David Alan Grier has been working up quite a sweat on Dancing With the Stars.

"I've actually lost 26 pounds," the actor, 53, told Usmagazine.com after Monday's show. "The first day I came in, I was like, 'I'm not going to

lose weight - we're waltzing!'"

See funny photos of the new DWTS cast rehearsing (Steve-O puts a bike on his nose)

But he said his dancing routines with partner Kym Johnson involve "three hours of aerobics. You're dancing and you're using your core - which Kim was talking about."

See Us' weight winners of 2008

Added Johnson, "You're burning a lot more calories because you're actually moving your whole body, as opposed to doing just weights."

Grier - who had been on a strict diet of egg whites, fruit, yogurt - said he now "can cheat a little bit because we are burning so much."

See photos of hunks who have packed on the pounds

Two contestants go home on tonight's show - and Grier (who scored a 22 for his Lindy Hop on Monday's show) is hoping he is not one of them.

"I have to stay in to lose four more pounds," he told Us, "and then you can kick me off."