Milo Ventimiglia recently sat down with Men's Fitness to discuss physical fitness, his career, and his character on Heroes.

In the interview, Ventimiglia talks about his slender physique during the beginning of the show's first season:

"I was very slightly built. I didn't have a lot of man weight on me," says Ventimiglia. "I wasn't really grown up." Ironically, that may have actually helped him land his role. Show creator Kring was specifically looking for an actor who could play someone on the cusp of manhood. "When we first meet Milo's character, Peter," says Kring, "he's a bit lost and unsure of what his role in life is. Then, through the course of the season, he had to go from that to becoming a leading man. So he had to grow into that."

And grow into it he did. According to the article, a self-created workout plan added nearly twenty pounds of muscle mass to Ventimiglia during the course of the show's first season. This increase in Ventimiglia's physical fitness also helped with the course of the second half of the season:

Getting fit also paid off for the show, which, as a fast-paced, sci-fi action series, is one of the more physically demanding productions around. "I get beat up, I'm bloodied, I'm in a flying harness, I'm knocked down. I've definitely had a lot of bumps and bruises," says Ventimiglia, who does the lion's share of his own stunt work. "I've got to keep myself strong and flexible and in the right state of body to do a lot of those things." Says Kring: "I don't think we would have written a lot of the stuff that we did in the second half of the season had we not seen what Milo could do physically."

CLICK HERE to read the entire interview.

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