This exercise uses the same initiation as The Hundred Prep, and it uses the sniffing breath to build endurance in the abdominals and diaphragm
To do this exercise you will need a mat.  Start by lying on your back with your knees bent and your feet planted into the ground.  Inhale as you float your arms into the air above your shoulders, and then exhale as you press your hands towards the ground and lift your head, neck, and shoulders.  Next, start making small pumps with your arms as you start the sniffing inhales.  Take five sniffs of air in, and then blow five sniffs of air out.  Repeat for then cycles and then lower the head neck and shoulders to the ground.
Things to think about.
If you have osteoporosis you should do this exercise with your head down.
The Hundred is often thought of as a great abdominal exercise.  When in actuality it is an exercise designed to strengthen and tone the diaphragm.  As you are doing this be sure that your is clear and that each sniff and each blow creates movement in the ribcage and soft tissue.
Take care of your neck.  If you feel tension in the back of your neck, be sure to check your breath and see that your breastbone is releasing towards the ground.