1.   Bend your knees and use your thigh muscles when picking up heavy objects.

2.   Bend your knees, but keep your back straight.

3.   Lie flat, bend the knees then straighten the legs upwards so that they are at right angles to your body.

4.   Lying flat on your back, bend the knees, then raise the legs.

5.   Red bends her knees and pushes off, pretending to take a shot.

6.   Start as before, first bending the knees, then straightening the legs.

7.   Still lying down, bend the knees and raise the legs.

8.   The trick is to bend your knees as you catch the ball.

9.   To avoid back problems, always bend your knees when you lift heavy objects.

10.   Keep your knees bent and lean forward slightly.