dumpsterDiver
Banned
- Messages
- 9,003
- Reaction score
- 4,652
- # of dives
- 2500 - 4999
How does one inhale? What makes it happen? Never having been presented with this problem before, I think that mechanism is an issue here.
You can lower the diaphragm, expand the chest, and raise the collarbone. These actions increase the size of the chest cavity, which causes air to come in through the mouth and nose. A free diver frequently does all three, at which point no more air can be inhaled because the chest cavity is already at maximum size.
When the diver descends, the gas within the lungs becomes more dense, causing the lungs to shrink. Does this cause the chest cavity to shrink as well? Descending also cases the air in the sinuses and middle ears to become more dense as well, but does that cause the skull to shrink?
I certainly have not tried it, but I would guess that a free diver who has descended with full lungs would be unable to inhale without first exhaling at least some of the air inhaled at the surface.
Wow,,, the chest of a freediver compresses a lot. You get very heavy when freediving. As an instructor you should know that the sinuses in the head are a rigid air space and a diver (freediver or scuba) will experience barotrauma if the internal and external pressure is not equalized.
Does the skull shrink? I will leave that one unanswered. Maybe it is a Halloween question?
An no a freediver does not have to exhale air from the surface in order to inhale at depth??? I don't even have a clue how you would come to that "guess"?
As I already described, take a deeeep breath from a scuba tank and start swimming down hard. After 20 or 30 feet, you will be able to inhale and inhale and inhale as you descend- completely analogous to being able to exhale and exhale and exhale when a scuba diver does a free ascent.