Britney Spears isn't the only star who's been showing off her toned figure.
Jennifer Lopez is the cover star of Self's January 2015 issue and just like Britney, the 45-year-old singer has never looked better.
Maybe her workout-inspired photoshoot has got something to do with her new project next year. As well as continuing her role as a judge on American Idol and filming new police drama Shades of Blue, J-Lo is also teaming up with health and fitness company BodyLab to create a new programme for women, complete with recipes, health tips and calorie and exercise trackers.
Speaking about why she chose the role, Lopez says, "I've been through divorce. I've been cheated on, just like every other girl in the world. So you sympathise, you understand the emotions. And I've dated a younger guy once in my life, so I could definitely understand that part, too - the attraction."
It sounds like we're going to be seeing a lot more of Jennifer in the next 12 months.
Read more from her Self interview here and see her incredible style evolution below: