Personally I've always gotten the best results growth wise lifting heavier. I would never discount that everyone is different, however. While this is a bodybuilding site the majority of us never have any intention of stepping on a stage. Like hrdgain said, some of us don't want to work our ass off in the gym and then throw out our backs moving furniture around. There is for some also a general sense of "fitness".
What applies to the elite bodybuilder with genetics and gear on his side doesn't apply to everyone. There are other ways to get big and the look that some people want to achieve may be different than what you want to achieve. The idea that we should never talk about reps outside the 8 to 12 range is ridiculous. You can be a bodybuilder and not want to be a big weak water weenie
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