These close grip pull downs can be done as part of a strength training circuit to help you tone your entire back and especially your lateral muscles. The close grip pull down also employs your midsection (this is where most of your power will come from), so you'll also get a nice little surprise when you look in the mirror at your ab region in a few weeks.
To learn how to do the close grip pull down, check out this finess video. Practice this exercise a few times a week to see results quickly.
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