Singer Ciara appears on this month's cover of Shape magazine looking super fit.

But the 29-year-old wasn't always so in shape.

During her pregnancy last year, the "Goodies" singer gained 60 pounds.

"When I was pregnant with [son] Future, one thing I learned quickly was, don't ever let a pregnant lady be hungry, because when I was, I was like the Tasmanian Devil!" she tells Shape magazine. "I indulged in all the good food the world has to offer. After he was born — when I couldn't exercise yet — I kept eating, and I gained 60 pounds."

"But as soon as the doctor said I could start training again, I was on the treadmill the very next day," Ciara told the magazine in her cover story. "Once I got back into it, I worked out two or three times daily. I would go to [trainer] Gunnar Peterson first for my one-hour training session, then I'd have two more cardio sessions later in the day."

"That, along with a really clean eating plan, was how I lost 60 pounds in four months. It was a very intense program, and I was extremely focused on it."

During her intense workouts with a trainer, Ciara especially enjoyed "an hour-long plyometric cardio circuit that always includes boxing elements."

But the singer says her diet was just as important as her workout regimen — especially one thing in particular — water.

I believe that drinking tons of water and flushing out your system is crucial for training. It really helped me drop the weight. I tell myself that water is my medicine and that to stay well, I have to drink a gallon of it every day. 

And while Ciara says she also put herself "on a strict eating regimen," she does admit to needing cheat days.

"I give myself a break," Ciara tells Shape. "At some point I have to have French fries, a cheeseburger, and some pizza. And Oreos and vanilla ice cream!"

Ciara's hard work has paid off.

In the year since she gave birth, Ciara released her sixth studio album, starred on the NBC reality competition series "I Can Do That," and went on tour.

She also started dating Seattle Seahawks quarterback Russell Wilson, and documenting their fabulous life on Instagram:

SEE ALSO: How 20-year-old Gigi Hadid became the world's hottest fashion model

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