ab exercises that wont hurt my back?

Question by : ab exercises that wont hurt my back?
i used to do my ab workouts on my carpet or at a mat at cheer practice.
i live in a dorm now, we have a carpet but its not very comfortable. it doesnt hurt to do crunches, but i feel like crunches dont do anything and would much rater do full situps, but it hurts my back on the crappy carpet.

are there any other ab exercises that might not hurt my back as much?

Best answer:

Answer by Hgygn
http://www.youtube.com/user/sixpackshortcuts

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