So, why did Seinfeld *really* shave his chest?

I heard that the J-man got a lot of slack for being a bit "chunky" after the 1st episode where he was shown shirtless outside of the health club pool with Newman. I'm not sure of the exact episode, but Jerry and Newman were debating over who was going to give mouth-to-mouth to the pool boy. Anyway, I guess after that episode Jerry hired a personal trainer and designed his own personal gym within his home to rid himself of the image. After a few seasons of following a strict diet and weightlifting regimen, his trainer suggested that he bare his chest again. However, this time it would be a full shot of his shaven chest in order to emphasize the definition in his pecs. Anyone else hear this?