Lie on your back on the floor with your knees bent. Flatten your back against the floor by tightening your abdominal muscles and bending your pelvis up slightly. Hold for a few seconds. Repeat.
Roll your foot around with the heel up to move the ankle joint; switching the direction that you roll periodically.
Sit on the floor with your legs stretched out in front of you with knees straight and feet upright. In a slow, steady movement, lean forward at the hips, keep your knees straight, and slide your hands forward. Extend as far as you can.