How Rihanna Got in Navy-Ready Shape for Battleship

by Alanna Nuñez for SHAPE.com

RihannaRihannaAre you tough enough to serve in the military? To get in fighting shape for summer blockbuster hit Battleship, superstar singer Rihanna had to be! While on set, she worked with a nutritionst, a personal trainer , and former Navy officer Jacqueline Carrizosa in order to realistically portray Petty Officer Cora Raikes. We managed to snag a few minues with Carrizosa, and she gave us the workout moves she used to help whip Rihanna into shape.

Carrizosa wasn't in charge of Rihanna's day-to-day workouts-the singer also had a personal trainer and nutritionist on set-but she did act as a consultant since she's served in the military.

"We did the basics like push-ups, pull-ups, and crunches," she says. "Those moves are good for anyone, even if you don't have a lot of time to get in shape."

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But the real move that Carrizosa swears by? Military 8 counts! Also known as the 8 count body builder pushup, this eight-movement mix of a push-up and a burpee is hardcore. Want to give it a shot? Here's how to do it:

1. Start in standing position.

2. Drop down to a squat.

3. Thrust your legs back so that you're in a push-up position.

4. Complete one pushup and push yourself back up.

5. Spread your legs hip-width apart.

6. Jump your legs together so that you're back in a push-up position.

7. Jump back into a squat position.

8. Stand back up. That's one rep.

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What do you think? Are you a fan of the military 8-count move? Tell us what you think in the comments below, and be sure to check out Battleship out now on Blu-Ray and DVD !

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