Can your abs shrink if they are over worked? I know you can work abs more often then some of the other mucsle groups. I have been working abs daily and have seen some good progress over the last 3 weeks. Or can you even over train your abs? I know alot of people only work them 3 times a week but for me I think im an everday or at least 5 days a week ab guy. I do about 200 reps a day various exercises. When in the gym I use weights for some of my ab work. My diet is in check as well.
I wouldn't think so. It's hard to over work your abs because they are mostly endurance fibers. But then, I only have to work mine when I feel like it. Right now, being pre contest, we hit them about every other day or so. Only two to three sets of 20's.
"When you get to the end of your rope, tie a knot in it and hang on."
It's really hard to overtrain your abs. I have some friends that took or are still taking Brazilian Jujitsu. One of them goes to class seven days per week, and they do very intense ab workouts in that class. I do 6 supersets for my abs 4 times per week (I was doing 3, but I increased it because I wasn't improving) and I think it is working so far.
Most people probably don't need to train their abs more than 2-3 days a week, but I have known plenty of people who train their abs 5-7 days per week with good results. If it works for you then don't worry about it.
The only time it's bad to feel the burn is when you're peeing...
If you are trying to get them stronger (like for Oly-lifting, powerlifting) i would say the more you work abs the better (not tons of volume everyday though, balance is always key). But working them everyday for aesthetic purposes? i wouldn't really recommend it...because of what mudge said.
"The greatest obstacle to knowledge is not ignorance but the illusion of knowledge." -Barry Marshall, Nobel Laureate