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).
Training To Maximize Your Muscle Fiber Types! 1  If you can do only 4 to 7 reps with 80% of your 1 RM, you have mostly fast twitch fibers in that muscle. The reason you will only be able to do 4 to 7 reps with 80% of your 1 RM is that fast twitch muscle fibers are strong but don't have great endurance.