Concentric contractions: A concentric contraction is a type of muscle contraction where the length of the muscles shorten while undergoing tension. For example, when you pick up a curl bar and perform a biceps curl, the length of your biceps muscles shorten.
Blood in Baby's Stool. Babies can sometimes have blood in their stool that is caused by food allergies, a small anal tear or fissure, or even a temporary case of lactose intolerance. It might even be a drop of blood that came from a cracked nipple, which the baby then passed through his system.
Intestinal Causes of Blood in Stools. Amoebic dysentery or commonly know as food poisoning, can also lead to blood in stools. Other condition called as ulcerative colitis, also leads to bleeding. It can be associated with mild to moderate abdominal pain with cramps and with mild fever.