The songstress gave birth to her first child, Axl, less than three months ago (29 August) and is already working on her post pregnancy figure, as she took to the hilly terrain of Mandeville Canyon Park in her hometown for a bit of cardio.
And although she was working out, Fergie still managed to stay true to her rock chick image!
She paid homage to heavy metal band, Motley Crue, by donning a statement T-shirt and teamed her rockstar top with some black leggings and a silver studded bum bag.
Fergie also slung a pair of headphones around her neck and wore a pair of sunglasses to shield her eyes from the bright LA rays.
Despite being a busy mum-of-one, the Black Eyed Peas singer has still been seen out and about socialising with her pals (including Kim and Khloe Kardashian!) and celebrating her sister Dana's pregnancy at a baby shower last week.
And each time she has looked fab, wearing outfits that flatter her figure.
Clearly though, Fergie is a mum on a mission to get back to the body shape she was before having Axl and judging from these snaps, she's not wasting any time!
Her husband Josh Duhamel has been revelling in his new parenting responsibilities too and last Thursday (14 November), Fergie made sure that he was given a birthday message to remember by posting an adorable photo of Axl on Twitter, along with the caption: "HAPPY BIRTHDAY DADDY!!!! @joshduhamel."
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