I would go with the 12 week off season intermediate program. I've done it the past two years. The best part about going one step above what you think you are capable of doing is that you push yourself. You can also deviate from the program if you want as well.

I'm currently doing the advanced program and I make changes as time permits and depending on how I'm feeling. One thing for sure you will have a stronger core after completing this. Say goodbye to the mashmellow core.

Best of luck.
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Cyclysm