1) Lie back onto floor on top of a balance disc with both knees bent and feet flat. Place hands at sides.
2) Contract abdominal muscles continuously to stabilize trunk (or tuck stomach in by drawing naval in towards spine). Lower back should be in a neutral position.
3) Start position: Straighten both legs so that they are perpendicular to floor.
4) Slowly lower one leg to approximately 45°.
5) Return to start position and repeat.
6) Remember to maintain stability in lower back throughout movement by keeping abdominal muscles contracted
