Originally Posted by datlas

Here is what I do. It works very well for me in preventing back pain which I used to get on rides longer than say 2 hours, but now no back pain unless I do something crazy like a century:

1. Front plank (support body on forearms and ball of feet, body should be all in one plane/straight) - hold for 1-2 minutes, 3 sets

2. Side plank (like 1 but on your side, one arm over your head), each side hold for 1-2 minutes, 3 sets

3. flying superman (like on floor, keep legs straight with arms in front, raise legs off floor and raise arms/head/chest, your lower ribcage, abdomen and upper thighs are on the floor, rest in the air)- hold for 30 seconds, 4 sets

4. Reverse crunches - lie on back with bent knees, raise feet off floor - do as many as you want (start with 10 and increase as tolerated)

For the first 3, if you are out of shape you may wish to do them just for 10 or 15 seconds, gradually increase.

I do these maybe 2-3 times/week, it only takes 15 minutes and you can do it while watching TV etc.