The Latino singer, who gave birth to twins Max and Emme in February, is reportedly losing up to 10lbs a week by getting up at 4am and hitting the gym in a bid to regain her famous figure.
A source told Britain's Closer magazine: "Jennifer has always been a workaholic and she has applied the same attitude to her post-pregnancy regime. Because raising twins is so demanding, she gets up at 4am to fit it all in.
"She spent the last month of her pregnancy planning her regime with a team of nutritionists and personal trainers. She calls them her 120lb team in reference to her target weight. She is working out for three hours a day, seven days a week."