1. Start position. Lie prone, resting on the forearms with the upper trunk lifted off the mat. Position the forearms so the upper arms form an approximately 90-degree angle with the trunk. Hands are on the mat next to each other, fists clenched. Legs rest on the mat straight to the back and together, feet gently pointed.
2. Inhale. Lift both legs about 2 inches (5cm) off the mat. Bend one knee so that the heel comes toward the buttocks with brisk dynamic. See the main muscle illustration.
3. Exhale. With the same brisk dynamic, straighten the bent knee as you bend the opposite knee so that the opposite heel comes toward the buttocks as shown. Repeat the sequence 10 times on each leg, 20 times in total.