By Derrick Blakley

CHICAGO (CBS) — Surveys show most school bus drivers are on the road to serious health problems. In fact, one study found almost 9 out of 10 are overweight and almost half are obese.

CBS 2’s Derrick Blakley found a local bus company that’s helping its workers slim down.

Even when their bus is empty, far too many school bus drivers carry a heavy load. That’s what bus corporation Cook Illinois found, when they offered voluntary health screenings.

Steve Miller says they indicated drivers showed signs of being pre-diabetic and had hypertension above national averages.

Excess weight is to blame.

“We’re sedentary all day. We sit in a school bus at least four to six hours a day,” driver Paul Leahmann says.

Between morning and afternoon runs, many drivers sit around the break room, playing cards and eating. The company is encouraging change.

Bus monitor Sallie Bell has lost 14 pounds in less than three months.

“I do feel a difference, because I have high blood pressure. My blood pressure has come down tremendously,” she said.

Sallie and other employees exercise between shifts with company-subsidized memberships at a health club.

Yvonne Arias has lost 18 pounds.

“Now when we come back, we got to the health club instead of just sitting there,” she said.

Other employees hit the road, walking outside, or inside shopping malls.

At the vending machines, junk food is out, healthier options in.

And there’s a biggest loser competition for who can drop the most, with weekly weigh-ins. The winner will get $500.

“But it’s not about the money, it’s about having better health,” driver Daryn Greene says.

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