LOS ANGELES -- Like any true celebrity, Uggie, the Jack Russell terrier from The Artist and Water for Elephants, puts in his time on the treadmill.
At 10, Uggie doesn't do a heavy workout, just a light trot and walking, said owner-trainer Omar Von Muller of Los Angeles. But Von Muller bought Uggie a DogPacer for those times when he can't go out because of weather, work or paparazzi.
"It's important to keep him in shape," Von Muller said. "If they don't get their exercise, they get old too fast, just like people."
Some 3 million dogs across the country were using treadmills in 2010, according to a survey of pet owners by the American Pet Products Association. The group asked about treadmills for the first time in its 2011-12 survey because the machines were selling so briskly, APPA President Bob Vetere said.
It may look like the dog is going nowhere. But pet owners with fat, old or misbehaving dogs say they measure the benefits of canine treadmills in pounds, years and sleep.
Heather Chau borrowed a DogPacer when her rescue dog Heidi arrived weighing 115 pounds. Heidi is now down to 80 pounds, and Chau, a Las Vegas bookkeeper, was so impressed that she returned the donated DogPacer and bought her own.
Now all four of her dogs use the treadmill. Chau explains that she can't walk four dogs at a time, and summer in Las Vegas heats up early and winds down late.
"I want to make sure the rest of their lives are the healthiest we can make them. If the treadmill promotes a longer life, then it's easy to do it each day," Chau said. "Whatever they have been through is in the past. Whatever we can do now to help them lead a healthier, better life is worth it."
Treadmills come in a range of sizes and prices.
At LA Dogworks in Los Angeles, owner Andrew Rosenthal has a DogPacer, one of the newest and least expensive on the market at $499, that his Alsatian German shepherd Josh likes to use.
Rosenthal's 24-hour dog-care center, which offers boarding, grooming, training, daycare, hydrotherapy, massage therapy and a retail store, also uses a $3,000 Jog A Dog and a $40,000 underwater treadmill.
The most visible difference between a human treadmill and a canine treadmill is the size, because a dog's stride is longer and his body shorter than a human's, said David Ezra, the owner of Las Vegas-based DogPacer.
DogPacer plans to release a treadmill for toy dogs in September, and the price will be smaller too, Ezra said.
Pooch Hotel in Los Angeles, owned by Petco Animal Supplies, offers a treadmill to help keep pets in shape.
About half the dog population has some kind of weight problem, so it was a no-brainer, said Jason Michal, who runs the hotels as Petco's vice president of pet services and hospitality.
For home use, Pennsylvania-based GoPet has canine treadmills and a TreadWheel, which looks like a giant hamster wheel, for small to large breeds, ranging from $475 to $1,225.
Dog trainer April Suhr of Las Vegas believes that shelters across the country could make animals more adoptable if the animals used treadmills just two or three days a week.
It's easy for a dog in a shelter to go cage-crazy, she said.
"They pace. They don't focus. They bark. They won't eat. They won't make eye contact."
The answer is exercise, she said. "It's why the gym is so good for us when we are stressed out. It puts our endorphins to good use."
Suhr, who volunteers at Adopt a Rescue Pet and has her own business, 4 Pawz on the Floor, also works part-time in a pet superstore. She brought a rescue dog, Max, to the store every week to use the machine.
"Not only did he calm down, but he was using the treadmill one day when a woman came in, saw him, fell in love with him and adopted him," she said.
Suhr has one at her home for her three pets and her foster dogs.