From grocery store clerks to high-powered Wall Street types, the same malady is hitting workplaces nationwide: burnout.

Cell phones, pagers and e-mails are partly responsible. The ability to be available to bosses and co-workers 24/7 is a strain on nearly everyone. But the other big culprit of workplace stress is boundaries — and our unwillingness to set them, says Mike Staver, an executive coach.

"You're the one who has to turn off the cell phone, who has to turn off the pager," Staver says. "But you can't seem to do it because it's like a needle to an addict. So instead of being a human being, you're a human doing."

That's why Staver advocates that workers set boundaries in a way that makes more sense — one day a week, the cell phone and pager and e-mails are turned off at a certain time.

Staver, who often advises executives on ways to reduce their stress and avoid burnout, says that he sees the same problems reflected in every segment of the American workplace. Burnout, he says, "happens when the investment of energy exceeds the return on investment."

So instead of feeling like time flies as you put your energies into a task, you feel a decreasing sense of energy in tasks or relationships, finding that you get less fulfillment out of things you used to enjoy. You either work at a frantic and distracted pace, getting less and less done, or you just generally slow down your pace.

"It shifts from something you pursue to it pursuing you," Staver says.

Still, Staver says, there are ways that workers can get a better handle on their stress and avoid burnout. He says that everyone should begin each day by investing in one "high-gain activity."

"This is what a person decides would supply them with fuel and energy," he says. "For some, it may be yoga or jogging, but I know one woman who begins her day by reading. That's what she really enjoys, and that's what gets her started."

Staver suggests that listening to music that "pumps you up" is also a good idea, because research has shown that people who use this strategy before they face challenging situations increase their productivity by as much as 200 percent.

Some other ideas to avoid burnout: