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ryinc

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 #1 
Here was a post from a popular cycling forum in South Africa that i thought the moxy forum might be interested in. 

I imagine that NIRS/Moxy would be quite a useful tool in this situation (even though tHB absolute values need to be treated with care).

"I donated blood yesterday morning at about 09h00. At properly before hand and definitely afterwards. :D 

Went out for a ride this morning and it felt as if I have lost all my strength. Even the flats were a big ask at my normal pace at which I ride. I am not even talking about the hills.

I was really flat and my heart rate went through the roof!


I would like to know if the blood donation had anything to do with my state or is it just a general flatness.

Before today's ride I took two days off the bike after a tough week-end. 75km on Sat and 105km on Sun, both at an ave speed of 32 km/h including some proper hills.

Could it be that dreaded bonk after a rest day?

What are some of the experiences of blood donors on the Hub? 

And, how long will it take before I am right as rain again. Racing 100km on Sunday!!!! "


From all the discussion on the forum, we know that the on the day this athlete probably had reduced tHb (due to the blood donation), resulting in reduced SV, meaning HR had to compensate ("my heart rate went through the roof") at "easy" loads making the athlete feel flat.

Cheers
Ryan
juergfeldmann

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 #2 
Ryan , great  example  and  that is  what surprised  me all over , when I look at many forums,  the  questions are great  the answers  often as well. So your  answer is  given   and I hope all regular readers   may  feel the  same. Pre load is one  and  delivery ability  is the other. The preload can be  relative fast  solved  the delivery less fast.
 When  we used   Portamon  that's  what where we looked  at  very early on  what happens  after  blood  donation and  after  blood infusion. A   pretty basic  question  for all looking to test some  feeling  for NIRS  ability. Including the inversion table as a base   assessment  for  orthostatic  reactions.
 That's what surpises  me  , when I look at many great nirs  studies, the lack  of combination with  cardiac  and  respiratroy tools  as well as SEMG, so that many studies   stop   short before possible answers  and end  with conclusions which may lead  into the wrong direction.
  One of them is  the  webinar where  we  tried  to discuss on Nadir  of VO2  max,  lactate  top level and SmO2 . If  you go back   and take the graph, blow  their graph  up you can see  that  there is  no common Nadir. I was hoping to have the raw datas  sent so  we can move it in a bigger zoom in to show  that . 

Summary : Blood donation takes  O2  carrier  and   volume  away  from the current systems  and   in the short term you have to try  to compensate  and not many options  immediately some better one  after  1  - 2  days   and than we have to be patient.

Below a graph  I showed  many times  but now  with  some nice   steps  forward  they make  more sense for many. Including the above great  section  from Ryan's post.

vo2  over all.jpg 


Than  you try to reduce  the needed  tools  to  NIRS/ MOXY  and it  could look like the  below    picture.

moxy vo2 2.jpg 


Now in the first picture  you can see the  physiological training plan  and what you like to  try to target and improve  and how  a successful  plan will show up  with a  specific  improvement.


An assessment is  what  you do  to find  out . A  test misses the points,  as it is based on a   maximal   result  where  all the systems  are involved  but we do not know which one   was  the  weakest link.

juergfeldmann

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 #3 
I had  an interesting  talk on a phone  with a coach last night on this  subject  just in the opposite  direction. But  blood donation will in fact have  some similar reactions  as a short  term  lactation survival ( plasma increase  and a   middle  term   structural adaptation blood cell  production.

Here  om far back some  ideas
 
Sports Med. 1992 Jan;13(1):37-49.

Hormonal and plasma volume alterations following endurance exercise. A brief review.

Abstract

Plasma volume expansion usually occurs with acute endurance exercise and endurance training both in humans and in animals. In most cases, the increase in plasma volume is associated with lower haematocrit without red cell mass change or an actual reduction in red cell mass, causing relative or true anaemia, respectively. The combination of exercise and heat acclimation (which produces also hypervolaemia, but at a lesser degree than exercise) enhances hypervolaemia induced by exercise training alone. The onset of the phenomenon is extremely rapid: hypervolaemia is observed within minutes or hours of the cessation of exercise. However, 2 days are necessary to reach peak plasma volume expansion after a marathon run or longer race. The magnitude of this natural expansion ranges from 9 to 25%, corresponding to an additional 300 to 700 ml of plasma. The magnitude of this alteration depends on preceding exercise: ambient conditions, intensity and duration of exercise, body posture and frequency of the exercise bouts. The larger the reduction in plasma volume during exercise, the greater the subsequent hypervolaemia. The hydration status of the subjects before and during exercise might modify also plasma volume changes: sufficient fluid ingestion can lead to plasma volume expansion even during prolonged exercise. Fluid-regulating hormones (aldosterone, arginine vasopressin and atrial natriuretic factor) in conjunction with an elevation in plasma protein content promote hypervolaemia. However, the role and the mechanism of the increase in protein mass remain unclear and the hormonal role in the induction of chronic hypervolaemia is still an open question. Hypervolaemia can improve performance by inducing better muscle perfusion, and by increasing stroke volume and maximal cardiac output. By increasing skin blood flow, plasma volume expansion also enhances thermoregulatory responses to exercise. This leads to the important concept of optimal plasma volume and haematocrit, and performance.



PMID:
 
1553454
[PubMed - indexed for MEDLINE]

We did in the late  1980    some stdueis where we  actually had athletes  donating blood  and than  moved  for 3  weeks in  altitude  to see the  reaction   in this cases.

  Now   the discussion I had last night was  with a very different " coach  a  horse  coach or trainer and we had  the discussion we started   in here but much earlier on the Fact   forum  where we had a  designated  horse  section. The discussion is  about spleen dumping  and  possible options  to pick the optimal time  with NIRS .
  Now  this spleen dumping  idea  is not very nicely   studied  in humans but it exists  as well and Jiri  Dostal  from Prag , the leading NIRS  persons  out  there  sent me as well back some  interesting studies  on this. Have to  see, whether i  can find them in my  regular mess.
juergfeldmann

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Posts: 1,501
 #4 
I just got  one interesting email. Summary  Question  how muhc plasma  volume  is  needed  to get  an advantage.
 First   plasma volume  increase has as  so  often a positive and negative effect. 
 Positive  preload  so increase in SV.
 negative  dilution of  Hct  so negative in O2  delivvery.
  There are some  again old studies on this  from the early  1990  and here  one nice one   who gives some nice feedback on the volume and why natural plasma expansion  workouts actually can work .
 
nt J Sports Med. 1990 Apr;11(2):116-9.

Maximal oxygen uptake relative to plasma volume expansion.

Abstract

Controversy exists as to whether plasma volume (PV) expansion has the potential to increase maximal oxygen uptake (VO2max). In the present study, VO2max and exercise time to fatigue were measured in nine untrained men when plasma volume (PV) was normal and then again on the next day following two levels of PV expansion. Resting PV was expanded (via intravenous infusion of a 6% dextran solution) by 282 +/- 16 ml (i.e., PVX-1) and then by 624 +/- 26 ml (i.e., PVX-2). PVX-1 increased stroke volume (CO2 rebreathing) during submaximal exercise by 15% (P less than 0.05) above normal levels. VO2max following PVX-1 was increased 4% (P less than 0.05; 3.78 to 3.92 l/min) despite a 4% reduction in hemoglobin concentration. Exercise time to fatigue was also increased (P less than 0.05). PVX-2 resulted in an 11% (P less than 0.05) reduction in hemoglobin concentration during maximal exercise and a return of VO2max and exercise time to normal levels. In summary, we have observed in untrained men that 200-300 ml of PV expansion increases SV, measured during submaximal exercise, yet causes only a small amount of hemodilution. As a result, VO2max is increased slightly and performance is improved. Further PV expansion to levels 500-600 ml above normal results in an excessive hemodilution and a subsequent decline in VO2max and performance to normal levels. There is an optimal PV for eliciting VO2max in untrained men which appears to be approximately 200-300 ml above their normal levels.

bobbyjobling

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 #5 
Juerg, referring to your last post. My thoughts: although a greater plasma volume is not ideal to improve vo2peak compered to a more "ideal" mix. In an endurace sport lasting 3 to 4 hours would it still be advantageous to have a greater plasma volume to balance body heat / fluid loss in the race event?
Jiri Dostal

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 #6 
Juerg, thanks a lot, I am not an expert :-) I just try to understand the great NIRS world. Anyhow... Yes, I have sent you some spleen dumping files, but unfortunately I lost them. 

I talked about the whole blood manipulation story ( blood donation is in fact blood manipulation) with prof. Schmidt few months ago. Here is a picture from his publication explaining what happens with the Hb, blood volume and thbmass after different scenarios.

Blood donation is under B and C, spleen dumping under D.

  VýstÃ…â„¢ižek.JPG

Jiri Dostal

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 #7 
Just to add one more thing. Yes, CO is very important. However in order to have the whole picture of blood carrying capacity we should also consider hematocrite ( this changes during the exercise due to physiological volume expansion or reduction)  and thbmass ( this is very stable value). All three components plays significant role with O2 delivery. And here is the answer to the acute and chronic reaction to the blood donation.
bobbyjobling

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Posts: 219
 #8 
Thanks Jiri, the chart is very interesting.
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