“I usually don’t like using percentages for exercises because each muscle group has a different fiber type distribution. For example, the quads (primarily Type IIa) respond differently to a specific intensity prescription than the hamstrings (Type IIb). An athlete who uses 90 percent of their 1RM in the leg press might perform 20 reps in a set, whereas the same athlete may be able to perform only 5 reps with that same percentage when performing a leg curl. (Incidentally, a great reference on the subject of muscle fiber types is La Forza Muscolare by Carmelo Bosco, PhD.)….”
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