To take a bad fall, similar to the terms "eat snow" in snow skiing and "eat dirt" in biking. Eat shit can conveniently be used to describe a fall on any kind of terrain, including gravel, concrete, snow, ice, water, or anything you can think of. It is a commonly used term in waterskiing.
Dude... I'm a great waterskiier, but I always eat shit coming around that damn turn!