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 rugby player with strong leg muscles is taking a kick. Photo Credit Digital Vision./Photodisc/Getty Images. Your skeletal muscle contains two types of muscle fibers: fast-twitch and slow-twitch. Your fast-twitch and slow-twitch muscle fibers are separated into three distinct types.Slow-twitch fibers contain type 1 muscle fibers, while your fast twitch fibers contain both type 2a and type 2b.The percentage of each muscle fiber differs among everyone, and from one muscle to another in the same individuals, according to Fitness: The Complete Guide, by International Sports Sciences Association. rugby player with strong leg muscles is taking a kick. Photo Credit Digital Vision./Photodisc/Getty Images. Your skeletal muscle contains two types of muscle fibers: fast-twitch and slow-twitch. Your fast-twitch and slow-twitch muscle fibers are separated into three distinct types.