REDONDO BEACH, Calif. — Marc Cleary is not a dog walker. Rather, he is a “personal dog trainer.” And, like those who motivate humans, Cleary’s job is to push pooches to their limit in the gym.

“(They need to) build muscle, get strong, keep the heart healthy,” Cleary said from his mobile fitness gym — a van equipped with a doggie tread mill.

At a time when statistics show more than 50% of dogs in the U.S. are obese, Cleary has clients whose dogs need more than just a “walk.” His Bark N’ Roll Mobile Dog Fitness service offers a full cardiovascular workout.