Jake Gyllenhaal: I am Performed " Working out Frequently "

Fitness fanatic Jake Gyllenhaal is taking a breather.

In the September concern of Specifics , the 31- yr -old actor says his notoriously grueling exercises are a thing of the previous. "I haven't cycled in a long time," he reveals. "I don't run any longer. Do I consider care of my physique and consider conditioning critically ? Yes. But exercising on a regular basis doesn't fit the energy of the character I'm enjoying now," he says of An Enemy, in which he plays a man who seeks out his appear -alike.

Gyllenhaal -- whose renowned exes contain Reese Witherspoon, 36, Kirsten Dunst, 30, and Taylor Swift, 22 -- says he's turn out to be a diverse guy considering that he shot the police thriller End of Watch , directed by David Ayer. "Dave told me proper off that this was going to impact my soul," Gyllenhaal expl ains. "'Friends are going to say, That is the Jake I've generally identified, but someplace deep inside, you'll know otherwise.'"

The actor invested five months prepping for the 22-day shoot, which incorporated " 3 nights a week in ride-alongs with cops," Gyllenhaal recalls. "[We had] fight education each morning at a Kenbo Karate dojo, and I acquired the sh-t kicked out of me. Then [we went to] the shooting array, shooting past each and every other's heads, with live ammo."

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" There is a simulated fire in the motion picture, but Dave needed us to really feel what that's like, so he had us do a managed burn," Gyllenhaal adds. A single Saturday, the actor and his costar, Michael Pena, 3 6, "drove down to Orange County, dressed like firemen head-to-toe, and suddenly we're there just sitting in the middle of a burning constructing."

According to Gyllenhaal, the film -- in theaters September 28 -- inspired him to go with his gut.

" Every single journey starts with anxiety. And I could say that is what I want to embrace now. A authentic expertise," he tells Details . "And I want, overall, to believe in what I know is appropriate. There have been many times when I haven't. It is what I'm asking myself: Exactly where is the line? What is the line? There's so substantially context, it can be virtually extremely hard to uncover."