Instructions:

1. Sit on the floor with your back against a wall and your legs extended in front of you.
2. Bend your knees and place your feet flat on the floor, hip-width apart.
3. Place your hands behind your head with your elbows pointing outwards.
4. Engage your abs and lean to one side, bringing your elbow towards your hip.
5. Pause for a moment, then return to the starting position.
6. Repeat on the other side.
7. Continue alternating sides for the desired number of repetitions.