This exercise is used to strengthen the abdominal muscles, while also stretching your back and hamstrings.
Lie down flat on your back with your lower back pressed into the floor. Next, slowly elevate your legs up until they are perpendicular to the floor or they form a 90 degree angle with your torso. Keep your feet together while doing this. Now, raise your arms so that they make a 45 degree angle with the floor. Now, while keeping your lower back on the floor begin to raise your torso up off the floor. As you do this, try to touch your toes with your finger tips. Then, slowly return your torso to the floor and repeat until you have completed your set.
Keep your arms straight throughout this movement and also your feet should be parallel with the floor. Keep a slight bend in your knees while you perform this exercise.