To improve power and strength of the muscles which run at the back of the thigh, from the pelvis to the knee.
Lie on your back on the floor with legs straight. Arms should be slightly out to the side with palms down. Bendboth knees with feet flat on the floor.
Tighten the abdominal muscles. Simultaneously lift your buttocks off the floor by 3-6 inches or so. Hold this position for 3-5 seconds then slowly return to the starting position as you exhale. When you are strong enough do this manoeuvre using one leg whilst you hold the other leg straight off the floor.
It is important to engage your core' abdominal muscles throughout this exercise to support the lower back and stabilise the pelvis.
A similar variation of this exercise can be done using both legs at the same time over a Swiss ball.
The sets and repetitions are to be determined by your osteopath.