3 Functions of the SkeletonMovementBones meet to form JOINTS. Tendons attach muscles (which cause the movement) to bones.

SupportWe are able to stand and form other complex positions. The skeleton gives a framework and affects size/body composition.

ProtectionVital organs are protected e.g. cranium (brain), ribs (heart/lungs). Petr Cech would’ve suffered a severe brain injury if it wasn’t for his skull!

Cartilage reduces friction between bones (and is elastic)Joint Capsule is tough and produces synovial fluidSynovial fluid lubricates the jointLigament attaches bone to bones

Joints and Movement

Examples from SportThink of how the 3 functions work together in:Rugby, DivingCricket, DanceNetball, SwimmingHockey, Basketball

Joints allow movement to occur (with the help of muscles).In the upper body they allow mobility and the lower body are mainly for stability.

MovementElbow

Hinge JointHumerus, Radius, UlnaFlexion (bending)Extension (straightening)

Knee

Hinge JointFemur and Tibia ONLYFlexion (bending)Extension (straightening)

Shoulder

Ball and Socket JointHumerus and ScapulaFlexion (bending)Extension (straightening)Abduction (away)Adduction (adding)Rotation (around)

Hip

Ball and Socket JointPelvis and FemurFlexion (bending)Extension (straightening)Abduction (away)Adduction (adding)Rotation (around)

Exercise and the Skeletal System

Bones become lighter with age and their density and strength reduces. If too much bone is lost, then the bones can break easily – OSTEOPOROSIS (think of a crumbly Cadbury’s Crunchie!)

Importance of Weight-Bearing Exercise

Bones continue to grow until we are 18. Regular exercise helps to develop bone structure.

Exercise helps by:

1. Increasing bone density2.Tendons and ligaments become thicker, increasing flexibility and power

BUT….TOO MUCH EXERCISE CAN BE HARMFUL!

Recommended ExercisesWeight-Bearing exercisese.g. walking, running, tennis, aerobics as they put weight and pressure on bones, increasing their strength.

Non Weight-Bearing exercisese.g. swimming, cycling, yoga

Injuries and Treatment

INJURIES TO BONESFractures: ‘broken or cracked bone’

Closed – ‘does not break skin’Compound – ‘breaks the skin’Stress – ‘overuse injury, fatigue, poor diet’Symptoms: Pain, swelling, inability to move, bruised

INJURIES TO JOINTSTennis/Golfers Elbow – Overuse injury to the tendons. T.E. is pain on outside of the elbow.G.E. is pain on inside of the elbow.Dislocation – bone forced out of normal range of motionSprain – Damaged ligament often from twisting (e.g. ankle, wrist, knee, elbow)Torn cartilage – caused by pivoting, will fall to floor.

TREATMENT FOR INJURIES – R.I.C.E.Rest Ice Compression Elevation

Diet and the Skeletal SystemEating a balanced calcium-rich diet will assist the growth of strong bones. Cheese, milk, yoghurt (but low fat ones!).

Vitamin D helps to maintain healthy bones and aids the absorption of calcium.

Smoking and alcohol have a toxic effect on bones.