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Chris, you are of course right here. I explained the way we do it to these
people already. I just don't have time to included it in every post. The
WKPP methods are, as usual, perfect.
> Breaks have to be at less than 20 minutes, and you do not change the
total time for them. I already explained that.
George,
The 20 minutes on high PO2 and 5 minutes "air" break is old school
still taught by the usual suspects. You, and others in the WKPP, have
realized that shorter on times not only lower the chances of an oxtox but
also prevent the physiological changes that inhibit rapid gas exchange.
There is a study done in Hawaii at the Straub Clinic (Youngblood, Nakano,
et.al.)* that supports this view. When subjects were exposed to a PO2 of
1.5, 84% showed evidence of vasoconstriction. Of those that evidenced
vasoconstriction, the average onset time was 18.6 minutes. There were some
factors (inability to clear ears) that may have increased this time
slightly. The interesting thing is that 43% of those subjects indicated
vasoconstriction within 13 minutes and a third were under 10 minutes. This
shows that the onset of vasoconstriction occurs very rapidly and is probably
even faster when exposed to higher PO2 levels. I believe that you are using
a 12/6 toggle and Landon is using 10/5 which is more in line with what this
study shows than 20/5. Obviously, once the vasoconstriction begins, any time
spent supposedly offgassing is wasted.
Feel free to repost this as you see fit.
C.
Chris Elmore
(803) 748-3055 mobile
* I have a copy of the report but not the journal citation. I'm looking
for where it was published and give you that info when I get it.
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<DIV><FONT face=3DArial><FONT size=3D2><FONT
color=3D#0000ff><SPAN=20
class=3D635193611-24022002>Chris, you are of course right here. I =
explained=20
the way we do it to these people already. I just don't have time to =
included it=20
in every post. The WKPP methods are, as usual, perfect. =
</SPAN><SPAN=20
class=3D635193611-24022002> </SPAN><SPAN=20
class=3D635193611-24022002> </SPAN></FONT><BR></FONT></FONT>
</DIV>
<BLOCKQUOTE dir=3Dltr style=3D"MARGIN-RIGHT: 0px">
<DIV>
<DIV><FONT face=3DArial size=3D2>> Breaks have to be at less than =
20 minutes,=20
and you do not change the total time for them. I already explained=20
that.</FONT></DIV></DIV>
<DIV><FONT face=3DArial size=3D2></FONT> </DIV>
<DIV><FONT face=3DArial size=3D2>George,</FONT></DIV>
<DIV><FONT face=3DArial size=3D2> The 20 minutes on =
high PO2 and=20
5 minutes "air" break is old school still taught by the usual =
suspects. You,=20
and others in the WKPP, have realized that shorter on times not only =
lower the=20
chances of an oxtox but also prevent the physiological changes =
that=20
inhibit rapid gas exchange. There is a study done in Hawaii at the =
Straub=20
Clinic (Youngblood, Nakano, et.al.)* that supports this view. When =
subjects=20
were exposed to a PO2 of 1.5, 84% showed evidence of vasoconstriction. =
Of=20
those that evidenced vasoconstriction, the average onset time was 18.6 =
minutes. There were some factors (inability to clear ears) that may =
have=20
increased this time slightly. The interesting thing is that 43% =
of=20
those subjects indicated vasoconstriction within 13 minutes =
and a=20
third were under 10 minutes. This shows that the onset of =
vasoconstriction=20
occurs very rapidly and is probably even faster when exposed to higher =
PO2=20
levels. I believe that you are using a 12/6 toggle and Landon is using =
10/5=20
which is more in line with what this study shows than 20/5. Obviously, =
once=20
the vasoconstriction begins, any time spent supposedly offgassing is=20
wasted.</FONT></DIV>
<DIV><FONT face=3DArial size=3D2> Feel free to =
repost this=20
as you see fit.</FONT></DIV>
<DIV><FONT face=3DArial size=3D2>C.</FONT></DIV><FONT
face=3DArial =
size=3D2>
<DIV><BR>Chris Elmore<BR>(803) 748-3055 mobile</DIV>
<DIV></FONT><FONT face=3DArial size=3D2></FONT> </DIV>
<DIV><FONT face=3DArial size=3D2></FONT> </DIV>
<DIV><FONT face=3DArial size=3D2>* I have a copy of the report but not =
the journal=20
citation. I'm looking for where it was published and give you that =
info when I=20
get it.</FONT></DIV></BLOCKQUOTE></BODY></HTML>
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