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Selena Gomez has been working out with the trainer Amy Rosoff Davis – who has not only been looking after the singer's fitness but also her diet and lifestyle – for about a year.

Since starting last spring, the singer has worked out with Rosoff Davis anywhere from three to five days a week, and in the last couple of months before the start of the Revival tour, they were exercising seven days a week for up to two hours at a time — on top of which Gomez was doing back-to-back run-throughs of her 90-minute show.

Here, the trainer has spilled all the secrets on how Gomez got the body she has now.