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.
Blood in Stool: Breast fed babies can have mucosy, seedy stools; it is normal. Blood in the stool needs confirmation. Swallowed blood from breast can cause darker bloody stools. Baby's stool needs to be tested- hemoccult test to see whether it is blood.