I heard from some1 that too much core can throw off your balance rather than help it and it should not be done more than 5 times a week. Does anyone here do a large amount of core work 6-7 days a week? If so, do you think there would be any differnence in running if you took the intensity of it down a notch and did it less? Also, how much does core work help running? Say if you do it 2-3x per week, is there any difference for running doing it more or less???
It depends on what type of abdominal work you are doing. In a well-devised routine, you can do core 6-7 days per week at an intense level so long as each day is working different muscles (you have 8 abdominal muscles + obliques, etc).
I don't see how a strong core could ever be a detrimant. If you don't do core at the collegiate level then you're basically a step behind everyone else.
I've done a couple years of 6 days/week, 3 of which were 45-60 min core sessions. Absolutely no detriment. I felt very strong and have never had a side stitch since.
The word excessive means too much. So yes, excessive core is bad.
Glad someone asked.
Teachers of chi gong, Feldenkrais, or Alexander Technique will all tell you that most (frontal) core work is "too much," because it tenses the front of your body and causes you to hunch forward. If you've ever been to yoga class, recall how you are encouraged to roll on your side to get up off the floor, rather than to do a big sit up.
So, what supports your back? My Alexander Technique teacher says: "your back." He's 80, and looks very good - stands and walks erect, and is in excellent health.
Keep in mind, all these modalities are focused on long term health - into old age - rather than on running your fastest race today.