I was reading a post Wal made on an Aussie site the other day (http://www.spearfishing.com.au/cgi/...oard=freecorner;action=display;num=1090937078), which basically has two graphs from him - one of a 7 minute static, and another a 2:30 exhale (on a pulse-oximeter). It got me thinking of a course I did a couple of months ago, and a few things I learnt.
The course was an aviation one, and related primarly to the effect of high performance aircraft on the body. There were four main points I got from it with relation to freediving (passed the test so dumped the rest
The first is to do with hypoxic training - there's always a big emphasis on how climbing to a higher altitude means less dense air, hence less O2, hence increased production of Hb, etc. One of the primary factors affecting air density though is temperature - basically, for each degree (celcius) increase in temperature, its equivalent to climbing an additional 120'.
An example - take the difference between Canberra and Cairns. Canberra has an average temperature of about 15 degrees, whereas Cairns is about 30 degrees. Canberra has an elevation of about 1800'; Cairns is pretty much sea level. I was always of the impression that when I went home from Canberra to Cairns, I was moving into more dense air, but if you crunch the numbers, it works out the same: Cairns is an extra 15 degrees (ie 30 - 15), multiply by 120' = 1800'. Using this logic, maybe it would be more beneficial to not necessarily train higher (though that definitely helps) but also hotter, then when its time to set a record, head for colder water?
The second point is to do with hypoxic symptoms. Basically, each individual will react to hypoxia differently, however the individual symptoms will not change over time. The air force here pushes this point by exposing all pilots (in a controlled environment of course) to low blood oxygen saturations, on a regular basis. Every three years we're all required to jump into a barometric chamber to "remember" what it feels like to be hypoxic. I'm not advocationg that everyone goes out and blacks out just to see what its like, but I've seen many arguements that each time is different - that's not what we've been shown.
The third point is probably the least practical of all of them, but I thought I'd throw it in for good measure
Finally, one that *may* be a little more practical (not sure, haven't tested it) - under negative G (ie standing on your head), heart rate decreases dramatically. On our course of 20 studs, the smallest drop I saw was 15bpm after 15s inverted, and the largest was 30bpm after 15s. Additionally, all the blood drains out of the extremeties (ie arms and legs) - maybe doing a hand stand is the way to go with static? I'm not sure how well the heart would cope with pumping the blood from the head back up, but it would seem to keep the constant supply going from the heart to the brain?
I'm not sure if any of that's any use to anyone, I've been meaning to write it up for a while. If anyones keen on anything there and wants more info, throw me a message and I'll see if I can help you out
Safe diving,
Brad
The course was an aviation one, and related primarly to the effect of high performance aircraft on the body. There were four main points I got from it with relation to freediving (passed the test so dumped the rest
The first is to do with hypoxic training - there's always a big emphasis on how climbing to a higher altitude means less dense air, hence less O2, hence increased production of Hb, etc. One of the primary factors affecting air density though is temperature - basically, for each degree (celcius) increase in temperature, its equivalent to climbing an additional 120'.
An example - take the difference between Canberra and Cairns. Canberra has an average temperature of about 15 degrees, whereas Cairns is about 30 degrees. Canberra has an elevation of about 1800'; Cairns is pretty much sea level. I was always of the impression that when I went home from Canberra to Cairns, I was moving into more dense air, but if you crunch the numbers, it works out the same: Cairns is an extra 15 degrees (ie 30 - 15), multiply by 120' = 1800'. Using this logic, maybe it would be more beneficial to not necessarily train higher (though that definitely helps) but also hotter, then when its time to set a record, head for colder water?
The second point is to do with hypoxic symptoms. Basically, each individual will react to hypoxia differently, however the individual symptoms will not change over time. The air force here pushes this point by exposing all pilots (in a controlled environment of course) to low blood oxygen saturations, on a regular basis. Every three years we're all required to jump into a barometric chamber to "remember" what it feels like to be hypoxic. I'm not advocationg that everyone goes out and blacks out just to see what its like, but I've seen many arguements that each time is different - that's not what we've been shown.
The third point is probably the least practical of all of them, but I thought I'd throw it in for good measure
Finally, one that *may* be a little more practical (not sure, haven't tested it) - under negative G (ie standing on your head), heart rate decreases dramatically. On our course of 20 studs, the smallest drop I saw was 15bpm after 15s inverted, and the largest was 30bpm after 15s. Additionally, all the blood drains out of the extremeties (ie arms and legs) - maybe doing a hand stand is the way to go with static? I'm not sure how well the heart would cope with pumping the blood from the head back up, but it would seem to keep the constant supply going from the heart to the brain?
I'm not sure if any of that's any use to anyone, I've been meaning to write it up for a while. If anyones keen on anything there and wants more info, throw me a message and I'll see if I can help you out
Safe diving,
Brad