When I first heard the term "power 90x" floating around, I was unsure if it was a new porn site or the long lost brother of C-3PO.
The power 90x workout program is designed to work using "muscle confusion," aka high-intensity cross-training. The thought is that by working out different muscle groups every day, you avoid plateaus and get better results. The nutrition plan is a huge part of it too though.
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