Supine leg swing
1. Lie face up, arms out to the side. Swing your right leg across your body – with your knee as straight as possible.
2. Just before your foot reaches the floor, use your left hand to press the leg down while simultaneously trying to swing it back to its starting place. “Move in and out of the stretch over that last 20-30 degrees of range so that the lateral hip muscles are activated while the stretch is imposed,” says Blazevich. Do 3-5 reps per side.