Try this full body cardio blast from PT Nerissa Peach.

Kettlebell mountain climbers

How to:
Get in push-up position with each hand on a kettlebell, feet hip-distance apart. 

Bracing your core and keeping hips down in line with the rest of your body, drive one knee as high as you can in towards your chest.

Return, switch legs and repeat for number of reps.

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