Muscles, tendons and ligaments How they work together to help us move

Muscle Pairings Muscles work together in pairs and use a pulling force with the bones in the body to move. Muscles pull by flexing/contracting or shortening (going thicker) while the other muscle must extend/straightens or lengthen (goes long and thin). Such muscle pairs are called antagonistic. This means they do the opposite of one another.

Muscle examples Biceps and triceps – raise and lower the arm Pectoral and shoulder – move the whole arm back and forwards

More muscles Quadriceps (thigh) and Hamstring – Bend and straighten the knee joint Calf and shin muscles – bend the ankle joint.

Ligaments Ligaments link bones together. Some very common ones that are damaged are the ones surrounding the knee, eg the crutiate and medial ligaments.

Tendons Tendons tie muscle onto bone and allow the muscle to work the bone as a lever. They are very important. Eg Achilles tendon – attaches the calf muscle to the heel bone. Without it, we could not walk.

Joint types The five main types of joints are Hinge – allow movement in one direction only eg knee and elbow Ball and socket – allow circular movement eg hip and shoulder

Pivot joints can allow some movement eg your neck Gliding and sliding joints are many small bones moving over each other eg ankle, wrist Fixed joints don’t move eg skull.