Whether you’re a skinny guy desperately trying to pack on muscle (like Michael B. Jordan in Creed) or a not-so-skinny guy trying to convert body mass into muscle (like Chris Pratt in Gaurdians of the Galaxy), bulking up the right way is a challenge. But that doesn’t mean it’s complicated (read here for 15 more basic muscle-building facts). With the right training regimens (yes, you want more than one routine on deck), balance of calories and nutrients, and lifestyle you can be on your way to a thicker, stronger you.

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DOWNLOAD The 21-Day Shred app for iOS to get the full training program, diet, and more. No iOS? No problem. Get a COPY of the PDF.