Jennifer Aniston took a break from filming The Bounty on Aug. 22 to enjoy a meal with co-star Gerard Butler and some pals at Freemans eatery on NYC’s Lower East Side. Instead of nibbling on a salad, “she shared her dessert with her table and drank with her friends.” “She’s tiny, but she looks strong and healthy. Her arms were amazing, she was in great shape and she looked comfortable in her own skin.”

“Whenever she wants to look her best, Jen does this strict diet so she’s able to lose 5 pounds in five days,” an insider on the set of The Baster (a comedy Jen filmed with Jason Bateman before The Bounty) tells.”She did it during her past few films and doesn’t find it hard at all. I saw her eat pasta only once!” But the yoga devotee who flew her instructor, Mandy Ingber, from LA to her NYC set always eats enough to keep up her energy.

“She routinely gets up at 5 in the morning to run before filming starts,” says the insider, who was on set with Jen as she filmed The Bounty at Monmouth Park race track in Oceanport, N.J., on Aug. 17. “We were filming from 6 a.m. until almost 11 at night, and she had a great energy level the whole time. She was upbeat and smiley and never flubbed a line and her body looks amazing!”