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says trainer Adam Ernster who helped the triple threat prepare for the role.

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“With all my clients, it’s pretty much a full-body workout,” says Ernster.

I’m not a proponent of core workouts.

“I figured I better make it worth it for her!”

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“Time is always an issue,” he adds.

“You don’t have to be a billionaire or a rock star.

If you’re a young mother, it’s an issue.

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So the key really is just to get 20 minutes.

Keep your chest lifted, abs engaged and weight pressed in your front heel.

Hold for 30 seconds.

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Hold for another 30 seconds.

Rest for 10 seconds.

Do as many reps as you’re able to in 30 seconds.

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If you have a rug, use it to help increase your resistance.

Crawl for 30 seconds.

Rest for 10 seconds.

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Your arms are out to the side at shoulder height on the floor.

Press your heels to the sky (bottom), engaging your core muscles on the ascent and descent.

Continue, doing as many reps as you could, for 30 seconds.

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Rest for 10 seconds.

Rest for 10 seconds.

Repeat this entire series 3 times.

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Get SELF on youriPadandKindle Fire!

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