Backless Dress

A toned back can be as sexy as a pair of gams! For each of these exercises, do three sets of 12 to 15 reps. "But If you really want a challenge, time yourself instead," says co-owner Frank Nunez. "Challenge yourself to do as many reps of each exercise as possible in 60 seconds."

Note: Use the rep or timed rule for all of the exercises in this slideshow.

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