Creatine kinase, 310 U/L, is abnormal, and above normal values, certain cardiac or skeletal muscle diseases may be present. Creatine kinase, also known as creatine phosphokinase, is mainly found in the cytoplasm and mitochondria of cells, and is most abundant in skeletal and cardiac muscle, and is an important indicator for detecting cardiac and skeletal muscle diseases, with normal values ranging from 38 to 174 U/L in men and 26 to 140 U/L in women. Creatine kinase levels are affected by factors such as gender, age, and physiological status. Men have a greater proportion of skeletal muscle than women, so men’s creatine kinase levels are higher than those of women. When the heart or skeletal muscle is damaged, e.g., heart attack, trauma, etc., the heart muscle and skeletal muscle cells break down, and the creatine kinase in the cells is released into the bloodstream, causing the creatine kinase level to rise. However, only one test value of creatine kinase alone does not confirm the various diseases, and other tests are needed to confirm the diagnosis.