Normal levels of creatinine in the blood are approximately 0.6 to 1.2 milligrams (mg) per deciliter (dL) in adult males and 0.5 to 1.1 milligrams per deciliter in adult females. Muscular young or middle-aged adults may have more creatinine in their blood than the norm for the general population.
Fiber Types and Skeletal Muscle Hypertrophy The force generated by a muscle is dependent on its size and the muscle fiber type composition. Skeletal muscle fibers are classified into two major categories; slow-twitch (Type 1) and fast-twitch fibers (Type II).
Muscle Fiber Types. Skeletal muscle fibers have metabolic and mechanical differences that allow them to be classified into different types. A motor unit, which consists of a somatic efferent neuron and all the muscle fibers it innervates, is comprised of muscle fibers that are all of the same type.hus the classification for muscle fibers also applies for motor units. Some of the different characteristics of muscle fiber (and motor unit) types are listed in the table. These are grouped in colors according to four basic features about muscle fibers.