Credit: @MariahCarey

Motherhood has made Mimi buff!

Three months after giving birth to twins, Mariah Carey hit the beach in a one-piece -- and proudly showed off her post baby bod to fans in a TwitPic posted on Tuesday.

"Ocean work out! It's been a loooong time since I've been in the ocean," wrote the Grammy winner, 41. In the pic, Carey triumphantly beams and stretches out her toned arms and shoulders in a cleavage-bearing one-piece swimsuit, sunglasses and sun visors.

"My body went through so much," Carey recently admitted of her pregnancy with son Moroccan and daughter Monroe, born April 30. (The twins' dad is her hubby Nick Cannon.)

"I was so uncomfortable," added Carey. "I'm kind of proud of myself. I really am -- sorry, pregnant with twins is different than anything! [People] were always saying to me, 'Oh, but it's all worth it!' Yeah, but it's easy to say when you're not the one whose feet are this big! It turned into like a really difficult time."