On the long-running sitcom "Seinfeld," Jason Alexander played the bumbling George Costanza, who always seemed as if he needed a motivational speaker to psych him up to get through life.

But considering Costanza's multitude of foibles, he would need the best motivational speaker in the business. And Donny Clay is not the best.

Beginning Feb. 11, Alexander will portray Donny Clay in a one-man show where his character is known as "the world's fourth- or fifth-best motivational speaker, depending on where Richard Simmons is that day," Alexander said.

The Tony Award-winning Alexander will perform "motivational" seminars at Las Vegas' Planet Hollywood Resort and Casino, in a show that includes comedy, music, improv and, not least, partial nudity. The run will continue through March 14.

Alexander's send-up of the psychobabble that passes as self-help was inspired after he was asked to do corporate speaking engagements because of his success as an actor. "I didn't think John Deere wanted to hear show tunes," he said. So while he played it straight at the corporate gigs, he came up with the idea of a parody of the Dr. Phils and Anthony Robbinses of the world.

Donny Clay -- complete with a toupee -- was born from that idea, and though he has performed the one-man show several times across the country, this will be his first engagement in Las Vegas as Clay.

"What we are selling is not stand-up," said Scott Zeiger, co-CEO of BASE Entertainment, the show's producers. "What I like so much is the personification of the character, and not so much a standard comedy monologue."

Alexander was quick to caution that he wasn't altogether "pooh-poohing" the idea of personal empowerment through motivational speeches. But he said he has seen his share of bad motivational speakers, as well as those who don't practice what they preach.

In a word: Clay.

After performing the character a few times, the actor realized unintended consequences. "Some people came up to me afterward and said that although they knew [I] wasn't intending it, [they] got something out of this," Alexander said. "[I told them] you must need therapy."

The one-man show offers customers something different from the expensive spectacles that dominate Las Vegas theaters, Zeiger said. In addition to not being another Cirque du Soleil show, prices for Alexander's show are relatively low, Zeiger said.

Production values for Cirque or other shows, such as "Phantom of the Opera," might necessitate high ticket prices, but Alexander's one-man show caps ticket prices at $90, Zeiger said.

An added benefit for Alexander is that the physically demanding rehearsals have helped him lose weight. In January, he signed a contract to be a spokesman for Jenny Craig, and during the first three weeks of the year, he lost 11 pounds.

The show is a lot healthier than, say, playing poker. "It's better than sitting on my a-- [during] my other Vegas activity," Alexander said.

A comment that makes it sounds like received wisdom from a motivational speaker.

dburger@sltrib.com