P90X2 - Chest + Back + Balance(2013)

The same mega pump that was P90X Chest and Back now gets an added benefit, an array of unstable platforms designed to make your body earn its muscle. As you improve at this workout, your strength gains will be superior to those made with any traditional weight-training workout. Work out from unstable platforms and gain strength and balance at a rate that can't be matched by traditional weight training.

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