The human body is made up of approximately 640 muscles – some are well-known and prominent, others small and buried deep inside the body. Some of the more well-known muscles include the quads, hamstrings, biceps and triceps. What most people don’t realise is that most of these muscles are made up of several individual muscles, working together to perform specific functions.
Muscles of the Leg
The quads, or quadriceps is Latin for four-headed. The quads is made up for four muscles, namely: rectus femoris, vastus lateralis, vastus medialis and vastus intermedius. These are large muscles located at the front of and on top of the thigh bone. On the lower end, the tendons of the four muscles unite and attach to the knee cap, or patella. The main actions of the quadriceps is to straighten the leg at the knee joint and to bend the leg at the hip joint; therefore the muscle plays a vital role in all weight-bearing actions such as walking, running, climbing and jumping.
The hamstrings are another group of muscles that move the leg. They are located at the back of the thigh and are made up of three muscles: semitendinosus, semimembranosus and biceps femoris. A hamstring's main functions are to bend the knee and to extend the leg backwards at the hip joint. Hamstring injuries are very common in sports people and they usually occur when the athletes run and/or kick very hard. The force of the contraction pulls the muscle away from the bone it is attached to, resulting in a temporary disability.