes. But it's in small bits and spurts, and I feel that it makes me productive when I'm in the office because I can take care of small issues quickly," says Stuever, 41.

Stuever's carpool commute is 45 minutes.

"Now, instead of that being anxious time about me wondering what's going on in the office, I can actually get work done," she says. "I clean out the e-mail ... , check in with my Facebook friends and read articles of interest that people have Tweeted."

Ari Adler, a communications administrator for Delta Dental, says he works more because of his smart phone.

"But I don't necessarily see that as a bad thing," says Adler, 41, of Okemos, because he's accessible without being tethered to his desk.

"It seems to me that in today's fast-paced world, the 'work-life balance' has to be a 'work-life blend,' if you are going to be successful on the job and at home," says Adler.

While the technology increases flexibility, MSU professor Ellen Ernst Kossek, who teaches in the School of Labor and Industrial Relations, says the blurring of the line between home and work can increase stress.

"People are afraid of not looking committed. If you have times you're not available and you have a co worker who will answer instantly, it's another way of getting one-upped at work," Kossek says.

Set boundaries so that you're not always "on call," and looking at your phone screen, says Kossek. When you're home, focus on hobbies, family and relaxation.

Kossek suggests that if you feel compelled to check work e-mails on weekends, for example, let clients and colleagues know you'll be available from 6 p.m. to 8 p.m. Sunday.

Adler also says he's had to restrain himself from focusing on his phone, acknowledging it's sometimes a struggle "to be able to just walk down a sidewalk and look around ... and not reach for my belt to look at the phone."

Adler got married over the weekend to Jessi Wortley. It wasn't part of the vows, but Adler says his bride did "give orders about how often she can see the phone out."

(c) 2009, Detroit Free Press.

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