After 2 minutes your muscles have recoverd as much as they are going to. so waiting longer really only has a mental and cardio vascular benifits. I try not to time how long I take between sets, Instead I look at the overall picture. If I have 4 movements, and an hour to do them ... i time accordingly. But I almost never go over an hour.

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I don't do this for my family, my friends, women, accolades, pride, or ego. I do it for me and no one else, its just part of who I am.