The shape of normal stool is mostly cylindrical, long, soft and yellow, moderate thickness, but it varies from person to person without too much standard. Normal human bowel movement and the usual diet has a lot to do with, if you usually eat food with a lot of pigment, such as red dragon fruit, Oreo, etc. The discharge of the stool may be red, black, but it is also a normal stool, and can not be based on the stool must be yellow standard to determine. Some people who love sports, gastrointestinal activity is more active compared to those who do not love sports, their gastrointestinal peristalsis will be faster, discharged stool may be softer, and even will not form a cylindrical shape; and do not love sports people, defecation may be relatively dry, but also are normal stools. So the shape and standard of the stool is just for most people, there is no strict sense of the standard, but if suddenly the usual habits of defecation, a sudden change in the nature of the stool, and there is no other factors affecting, then you need to be vigilant is not the intestinal tract disease, it is best to need to go to the hospital for examination.