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).
The first type of fiber we will look at is the type I, or slow twitch fibers. These fibers are slow to contract (hence, slow twitch), and can sustain muscular contractions for an extended period of time. This factor makes them ideal for endurance type of events where one is exercising for long durations.