Early one morning in late August, dental assistant Lynda Bergeson could be found in the "Total Conditioning" class at the Highland Park Life Time Fitness in St. Paul. The 57-year-old devotes part of her work week to exercise -- a practice that has left her feeling better and more capable of managing the rigors of her job.

"I just feel better about myself and I feel that I'm a more productive employee," said Bergeson, who works in St. Paul. "My day goes better after I have a workout." Bergeson's boss helps out in his own way by allowing her to come to work a little later on the days she attends exercise classes.

Bergeson is part of a growing trend toward improving wellness of employees. While she's taken the initiative to stay in shape on her own, many companies are encouraging their employees to hit the gym in an effort to stem rising health care costs and to help colleagues deal with challenges such as obesity, stress, disease, poor eating habits and smoking.

The total cost of obesity to U.S. employers is $13 billion per year, according to the University of Michigan Health Management Research Center. The university also reports that job stress costs $200 billion to $300 billion annually in lost productivity, tardiness and absenteeism. A 2003 study by HR specialists Ceridian Corp. found that corporate wellness initiatives cut short-term sick leave by as much as 32 percent. And according to a study by the Federal government's Centers for Disease Control and Prevention in Atlanta, a good corporate wellness program will result in $3 to $6 saved for every dollar spent.

Businesses are getting the message.

"I think wellness is always been something corporations have been aware of because they care about their workforce, but it's often been window dressing," said Jess Elmquist, Life Time Fitness' senior vice president of corporate wellness. "But now companies are seeing it as a key component [of] the health of their business and managing health care costs."

"What a lot of our customers are dealing with today is their aging workforce," said John Waters, director of wellness consulting at OptumHealth in Eden Prairie. "We have customers who target that specific group with 'silver sneakers'-type programs, where they focus on physical activity to get their workforce moving."

Improved health among employees leads to less absenteeism, said Elmquist. Fitter employees eating better food leads to weight loss, fewer sick days and greater productivity.

Life Time Fitness offers a virtual tool called "myHealthCheck" that provides health assessments, online coaches, blogs, social media and other resources. Employers can use the system without having their employees join the Life Time Fitness club, says Elmquist, and it offers a "challenge engine" to keep employees engaged.

Life Time is just one of many players in the corporate wellness world. For example, RedBrick Health in Minneapolis and OptumHealth offer employers wellness programs that provide health assessments, coaching, health portals and other features.

In the case of OptumHealth, employees who agree to participate in a program to, say, quit smoking or lose weight can receive financial incentives from their employers that take as much as $600 off their annual health insurance premium. People will enter a program when they see savings of around $400 on their premium, Waters said.

Other programs dangle smaller incentives, such as cash, T-shirts and sweepstakes. "It's about how do you get them to care," Waters said. "Employers are using the incentives to engage the employees to take a health assessment, go to a biometric screening or take advantage of a disease management program."

Not all employees need an incentive -- or even an employer willing to pay for workout courses. Linda Simon offers yoga classes at locations in downtown Minneapolis and St. Paul through her Minneapolis-based business, Fit To Live, and her participants rarely get an employer subsidy.

"The 50-plus age group I see is thinking, 'Gosh, I want to be in good health when I retire', and that's part of the reason they take our classes," she said. "It's also about quality of life -- they want to be physically fit, they want good nutrition and they want a way to deal with stress."

Having the lunchtime classes seems to work well with the schedules of many employees who work downtown. Simon believes it is harder for many people to exercise before work or after they go home. A lunchtime workout breaks up the day, she said, and allows people to start the afternoon more relaxed.

For Bergeson, her exercise routine changed her life.

Fourteen years ago she was mom in her 40s who had fallen out of shape. In 1997 she began hitting the gym regularly, and her improving fitness eventually led to a winter gig teaching downhill skiing at Afton Alps.

Bergeson's motto is simple: "I think you should be as healthy and fit as you can for the age you are."