Personal Trainer Cassandra German recommends a reverse crunch for your lower abs and lower back. To perform this exercise, follow these steps:
Step 1: Lay on your back making sure to keep the lower back flat (your hand should not be able to slip underneath your back ). Toes are up with your heels to the ground, knees bent. Arms rested to your sides.
Step 2: Keeping the legs in the same position pull your knees up to your chest .
Step 3: Come back to initial starting position. Remember to keep your back flat against the floor at all times.
Repeat steps 1- 3. Try 3 sets of 10 to 15 reps!