Dive4air
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Tanya Streeter, is on Discovery Channel tonight, in the US broadcast, on a Free Diving show. I am a scuba guy myself, but i think this is still interesting.
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Thanks for the info. I did a freediving clinic with Tanya, she is very talented.Dive4air:Tanya Streeter, is on Discovery Channel tonight, in the US broadcast, on a Free Diving show. I am a scuba guy myself, but i think this is still interesting.
I watched this last night, it was pretty cool stuff. I was curious, if you can clear your ears OK, does it otherwise hurt free diving down to 200 ft? Does it hurt having your lungs squished down so much? Also, I assume he's blowing air through his nose to prevent mask squeeze, when at 200 feet doesn't that use up a chunck of what little air volume your lungs have left?Dive4air:Tanya Streeter, is on Discovery Channel tonight, in the US broadcast, on a Free Diving show. I am a scuba guy myself, but i think this is still interesting.
Dive4air:I thought it was fascinating that you can consciously control your heart rythm to the point of overcoming the natural instinct to breathe. It's like these guys go into the pre-death tunnel vision, but they are able to bring themselves back out of it. Ever see the movie flatliners? This gets close. So much for people who see the bright lights in near death experience...
hey BobbyF, great response. There are actually three different types of blackout in the sport of freediving, they are as follows:Bobby F:Shallow water black out is from the affect of preassure at depth which effectively ads an atmosphere to the affects of gases for each 33 ft. In simple terms your body needs about 15% 02 to keep you from blacking out. At 200' that is seven ATM's compared to one at the surface. Since you are breath holding you are using up 02 during the dive. At 200' you could be down to 10% 02 in your body but the affects at a depth of 200' is like having 70% 02. When you come back up, at around 15' this low 02 will now cause you to black out since this is where you drop below the 15% threshold. Hence it is called shallow water black out.
Free divers tend not to equalize the ears by way of pinching the nose and blowing since this wastes energy, we usually roll our jaw which with practice works just as well.