Movement analysis

Levers

A lever is made up of three basic parts. These are the fulcrum, an effort (also called the load). The fulcrum is the pivot point of a lever, the effort is the force that is applied to one part of the lever and the resistance is at the other end working against the force and effort.

First class lever

It has the falcrum lyling between the effort and the resistance. An example of a first class lever in the human body is the triceps muscle of the arm acts during extension. In this first class level system, the elbow is the falcrum and the hand is the load is the load. The effort is applied by the triceps muscle to move the resistance int the hand.

Second class lever

In the human body, an example would be the ankle joint.The fulcrum being the is the ball of the foot, with the effort of the gastrocnemius muscle. The resistance then would be the weight of the person. The final class of levers is the third class lever. In this kind of lever system, the fulcrum is located at one end and the resistance is at one end and the resistance is at the other end of the lever. The effort is located between the fulcrum and the resistance.

Third class lever

The majority of the body's joints act as third class levers: for example, the biceps acting at the elbow to cause flexion acts as a third class lever system.

Mechanical advantage

Different types of levers have different types of mechanical advantage in how they work. The mechanical advantage of different levers depends on the distance between the effort and the fulcrum when compared to the distance of the resistance from the fulcrum. These differences are known as the effort arm and resistance arm respectively.

Movement analysis

When movements occur in the sagittal plane and around a transverse axis, the movements are called flexion and extension. At the shoulder, flexion involves moving the whole arm forwards. The main agonist causing flexion at the shoulder is the deltoid. Extension at the shoulder involves moving the whole arm backwards. The main agonist extension at the shoulder is the latissimus dorsi. Shoulder flexion occurs during backstroke swimming and when serving at badminton. The action of the upper arm during sprinting also involves flexion (and extension) at the shoulder.

Muscle action

Muscles can only contract and pull. Therefore, joints have to have two or more muscles working opposite each other, one to pull the bones in the opposite direction. As one muscle contracts, the second muscle relaxes.

Muscular System

The muscular system is also responsible for all the movement that occurs throughout the man body. Muscles are attached to the 700 human bones in the skeletal system. Overall there are 639 skeletal muscles in the human body. The muscular system is an organ system that consists of skeletal, smooth and cardiac muscles. Some muscles are known as discrete organs such as blood vessels, tendons and nerves. There are also three types of muscle tissue Visceral, Cardiac and Skeletal.

Visceral muscles are found in organs like the stomach, Intestines and Blood Vessels.

Cardiac muscles are only found in one place, The Heart. Cardiac muscles are responsible for pumping blood throughout the body. The muscle tissue for these muscles can't be controlled consistently, this means that they are involuntary muscles. Cardiac muscle stimulates itself to contract.