The schemas are a set of 'types', each associated with a set of properties. The types are arranged in a hierarchy.he schemas are a set of 'types', each associated with a set of properties. The types are arranged in a hierarchy.
Inadequate stretching and warming up prior to exercise, or advancing your exercise program too quickly, or beginning a new exercise program, have all been known to cause symptoms. In some people, just vigorous walking or exercising on uneven ground is enough to exacerbate a flare-up of sciatica nerve pain.
When the sciatic nerve is compressed or irritated, it can cause: 1  pain. 2  numbness. 3  a tingling sensation that radiates from your lower back and travels down one of your legs to your foot and toes.  weakness in the calf muscles or the muscles that move the foot and ankle.