Stability balls AND Bosu balls are great for situps...and pushups for that matter!
You guys should do this... I've been secretly doing this for four weeks. http://www.hundredpushups.com/ I couldn't do five when I started... I'm at about 40 right now.
Me-46, D-21, S15, S13
After many years w/my head in the sand... I FILED Divorced 6/2011
The average woman would rather have beauty than brains, because the average man can see better than he can think.