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).
Slow-twitch muscle fibers are slower to contract, but they take a long time to fatigue. This makes them ideal for endurance work. In fact, they play a role in many of our activities of daily living, such as walking, housecleaning and maintenance of your posture.