The 25-minute-workout Rihanna swears by

If you’re wondering how she keeps fit given her celebrity (read: crazy busy) schedule, you’re not the only one.  UK Grazia magazine got Rihanna’s personal trainer and dietician, Harley Pasternak to spill the (mung) beans on the star’s exercise regime.

“I've put her on a special 25-minute-day work-out that consists of five mini workouts,” Pasternak told the magazine.

“She does it five days a week, wherever she is in the world... it's easy for her to fit around her busy schedule and even her holidays.”

Easy? Well, we wouldn’t call the example routine Pasternak gave easy. Five minutes straight of squats?! But saying that, it is pretty straight-forward and doesn’t require any fancy equipment. Check it out:

Five minute cardio warm-up, eg jogging
Five minute upper body workout, eg push ups
Five minute lower body workout, eg squats
Five minute ab workout, eg sit ups
Five minute cardio cool-down, eg skipping

Pasternak’s other top piece of advice is also surprisingly simple: wear a pedometer to make sure you’re walking enough each day.

“I tell her (Rihanna) to make sure she takes 10,000 steps a day.”

So, let’s get this straight, Pasternak: by taking 10,000 steps a day and doing one 25 minute work-out, we could have a body like Rihanna?

We could be persuaded to give it a try.

Let us know if you try Rihanna’s work--out by leaving a comment below, or on Facebook or Twitter.

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