Maintain boundaries between work and home. Some obvious tactics come to mind: Turn off the cell phone during dinner. Don't plan the T-ball lineup at budget meetings. BlackBerrys stay home during family vacations. But you need mental boundaries as well. It's important to take time to reflect and regroup, even at work. Create "sacred spaces" throughout the day, suggests David Astorino, a Philadelphia management psychologist with the consultancy RHR International. It could be 10 minutes with the office door closed or a long walk after lunch. For Zeigler, it's the half-hour every morning she sets aside for the gym. "That one thing really helps the most," she says. "It keeps my mind straight, gives the body stamina."

Stick to a schedule. A set routine helps keep your boundaries—and your mind—clear. On top of his 10-hour workday, Akshay Upadhye, a London-based IT consultant with Source Paradigm Limited, allots an hour every morning for meditation and yoga and three hours each evening for his wife and two young kids. Weekends he devotes to the family. "I follow a very simple rule," he says. "When at home I don't think or worry about work. I only think business the moment I get into my car. ...The moment I enter my home, I switch off from my work." He gives yoga the credit for teaching him to control that mental on/off switch.

Priscilla Ribic of Spokane, Wash., is a project manager for Financial Partners, a single parent to her 12-year-old son, and an international powerlifting champion (check out her impressive stats at her website, littlepowerhouse.com). A defined schedule helps her navigate between work and her personal life. "One nice thing about being a project manager is that you can't help but be organized, work time lines, set goals and so on," she says. "My days start early—5 a.m.—and end late—11 p.m.—and it's nonstop all day, but my day is fairly structured, making it all manageable."

Delegate. You don't need to do it all. Really. "It took a while for me to figure it out," says Ed Longanacre, senior vice president of IT at Amerisafe in Deridder, La. "[But now] I've got these guys trained well enough that I don't need to be there all the time." Upadhye has empowered his subordinates to make certain hiring and salary decisions, handle delivery management for shorter projects and conduct weekly client reviews, for example. "This ensures that I am not spending energy and time on unwanted things," he says.