1. Lay on your back on a soft workout surface with your arms laid out by your sides, and your legs elevated in the air with your knees bent at a 90-degree angle. Your shins should run parallel to the floor. This is the starting position
2. While grounding your arms, contract your abdominal muscles to pull your legs towards your chest while simultaneously elevating your glutes off the floor 3. Briefly hold the contraction before slowly relaxing your abdominal muscles to lower your lower body back down to the starting position
The primary muscles used in Reverse Crunches are the Abs.