He needs to be bulk up for his new movie role as Boston's most wanted bank robber. And his favorite trainer has a fitness center in Andover.

So, Hollywood actor Ben Affleck dropped by Walter Norton's IP Fitness center on North Main Street (where Taylor Rental used to be) last Saturday morning at 8:30 to the delight of staffers and early workout risers.

Dressed in a gray T-shirt, and red shorts with a Harvard University football logo and holding a water bottle, Affleck was relaxed and comfortable after his private work out session with Norton. He posed for numerous pictures and shared small talk with the crowd, prompting everyone to admire his good sportsmanship.

"Are you guys any good?" he asked while posing with members of the Andover High School football team.

Football captain Andrew Lebowitz strolled over to the fitness center from his nearby job at Sunoco Service Station and had his picture taken with the Hollywood actor.

"Cool," was all he said.

Affleck also posed with members of the school's basketball and baseball teams.

Meanwhile, the females went ga-ga over his bearded good looks.

"Did you see his teeth? He has really nice teeth," said Morgan Cambern, who works out regularly with Norton.

"Walter has relationships with all of his clients, so I'm not the least bit surprised to hear about this," she said. "It's just so Walter."

Norton billed it as a way to thank his clients, calling it a "customer appreciation" event. He just worked his phone, announced the movie star's presence, and the people came.

Affleck said Norton's down-to-earth personality and motivation is why he agreed to come to Andover. Affleck said he started working out with Norton about four months ago. He is filming a movie called "The Town" around Boston and Charlestown and said he hooked up with Norton to build muscle for his movie character, a bank robber.

Jon Hamm ("Mad Men") and Rebecca Hall ("Vicky Cristina Barcelona") also star in "The Town," a romantic crime drama that Affleck is also directing. Based on Chuck Hogan's novel, Town, Affleck has an FBI agent hot on his bankrobbing trail and both men fall in love with Hall, a bank teller.

If he were on the West Coast, Affleck said he would have to hook up with an athletic trainer who works exclusively with a movie star or two and it would be all about publicity. On the East Coast, it's different.

"Here, I get to talk with regular people and work out with a regular trainer and I really like that," he said.

"I wanted to see Walter's gym and see some kids, see what they are doing," said Affleck, an avid Red Sox fan and all-around sports enthusiast. "Helping kids in the community is important. Walter does a lot of community service and I really admire that."

When reminded about his wife's appearance in Andover last year, he smiled and encouraged people to see her soon-to-be released movie.

His wife, Hollywood actress Jennifer Garner, appears in "This Side of the Truth' with Ricky Gervais and Rob Lowe. Filming took place in a mansion on Regency Ridge in June 2008.

"That's right, she was in Andover," Affleck said. "Go see her movie...make sure you see it."

"This Side of the Truth" is scheduled to come out on Sept. 25.