Teenage bodybuilding

Bodybuilding have many competition categories for young entrants. Many current professional bodybuilders started weight training during their teenage years. Bodybuilders such as Lee Priest and Jay Cutler all started competing when they were teenagers. Today many teenagers compete in bodybuilding competitions.

Professional bodybuilding

Professional bodybuilding called also pro bodybuilding. It is a term that is used in the sport of bodybuilding, and may refer to several different concepts.

In the modern bodybuilding industry "Professional" generally means a bodybuilder who has won qualifying completions as an amateur and has earned a 'pro card' from the IFBB. Professionals earn the right to compete in sanctioned competitions including the Arnold Classic and the Night of Champions. Placings at such competitions in turn earn them the right to compete at the Mr. Olympia; the title is considered to be the highest accolade in the professional bodybuilding field.
Many natural bodybuilding organizations such as the Natural Physique Association and North American Natural Bodybuilding Federation also have professional ranks.

Muscle

Muscle is contractile tissue of the body and is derived from the mesodermal layer of embryonic germ cells. It is classified as skeletal, cardiac, or smooth muscle, and its function is to produce force and cause motion, either locomotion or movement within internal organs. Much of muscle contraction occurs without conscious thought and is necessary for survival, like the contraction of the heart, or peristalsis (which pushes food through the digestive system).
Voluntary muscle contraction is used to move the body, and can be finely controlled, like movements of the eye, or gross movements like the quadriceps muscle of the thigh. There are two broad types of voluntary muscle fibers, slow twitch and fast twitch. Slow twitch fibers contract for long periods of time but with little force while fast twitch fibers contract quickly and powerfully but fatigue very rapidly. The Muscles are the most important part in Bodybuilding.