Obnoxious breathing

I can recall a few years ago reading a story in Navy Times or a Navy Safetygram about a Dive School student who killed himself "practising" his breath holding. (Perhaps those of you who live in Coronado can back me up on this one?) Apperantly, this young lad decided he needed to be able to stay underwater longer without the aid of oxygen, and being a highly motived sailor, he thought he would work on it extra. Went to the training tank at the Naval Amphibious Base, and "worked" on his breath holding by hyperventilating just before going underwater. As several participants have pointed out, the urge to breath is not caused by lack of oxygen in the blood stream, but an excess of carbon dioxide. By hyperventilating, he drove the CO2 level down artificially, and set up conditions where he could pass out from lack of oxygen before his CO2 urge to breath would motivate him to surface. The final factor in the equation was that he appeared to have some trouble staying submerged with his lungs chock full of air. So, when he went under, he hooked his fingers around a water intake plate at the bottom of the pool. Probably some of you can fill in the rest of the story. He passed out before he felt the need to breath, and his fingers locked on the grate. By the time the lifeguards noticed that, gee, he's been under a long time even for a SEAL wannabe, discovered him unconscious, managed to get his fingers off the grate, and started CPR, he was already gone. Do I think you will kill yourself, even with HIGHpoxic sets? Clearly not! But, as Emmett and others so sagely pointed out, doing low breath sets for the wrong reasons or using the wrong technique is at best useless, and at worst counterproductive. And, most important, do NOT hyperventilate before doing these sets! Matt

I can recall a few years ago reading a story in Navy Times or a Navy Safetygram about a Dive School student who killed himself "practising" his breath holding. (Perhaps those of you who live in Coronado can back me up on this one?) Apperantly, this young lad decided he needed to be able to stay underwater longer without the aid of oxygen, and being a highly motived sailor, he thought he would work on it extra. Went to the training tank at the Naval Amphibious Base, and "worked" on his breath holding by hyperventilating just before going underwater. As several participants have pointed out, the urge to breath is not caused by lack of oxygen in the blood stream, but an excess of carbon dioxide. By hyperventilating, he drove the CO2 level down artificially, and set up conditions where he could pass out from lack of oxygen before his CO2 urge to breath would motivate him to surface. The final factor in the equation was that he appeared to have some trouble staying submerged with his lungs chock full of air. So, when he went under, he hooked his fingers around a water intake plate at the bottom of the pool. Probably some of you can fill in the rest of the story. He passed out before he felt the need to breath, and his fingers locked on the grate. By the time the lifeguards noticed that, gee, he's been under a long time even for a SEAL wannabe, discovered him unconscious, managed to get his fingers off the grate, and started CPR, he was already gone. Do I think you will kill yourself, even with HIGHpoxic sets? Clearly not! But, as Emmett and others so sagely pointed out, doing low breath sets for the wrong reasons or using the wrong technique is at best useless, and at worst counterproductive. And, most important, do NOT hyperventilate before doing these sets! Matt