At some point, even good girls feel like a little trampoline.

Forget Valentine's Day; if your relationship with exercise doesn't feel like it's "working out," it's probably time to for you to bounce.

Besides, jumping around can be much more beneficial than you thought. Rebounding, which consists of jumping on a mini trampoline (also called a rebounder), was found in a NASA study to be 68% more oxygen-efficient than other forms of exercise, including running (in other words, you can burn 68% more without losing your breath).

If you're afraid of getting hurt, don't worry. Rebounding has zero impact, which means it's gentle and safe, while still giving you the high-impact results your "ex"-ercise couldn't (on top of the increased burn, it's believed to reduce stress, relieve PMS and boost immunity, digestion and circulation).

Ready to love again? Urban Rebounding offers classes in select gyms, or you can even try it at home.