Nephritis is the most common cause of blood in the urine of children and young adults but it can occur at any age. If your GP suspects nephritis he will usually refer you to a nephrologist (kidney doctor).
Muscle fiber types can be broken down into two main types: slow twitch (Type I) muscle fibers and fast twitch (Type II) muscle fibers. These fast twitch fibers can be further categorized into Type IIa and Type IIb fibers, which are also known as fast twitch oxidative and fast twitch glycolytic, respectively.
A rapid or fast-twitch muscle in which pale, large white fibers predominate; mitochondria and myoglobin are relatively sparse compared with red muscle; involved in phasic contraction. categories of muscle fibre adapted for various modes of use.Normally taken to refer to skeletal muscle unless specified otherwise.wo of the three types of skeletal muscle are pale in color and fast-twitchâtype IIa (fast-twitch oxidative-glycolytic), type IIb (fast-twitch glycolytic).