There are some very handy tips below that may help you out in this area...
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help me im all boobies an no BOOTY by: Anonymous
i would really like some tips to make my booty nice and round
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Recommendations... by: The Middle Manager
That is an interesting question. First, let me say that genetics plays an important role in the shape of our bodies.
That said, there are some things you can do to enhance your shape.
Squats, lunges, and leg curls will all target the buttocks. Doing 3 to 5 sets of 6 to 12 reps is optimal for muscle growth.
In addition to lifting weights, do not overlook the importance of nutrition and rest in building muscle. Take a look at this article on building muscle fast for some tips on nutrition, lifting weights and rest.