what are muscles made of

Muscle cells contain protein filaments of actin and myosin that slide past one another producing a contraction that changes both the length and the shape of the cells. And their main function is to produce power and motion.The term muscle is derived from the Latin musculus meaning "little mouse" perhaps because of the shape of certain muscles or because contracting muscles look like mice moving under the skin.Muscles are predominantly powered by the oxidation of fats and carbohydrates, but anaerobic chemical reactions are also used, particularly by fast twitch fibers. These chemical reactions produce adenosine triphosphate (ATP) molecules which are used to power the movement of the myosin heads.

• There are three types of  muscles:

1. Skeletal or striated: they react when they are commanded by the brain to do a certain action: and skeletal muscles can be divided into two groups, slow twitch and fast twitch fibers.An average adult male is made up of 42% of skeletal muscle and an average adult female is made up of 36%.
2. Smooth muscles: they contract without conscious thought and are termed involuntary.They are  found within the walls of organs and structures such as the esophagus, bronchi, intestines, stomach,uterus, urethra, blood vessels,bladder, and thearrector pili in the skin (in which it controls erection of body hair). 
3. Cardiac muscle (myocardium), is also an "involuntary muscle" but is more akin in structure to skeletal muscle, and is found only in the heart.

• Fast twitch muscle fast twitch muscle, has three major subtypes (IIa, IIx, and IIb) that vary in both contractile speed and force generated. Fast twitch fibers contract quickly and powerfully but fatigue very rapidly, sustaining only short, anaerobic bursts of activity before muscle contraction becomes painful. They contribute most to muscle strength and have greater potential for increase in mass. Type IIb is anaerobic, glycolytic, "white" muscle that is least dense in mitochondria and myoglobin. In small animals this is the major fast muscle type, explaining the pale color of their flesh. So if you are heading to make muscle mass you will be using this fast twitch muscle and you aren't going to be able to do a big number of repetitions.

• slow twitch, or "red" muscle, is dense with capillaries and is rich in mitochondria and myoglobin, giving the muscle tissue its characteristic red color. It can carry more oxygen and sustain aerobic activity using fats or carbohydrates as fuel.Slow twitch fibers contract for long periods of time but with little force.  people use this muscle when they are lifting a light weight and doing a lot of repetitions. If you want to get your body in shape then this is the muscle you will use.