20/08/2014 12:52 BST | Updated 20/05/2015 10:12 BST

Jennifer Aniston's Yoga Teacher Reveals The Star's Workout Secrets

When she's not on set filming her latest movie or deciding when and where she will eventually tie the knot with fiance Justin Theroux, Jennifer Aniston can often be seen on an exotic holiday, wearing a bikini and looking incredible.

Jennifer Aniston arriving at the European Premiere of We're The Millers, Odeon West End Cinema, Leicester Square, London.

So, how does the 45-year-old star stay in shape? Her yoga teacher has just shared a few secrets.

In an interview with ABC News, celebrity yoga instructor Mandy Ingber revealed how Aniston "tightens up" before jetting off on her romantic getaways with Theroux. (The couple have recently been holidaying in Bora Bora to celebrate their second engagement anniversary. Yes, engagement anniversaries are a thing now.)

"Jen's a very consistent exerciser and eater," Ingber, who also works with Kate Beckinsale, told ABC. "But when she has something she needs to focus a little more on, she just tightens it up a little bit."

Tightening up means no snacks. "She won't have the extra chips," Ingber added.

MORE: Jennifer Aniston reveals her biggest body hang ups

NEW YORK, NY - JUNE 23: Actors Justin Theroux and Jennifer Aniston attend 'The Leftovers' premiere at NYU Skirball Center on June 23, 2014 in New York City. (Photo by Jim Spellman/WireImage)

Next comes the grueling exercise routine.

"We up the cardio a little bit, if she's looking to sort of trim down," she said. "So we add a little more cardio to the yoga, but also what she puts into her body is essential. That really is 80 percent of it ... it's not a big deal if you have a bite of this or that if you are mostly eating well."

As for Aniston's body hang ups, Ingber indicates her bum is Jen's biggest issue.

"She focuses on butt exercises for sure, I'll add some squats into the yoga routine," she said. "For me, there's no better thing to lift your butt than squats. Pretty much, that's gonna do it ... she likes to focus on that like most women. Most of us want that area a little higher."

Yoga, squats and no chips. She makes it sound so easy.

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