Sitting for a period of time lumbago can have the following causes: first, lumbar dorsal muscle fasciitis, lumbar dorsal muscle fasciitis is often caused by cold, strain, which can appear after sitting for a long time lumbago, this time to early examination and examination to exclude other diseases to diagnose. Second, lumbar muscle strain, lumbar muscle strain is often caused by chronic injury to the muscles of the waist, after sitting for a period of time can appear the symptoms of lumbar muscle pain, then early physical examination for diagnosis, early physical therapy and oral medication. Third, lumbar disc protrusion, lumbar disc protrusion serious can appear after sitting back pain, can be accompanied by hip discomfort and double hip discomfort, then early CT, nuclear magnetic examination of the lumbar disc to early diagnosis and early treatment.