Crunch - Hands Overhead
This variation makes it tougher than regular crunches. Lie on the floor with your knees bent. Keep your feet flat on the floor. Stretch your arms overhead and cross your palms. Curl your upper body forward and bring your shoulder blades just off the floor. Keep your arms aligned with your head,neck and shoulder. Don't move them forward from that position! Slowly lower down after squeezing your abs tight.