MSN cites Twilight as part of a trend where stars have to tone their bodies to depths never before considered in the acting field.

“The Era of the Buffed Actor is upon us, which means no significant male leading role is exempted from the expectation that he have rippling biceps and six-pack abs. That’s Hollywood.

Whether it be Matt Damon in the “Bourne” films, Jake Gyllenhaal in “Prince of Persia,” Russell Crowe in “Robin Hood,” Robert Pattinson and Taylor Lautner in the “Twilight” series, Robert Downey Jr. in the “Iron Man” pictures, or many others, flab is clearly not fab.

Celeb workout The making of an action hero body personal trainer Michael Torchia shares the 4-day split workout program he uses when getting celebrities ready to play hard-bodied heroes.

Actors in action or physically demanding roles are defined these days by their definition.”

See more on MSN. Do you think this rigorous training is necessary for all movies?