How do you get bulky heavy weights or lighter weights?

Muscular size is not just a matter of how you train. It also critically includes your genetic endowment, diet, and rest and recovery. When training, use the heaviest possible weights without losing perfect exercise technique for the greatest muscular size. Think of the difference in response to, for example, curling a pencil 1000 times and curling a 40 lbs. dumbbell 10 times. The former won't do anything for the size of your biceps, whereas the latter may.

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