The actress revealed her sizzling bikini body while vacationing in Mexico. Her trainer Ramona Braganza – who last month revealed Alba, 27, had already lost 25 pounds – says the rapid results are the result of consistent workouts since Alba and husband Cash Warren welcomed Honor Marie on June 7.
"She worked out an hour a day, five or six days a week, and stayed on a strict diet of about 1700 calories a day, losing 600 calories because of exercise," says Braganza.
Alba stuck to a low-fat, low-carb diet as part of Braganza's 321 Baby Bulge Be Gone plan.
Alba had said she wanted to take off the weight in a responsible amount of time, but Braganza tells PEOPLE that Alba made "amazing progress in a very short time. She really works at it."
Didn't Feel SexyAlba now may have that post-pregnancy glow, but she revealed in the August U.K. edition of Cosmopolitan that she "never felt less sexy" than when she was expecting, adding, "I mean, I wouldn't have changed it for the world ... but I wanted to get rid of all the weight."
Alba followed Braganza's 12-week plan to the letter and is now adhering to more of her longtime trainer's advice: "Take some time off and enjoy your body. It's good to treat yourself after all that hard work."
But that doesn't mean the actress lolled around and pigged out on vacation. "She loves to move," says Braganza. "She swam and played volleyball, but she was out of the gym and enjoying herself."
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Jessica welcomes her daughter Honor Marie