Materials needed:
1. Blackboard and chalk, or flannelboard with large lung diagram prepared.
2. Balloons, which have been prestretched to make them easier to blow up. (People should be cautioned not to overblow the balloon.)
IF ALL the little air sacs in the lungs were flattened out the surface area would be about the size of seven large bed sheets or the size of a 15' x 30' room. Every hour, at rest, the lungs carry in and out about 1,500 gallons of air.
We will draw a diagram of the lung on the board, and show you the different volumes of air involved in your breathing.
(If you have a hook-and-loop board or flannelboard and you care to prepare the lung in sections, with the labels, it will probably show up better than a line drawing on the blackboard.)
Tidal Air
At each quiet breath about 5OOcc or one pint of air is taken in. This is called tidal air because it ebbs and flows like the tide. It is only one sixth of the amount of air already in the lungs, yet it suffices to supply the body with oxygen while at rest.
Complemental Air
When you take your deepest breath you take in about three additional pints of fresh air. This is called complemental air, because it complements or adds to the tidal air as a source of oxygen. When breathing quietly, only the tidal air, or one pint, goes in and out of your lungs.
Supplemental Air
Air breathed out by force is called supplemental air, for obvious reasons.
Residual Air
The amount of air that always remains in the air sacs is about two pints, and is called residual air or reserve volume.
Vital Capacity
Vital capacity is the greatest amount of air that you can breathe out after you have taken your deepest breath. Physical exercise increases vital capacity. Posture may alter it. It is greater while standing than when lying down.
The reason for deep breathing is to bring more oxygen to the blood and to increase the exchange of carbon dioxide. Our goal is to develop the greatest possible vital capacity, or room in the lungs, so that we can use more oxygen. We can accomplish this if we breathe deeply, sit and stand straight, and exercise hard enough to require deep breathing. With each breath you:
1. help lift the blood from the lower body to the heart
2. massage the liver and the stomach
3. draw in a large amount of oxygen to vitalize your tissues
4. get oxygen to change your food into energy.
No wonder Ellen White says, "In order to have good blood, we must breathe well." --Counsels on Health, p. 59.
So your goal is always to get more oxygen. [Review the four volumes and get the audience to answer. Example: Tidal Air? Answer: one pint.] Try deep breathing when you are tired and see how it rests you. Now let's experiment. Let's breathe together. Stand, please, and place your hands on your chest and feel your rib cage. Breathe deeply. Now, all the way out. Did you feel your rib cage expand? Now do it again.
The muscles that control the ribs, backbone, and breastbone act to make the rib cage expand; the diaphragm muscle goes down to make more room. Air rushes into the lungs, and the elastic lungs balloon out they expand to let the air in. Let's try to count as we exhale and see how far you can count on that one breath. When you have to take another breath please quit counting. Ready, all together, breathe in now out 1, 2, 3, 4, et cetera as long as you can. [Do this twice.]
Now we will use the balloons that have been given to you so you can see the relationship of the volume in the lungs. The adult lung varies with the size of the person, but is often about ten inches long, although it is wider than this balloon. If your balloon is hard to blow, stretch it some more.
First, take a normal breath. Be careful. You're so used to inhaling deeply before blowing up a balloon that it's likely to be automatic. Just take an ordinary breath and blow it into the balloon. [Have those present hold these up for everyone to see.] Now take a real deep breath and blow that into the balloon. Be careful not to pop it. See the difference? That demonstrates why it's so essential to make an effort to get at least ten deep breaths every day.
