This Fly Girl is all woman! Jennifer Lopez is proof-positive that age is just a number. At 45, the "Booty" singer looks and feels better than she ever has — and it shows. Flaunting her fab figure in a series of sexy swimsuits during a photo shoot for the cover of Us Weekly's "Best Bodies" Issue, Lopez practically oozed confidence and sex appeal.

"I embrace who I am," the American Idol judge told Us between setups. "I feel sexy, I feel youthful, I feel pretty sometimes."

On days when she feels "not pretty," she looks inward, not outward. "I think a healthy body image comes from being the best you, not competing with anybody else," she explained. "You know, I'm not a 6-foot tall model...I'm not a size 2. I think it's about focusing on yourself and just trying to be the best you."

Lopez is focusing on herself in other ways, too. Single since splitting from longtime love Casper Smart in June 2014, the Boy Next Door actress is enjoying life on her own.

"Being single's good," she teased, laughing. "You have really nobody to answer to, so you can do whatever you want! But I don't think I go wild or anything."

Indeed, when the busy multi-hyphenate does have free time, she's likely spending it with her two kids, twins Max and Emme, 7. Otherwise, she's hard at work on her music, her movie career, her American Idol gig, or her new lifestyle venture, BodyLab. She recently kicked off a BodyLab "Be the Girl" challenge to help women reach their health and fitness goals — and almost 100,000 people have signed up.

"I live a healthy lifestyle, I try to live a healthy lifestyle," she told Us. "I'm always looking for something that's gonna help me enhance that lifestyle. BodyLab is a set of supplements that is about your body working as hard as you do."

Watch the video above to see outtakes from Lopez's cover shoot! And for more from the singer-actress — plus pages and pages of other sexy stars — pick up the "Best Bodies" issue of Us Weekly, on stands now!

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