Rafael Cabrero lost 219 pounds by using the low-cost company gym at Verizon Wireless. (Amanda Voisard/THE WASHINGTON POST)

Rafael Cabrero, a customer service representative for Verizon Wireless in Laurel, lost 219 pounds in 11 months using the company gym and the services of its three trainers at a cost — to him — of $15 a month. As the weight came off, Cabrero’s blood pressure fell and his aching back and knees improved.

Cabrero, 37, has little doubt about the value of employer-provided fitness programs. “It’s kind of simple,” he said. “I don’t have to go one place and then work out” before traveling to work. It’s three flights up from the gym to his office.

Companies large and small seem to be reaching the same conclusion. Even as hard times have forced them to trim some employee benefits, corporate fitness programs have survived mostly unscathed and have expanded in many cases.

The number of companies with 20,000 or more employees that provided fitness centers, subsidies or discounts grew by 11 percent from a year earlier, according to a 2010 national survey by Mercer, a benefits consulting firm. Another survey, by the Society for Human Resource Management, shows that the proportion of companies offering gym benefits has held steady since 2007. During the same period, many employers were paring retirement and other financial benefits because of the recession.

The reason, according to many studies, is that wellness benefits provided in the workplace yield more productive employees who require less health care. That translates into savings on health insurance for companies and workers.

“It’s not just the employer saying, ‘We’re going to do this for you out of the goodness of our hearts,’ ” said Paul Fronstin, director of health research programs for the independent Employee Benefit Research Institute. “They’re hoping to get something out of it. And that something is [the health] of this employee, who’s not just more productive, but uses less health care.”

A 2010 Harvard Business Review article found that wellness programs, of which fitness is a component, can return as much as six times their cost to the companies that sponsor them. Another 2010 review by a separate team of Harvard researchers, published in the journal Health Affairs, concluded that “medical costs fall by about $3.27 for every dollar spent on wellness programs and that absenteeism costs fall by about $2.73 for every dollar spent.”

But that sentiment is not universal. Skeptics have long worried that employees already inclined toward a healthy lifestyle are the ones who take advantage of benefits such as fitness classes, which, if true, would limit their effectiveness for the workers who need them most.

The Congressional Budget Office remains uncertain that research has proven the value of wellness programs. “Evidence regarding the effect of wellness services on subsequent spending on health care is limited, and CBO is continuing to evaluate the evidence that does exist,” Director Douglas W. Elmendorf wrote to then-Rep. Nathan Deal (R-Ga.) in 2009.

Research also has found that small companies are much less likely, or able, to offer fitness programs and other wellness benefits.

Even the best research cannot pinpoint which wellness programs provide companies the most bang for the buck. Is it the yearly health risk assessment that workers value most? The smoking cessation group? The 24-hour gym?

After reanalyzing 32 of the best studies, the Health Affairs researchers concluded that their work “cannot address the important question of which attributes of wellness programs are most important. . . . Indeed, the answer might not be the same everywhere.”

Ann Mirabito, one of the authors of the Harvard Business Review article, wrote in an e-mail that “the jury is still out” on the effectiveness of individual fitness programs.

“Our conclusion is that single programs (e.g., fitness subsidies or Weight Watchers) may be helpful but are unlikely to generate the big returns. Most important is creating an overall atmosphere that encourages wellness,” she wrote.

That usually starts at the top, researchers have found, and must be communicated repeatedly in various ways throughout the organization — a task that sometimes is more difficult than it sounds. Mirabito’s research shows that successful private-sector wellness programs require “constant communication that’s engaging and informative, wellness champions throughout the organization,” and goal-setting and assessment much like any other aspect of a business.

But mostly gone are the days when fitness benefits were considered nice perks that companies could offer workers. Many business executives, especially at larger companies, have concluded that wellness works for them as well.

Fronstin recalls one gathering where employees waiting outside a meeting room took off their jackets and began walking the hallways, part of a fitness ethic the company was trying to instill. Johnson & Johnson, often cited as a leader in wellness programming, expanded some of its offerings despite difficult times from 2008 to 2010, said Fik Isaac, vice president of global health services. That included a $150 benefits bonus for overweight employees who could reduce their body mass index by 10 percent.

The company, with 115,000 employees worldwide, self-insures for health care. It concluded in one review that its wellness programs slowed the rate of increase of its health-care costs by $565 per employee.

Citigroup debuted a new wellness program not long before it became one of the firms directly involved in the 2008 financial crisis but decided not to trim wellness benefits, said Niko Triantafillou, vice president for wellness and health plan strategy. The company says every dollar spent on wellness returns $2 to the company, which has 236,000 employees worldwide and is self-insured.

At the Verizon fitness center, trainer Dave Schwalbe uses Cabrero to lure other employees. Cabrero, who is 6-foot-7, weighed 495 pounds when he signed up in September 2009. At first, he could only walk slowly on a treadmill and ride a stationary bike. Now he runs three or four miles, does sprints, jumps rope and bench-presses 225 pounds. Cabrero also swims elsewhere, does martial arts and is enrolled in the Nutrisystem commercial diet program.

About half of the facility’s more than 700 employees are enrolled, and spokeswoman Melanie Ortel said the company has “increased some of its offerings over the past few years,” adding Pilates, yoga, Zumba and walking groups.

Cabrero’s motivation also has a more personal element. He saw an aunt die early at nearly 700 pounds. He was ordering ever-larger clothing. He was developing sleep apnea. Even now, he keeps a photo on his cellphone that shows how he looked before he lost weight.

Cabrero said his weight has inched back up to 290 pounds and he has set a new goal of 240. He may try to run a 5K.

“For me, I see it as something I had to do,” he said. “I don’t feel like anything special.”