Jennifer Aniston’s personal trainer revealed the secret behind the 55-year-old star’s incredible body.

Speaking to Dani Coleman, Jennifer Aniston’s Pvolve Trainer candidly shared the hour-long fitness routine of the Friends star, in her interview with Page Six.

“Jen is really consistent in her workouts,” said the director of training.

“[During] my time with her, she wants a hard, challenging workout,” and shared, “We do a lot of core work.”

“We focus really on that total 360 core strength, again, to keep your body upright and moving long term. [There are] some cardiovascular pushes in between and some light plyometric work,” she added.

The workout focuses on “strength and sculpt, sculpt and burn and progressive weight training.”

Meanwhile, the fitness instructor explained “The formats in our workouts are kind of a hybrid of all of our signature formats.”

“Then we do a little weight lifting, as well, to help her build muscle mass and bone density, and with really a focus on longevity in her body.”

She went on to say, “Towards the end of it, always a nice little cool down.”

However, in the next session they used Aniston’s favourites the “P.band” and shared, “Sometimes we’ll use a foam roller or our massage balls, [and] that P. ball to do a little myofascial release.”

“They always say, ‘Break a sweat, not your body,” she continued.

“She comes in, and we kind of get right to work. She sets her phone aside, and it’s really just about her in the moments we’re working together,” she concluded by saying.