Jessica Alba has apparently been using a gruelling training regime developed by the Israeli military to get in shape for her movies.
The Sin City actress is known for her honed physique and needed to be in tip-top condition for upcoming action thriller Mechanic: Resurrection.
Her trainer Michael Margolin has now revealed to People that Jessica, 33, achieves her enviable shape partly through the tough hand-to-hand combat technique Krav Maga, which involves wrestling, boxing, street-fighting and martial arts.
Michael - the co-founder of Krav Maga Worldwide - said: "It gets you in good shape and you're also learning a skill."
Mum-of-two Jessica eats well and does plenty of exercise, and works with Michael up to four times a week as well.
He explained: "We do a lot of mitt work where she's kicking and punching various targets as strong as she can for a period of time, and then she rests for a period of time. We also mix in medicine balls, kettle bells and some light weights."
"Jessica works hard, and that's on both the diet and the exercise part," he added.