Myoglobin

Myoglobin is a small, oxygen-binding protein found in the heart and skeletal muscles. Its primary role is to store oxygen within muscle cells, providing an immediate oxygen reserve for metabolic activity, particularly during intense muscle contraction. When muscle tissue is damaged, myoglobin is released into the bloodstream. Because of its relatively small size, it typically rises in the blood rapidly after muscle injury and is cleared by the kidneys relatively quickly, making it a useful early indicator of muscle damage.