(Bloomberg Business) — Swedish trucking company Scaniabelieves in the 24-hour employee. Scania workers aren'tjust expected to be their best selves at work, they're expected tobe their best selves all the time. To help employeesattain that ideal, Scania offers anextensive workplace wellness program to its5,000 employees that includes access to an onsite gym, a team ofhealth care professionals, and seminars in which employees canlearn techniques for healthier living.

"Scania cares for its employees both on and off thejob," a human resources manager in 2011 told aresearcher of its approach to workforce wellness. "We try tohelp them live healthier. Our interest and care does not end whenthey leave work."

But according to researchers Andre Spicer and CarlCederström, Scania's efforts didn't always have the intendedeffect. Over the last 4 years, the two have studied wellnessprograms at hundreds of companies, including Scania. In their newbook, The Wellness Syndrome, they describe how the company'sextensive wellness efforts stressed some employees.

Because employees had every opportunity to stay healthy, thosewho didn't meet extreme health standards sometimes felt likefailures.

"We noticed that they would begin to worry about their level ofexercising," Spicer said. One employee interviewed by thebook's authors said that he felt the need to stay fit tokeep his job: "In these times when people are laid off due tothe global financial crisis, you need to stay fit, and the healthprofile helps you do so."

More broadly, Spicer and Cederström found that more extremecorporate wellness programs such as those at Scania lead toincreased anxiety and stress.

"In the Scania case, they said: 'I have to exercise or else I’mnot going to be seen as an attractive employee. I’m not goingto just be a bad person, but an unemployable person,'" said Spicer,who studies organizational behavior, psychology, and sociology ofwork at the Cass Business School in London.

As health-care costs grow, many companies in the U.S. haveinvested in some kind of wellness initiative, hoping for ahealthier (and therefore cheaper) workforce. A2013 analysis by the RAND Corporation found that half ofall organizations with 50 or more employees offeredwellness programs.

The thinking goes that getting at-risk workers to change badhabits will save a company on medical costs down the road. Theprograms differ, but often include such elements as smokingcessation assistance, biometric screenings, and fitnesschallenges. According to a Kaiser Family Foundationsurvey from last fall, 36 percent of large companies offeremployees health insurance discounts for weight loss andsmoking cessation. Health riskassessments are even more popular, the study found, with more thanhalf of large companies providing a financial incentive forparticipation.

Despite the growing popularity of wellness programs, it'snot clear that they work.

Corporate wellness is an $8 billion industry; as of 2013,employers spent $2 billion on wellness initiatives,as Bloomberg reported in 2013.

While one Harvard study from 2010 found more than $3 in savingsfor every dollar spent, more recent research by RAND estimated thatfigure at $1.50.

The same RAND study found much higher savings fordisease management programs, as did this study of a successfulPepsi wellness program that, in part, targeted participants withailments that include asthma, coronary artery disease, atrialfibrillation, and diabetes.

More extensive programs that include preventive measures,however, can actually have unhealthy outcomes, largely bytriggering feelings of anxiety, Spicer and Cederströmfound.

"This increasing pressure ... is not just formal in terms of thewellness programs, but informal in terms of social pressure to workout and be extremely fit in the workplace," Spicer said. "That thencan have some psychological effects. There is this implication thatyou don't just need to have a work ethic, but a workoutethic."

Most companies aren't as overbearing as Scania, but Spicersays that wellness programs have become more aggressive. In some Danishmunicipalities, for example, employees can participate insessions with consultants to learn better eating habits.In their book, Spicer and Cederström refer to such programsas "fat therapy." Such initiatives might lead toweight loss, but they publiclysingle out some workers, and, the two say, imply a lack of selfcontrol.

An employer might care less about triggering anxiety thanstamping out more concrete risk factors. Still, havinganxious employees misses a major aspect of wellness. "Many peoplehave bought into the argument that the fit employee or the happyemployee is the most productive employee," he said. "[But] wellnessis happiness and health."

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