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.
Types of muscle fibers. Skeletal muscle, the type that is responsible for moving our muscles when we run, is comprised of three different muscle fiber types, each with its own advantages, disadvantages, and specialty.
Characteristics of muscle fibre types. As we know there are three types of skeletal muscle fibre and they each have different capacities to produce force, different fatigue rates and rely on different energy systems in order to function. The reason for these differences is due to their individual characteristics.