1. BALANCE & STABILITY

2. Balance & Stability Balance: The ability of the body or an object to maintain equilibrium (no change of speed or direction) Stability: The ability of a body to resist a change in equilibrium.

3. Types of Stability Static stability When an object is at rest, a set position has to be maintained for a set time Archery Dynamic stability When an object is moving, it can be easily altered. Dodging in netball

4. Factors that Affect Balance & Stability Mass of the object (weight) Area of the object’s base of support Height of the centre of gravity above the base of support Position of the line of gravity

5. Mass of the Object The greater the mass, the greater the stability eg sumo wrestler

6. Area of the Object’s Base of Support It is the area that is bound by the body parts in contact with a surface (eg: ground) The greater the base of support, the greater the stability.

7. Centre of Gravity Gravity is the force that acts upon the human body in a downwards direction, pulling downwards towards the centre of the earth The centre of an object’s mass is known as the Centre of Gravity The centre of gravity of a human changes with movement and can even lie outside the body The closer the centre of gravity to the base of support, the increase in stability

9. Line of Gravity The line of gravity is an imaginary line passing downwards through the centre of gravity to the base of support The closer the position of the centre of gravity to being directly over the middle of the base of support, the greater the stability Athletes deliberately position the line of gravity close to the limits of their base of support so that only a small force is needed to move them Swimmers and runners on the blocks