Fat Mac: 'It's Always Sunny' Star Explains Packing on the Pounds

The FX comedy "It's Always Sunny in Philadelphia" never holds back in order to get laughs. With the show's seventh season starting, the laughs are sure to get even bigger with the debut of fat Mac.

Series star Rob McElhenney will debut a new rounder physique for the upcoming season starting tonight. He put on an additional 50 pounds just for comedic effect. Now that's commitment.

Why did McElhenney decide to turn the once trim Mac, obsessed with his "cat-like" reflexes and sleeveless t-shirts, into a more portly figure?

"It came when I was watching a very popular sitcom, and I noticed the people were getting better and better looking as the seasons were going on," McElhenney told the Television Critics Association fall tv previews on Saturday, according to TV Guide. "I always thought that what we were trying to do on "Sunny" was the deconstruction of the sitcom."

How did he manage to pack on all the pounds? With a little help from some famous Philadelpha friends, of course. McElhenney was referred to a doctor by Philadelphia Phillies baseball player Chase Utley, who made an appearance last year on the show.

"I told him that I was gaining this weight, and he said, 'Hey, I've got this nutritionist that I work with, who makes the meals for you, and he can do it in a healthy way.' So I called this guy up, and he's got this company that works with a lot of professional athletes, including offensive linemen," McElhenney told The Philadelphia Inquirer about consulting with Utley.

"And offensive linemen have to gain as much weight as they possibly can."

Instead of going on the all-McDonalds heart-attack diet like "Supersize Me" movie producer Morgan Spurlock, McElhenney wanted to gain the weight in a healthier way. A meal, he explained to The Philadelphia Inquirer was "three chicken breasts, two cups of rice and a cup of vegetables." To pudge-up he was consuming a whopping 5,000 calories a day.

He's now managed to loose about 25 to 30 pounds of his comedy padding but feels it was all worth it. And maybe he's right since the show as just picked up for two additional years by the network, making it the longest running comedy in basic cable history.

What do you think about the change in Mac? Check out the video preview for the new season and tell us your thoughts in the comments: