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Ruud_G

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 #16 
Now I have 4. With the last two being able to go deeper in terms of wattage [wink]

End heart rates in all 3 are almost the same. In the workout 1 which was depicted as one of the 2 lines Juerg had already posted my HR was overall highest. With these last two workouts from yesterday and today actually both had lower HR overall but as said ended up at the same level as the first two.

O2Hb trend from my worst performance shows lowest absolute value. O2Hb trend from best performance shows highest O2Hb trend. My second best performance (from yesterday) has an O2Hb trend which actually is just a bit above the worst performance but flattens out in the last full step towards the end which actually then comes very close to my best performance of today (1 min more in 390 watt than yesterday [wink] as said both these best performances had a lower HR trend especially from the last 3 steps onwards. This really points me towards CO since (apart from my worst performance) TV/RF really differed that much.

Nice rainbows hey?

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juergfeldmann

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 #17 
Nice  feedback. 

Short  general  thought of question.
 " If we see a  " flat SmO2  towards the end or  at the last  step.
 What does  that mean ?
 Trick  question.
 Better is to ask   or  hint. Look at tHb  reaction  as a flat  SmO2  not   always means  what the cookbook suggest.
A  flat SmO2  could indicate  in connection with tHb  still  that you use more O2  than you deliver or  it  can mean that you actually  deliver more than  you  see.
 How  do  you  see that on tHb ?
Ruud_G

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 #18 
An increase in tHb I think Juerg
Andrew

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 #19 
I have not seen the slide from Jiri regarding the U-shaped tHb curve in a standardized step test...but I would like to take a stab at why this might occur. I presume to reasons could be multi-factorial, and I am sure to oversimplify possible causes for increasing tHb at increasing intensities.

1) starting at baseline there is x amount of blood circulating in resting muscle
2) initial drop due to compression
3) return to baseline (or higher) depending on how easy initial intensity is. this is in response to increasing cardiac output (usually due to HR increase) balanced against relatively gentle compression forces
4) as intensity increases with each subsequent step, compression forces overcome delivery (despite increasing cardiac output), and cause a subsequent drop in tHb
5) balance is achieved at the bottom of the U in this particular assessment (compression forces balanced against cardiac output and local vasodilation).
6) Now the interesting rise in tHb with subsequent steps, despite continued increase in compression forces. I think a number of factors could contribute...
    a) vasodilation due to relative hypercapnia
    b) relative increasing cardiac output (compared to compression), now as a result of increasing stroke volume in addition to increasing HR...resulting from increasing venous return (more compression on venous system) AND increasing hypercapnia

I hope I have not confused the issue with my guesses, but that is how I have been interpreting this trend. I hope that I am still on the right track.


DanieleM

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 #20 
@Andrew, just a couple of points:
4) as intensity increases with each subsequent step, compression forces overcome delivery (despite increasing cardiac output), and cause a subsequent drop in tHb
We need to consider two things:
1. Cardiac Output and Leg Blood Flow increases linearly during the first steps and usually level off later (HR not big rise, SV could be stable or even lower).
2. If your theory is true I should see a big overshoot if I suddently stop (definetely at higher level than start), which at least in my case is not present.

6) Now the interesting rise in tHb with subsequent steps, despite continued increase in compression forces. I think a number of factors could contribute...
    a) vasodilation due to relative hypercapnia
    b) relative increasing cardiac output (compared to compression), now as a result of increasing stroke volume in addition to increasing HR...resulting from increasing venous return (more compression on venous system) AND increasing hypercapnia

For the reasons I mentioned above I don't think option b is valid.
I would say vasodilation due to hypercapnia + other factors (metabolites and deoxygenation sensors) 
Andrew

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 #21 
Daniel, thanks for the insight into my ideas, and I think I understand your critique of my theory. However, if the SV was increasing due to increased genius return, resulting from increased compression forces, and the forces were suddenly removed...then the SV would drop, and cardiac output would drop, which would partially negate the expected spike in tHb.

To respond to your points...
"1. Cardiac Output and Leg Blood Flow increases linearly during the first steps and usually level off later (HR not big rise, SV could be stable or even lower)."
In the step test I was referring to with the "U-shaped" tHb curve, leg blood flow was seen to Decrease in the initial steps.

"2. If your theory is true I should see a big overshoot if I suddently stop (definetely at higher level than start), which at least in my case is not present."
Again, I was discussing the specific U-shaped curve of the original past which was done as a simple step test, and not as a 5-1-5 with the inherent sudden stops, so we have no indication of whether an overshoot would occur in this individual or not.
DanieleM

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 #22 
I think we are jeopardizing  Ruud assessment here (sorry about that), so I will open a new topic about the U-shape tHB.

Ruud, great work!
One thing I can you see from your best performance was the SmO2 still at balance for a while.
Probably delivery) is working well.
Perhpas on the "worst" performance, delivery was not enough (an in fact you reached your highest HR) to keep it at balance and SmO2 started to drop earlier.
Ruud_G

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 #23 
Ho Daniele. No problem. To see discussions is always nice!! I think if Juerg adds the two graphs of my two TIPs which basically give very very similar results more light might be shed on the "assessments"

The U shaped form is still intruiging though
juergfeldmann

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 #24 
All you guys  are great.
All other regular readers  short  question:
 Where do you find as  general  practical forum, where we have the fun  to discuss great open questions   like this.
??
 As  all can see we drifted  far of  an easy idea  of NIRS into a  real  practical  discussion on how we  apply  and sue  NIRS  as coaches and close the   bigger and bigger gap  between   since  and  coaching. That is the whole purpose of this    nice discussion.
 I will   follow Ruud's advice  and will  take a lot of time over the weekend  to   give some additional thoughts . No  solutions  and no  real    clear answer  as  there is much more behind this great  U  shape    situation.
  Just very short before  work.
 Every single  idea  and answer  is  true  and  has  to be combined. I will show  real   case studies  to support  Daniele's  point  but as well to support  Andrews  point    as this  questions  started out  for us  many years back   when we   had   to do the big step    form  using a  LT  or  any  great 100 %   idea  to a  disappointing   finding, that  it is  not that easy but  if we have live  feedback it will  be sure  easy as we can see what happens.
 In this  search we  completely   moved  out of practical options  and   connected  tools  for a close to 100'000 $  system. Very unrealistic  and very stupid  to think it  will ever  be used. Now  after all this years  we are down to a  super  cheap  solution  with MOXY  and all comes together  with  some  small  disadvantages  . We have  to think through different options  and this  what happens here.
 Now  suddenly we    do  what we should do  , using our  physiological ideas  and brains   to  avoid  calculations. So  super fun   and will be back  with lot's of back ground  information  to show  how this  may fit together  with a simple tool.
juergfeldmann

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 #25 
Short  add on  to Ruud's  point
 The U shaped form is still intriguing though

 Hint  remember the  "cook book"   if you like to  stimulate  utilization  than  reduce  delivery ?

  If  we go all out intensities we  create a delivery problem  so  we will stimulate utilization but overload  all systems   relative uncontrolled.

So  really this is  NOT a  reduction in delivery  but simply a all out overload.  So that brings  us  back  to Hans  Selye  and stress.
  Stress is not   fixed on all out   overload but rather on different  unusual loads.
 So  what does  an U  shape tHb  curve  would  be suggesting  for us ?
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