I'm lucky enough to have my piriformis muscle (it connects the hamstring, hip, and your ITB (that runs down the side of the quad) wrap around my sciatic nerve. So, if the piriformis muscle goes into spasm, I'm a cripple for a few days.
Strengthening other muscles around the site (and increasing my hip / hamstring mobility) is key to ensuring that my piriformis doesn't go into spasm and cause me a great deal of agony. :D
The diet isn't the struggle, eating so much salad is my biggest struggle at the moment!
Training days = salad + lean meat for dinner - not the best for our winter that we're currently enduring here in Australia!