To keep fitness fun, you've got to think outside the box-step. Hollywood trainer Jeanette Jenkins has introduced hula-hooping and crumping into her group fitness classes. "It helps you stay creative, and keeps things fresh," she says. Dig up your old toys for an intense Skip-It workout or, dare your friends to show up at the gym in the tackiest apparel they can find. (Think 80s jazzercise spandex or anything Kelly Kapowski wore on "Saved by the Bell".) Aren't you feeling lighter already?

Which blast-from-the-past toy would you want to use in a workout?

• Hula hoop
• Jump rope
• Pogo stick
• Tetherball
• Slip 'n Slide

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