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.
Anal Tears (Fissures): Often, small tears in the lining of the anus can cause blood in the babyâs stool. The anal tissues are extremely delicate, especially in the case of a baby, and contain many small blood vessels. Sometimes, passing a hard stool could cause these tissues to tear, leading to blood in the stool.