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Juerg Feldmann

Fortiori Design LLC
Registered:
Posts: 1,530
 #1 
I got a  great email today  from a very regular reader of  our forum. Great  challenge:
 What is the basic concept  why I would workout  or train  with MOXY  in a few short words.

Here a gentle  shy try  to stay  short.

-Moving  and moving  towards a hard intensity is  not  or nothing about sport  but  ultimately  it is all about   finding the needed  energy to  survive.
- the initial drive is  flight  and fight  followed by ultimate survival of the vital systems.
- as long the  vital systems  , which are mainly delivery system  can afford  to deliver  we will have  every body happy. Once we reach a limitation in the delivery    and  production of  energy  the first place  we will see it because we  can " afford "  for survival reason  to  reduce O2  supply  of this areas are non involved muscles followed by involved muscles.
- Therefor the place where we have the fastest   immediate  feedback  where and when this  takes place is  in the non-involved  and involved muscles.
The only  affordable  and  easy to use live feedback we have  for the moment  is MOXY


Any change in metabolic  milieu in loco motors  muscle  will  sent feedback to the  central governor  system  and than it will be regulated  according.
Stop  or reduce  utilization , regulate  delivery  and so on. All what we  can see    with SmO2  and tHb.

 Is this  a nice  dream  or theory  or  are there  at least some   serious  studies  done  showing this   optional  may in fact  be possible. ?
  Here a  very short  back up  for  what we do. I hope  this hits  a little bit the point , why I like to have  live immediate feedback  during my  activities.

Central and peripheral fatigue: interaction during cycling exercise in humans.

 

Markus Amann

·        

Department of Medicine, University of Utah, Salt Lake City, UT, USA.

Medicine and science in sports and exercise (Impact Factor: 4.48). 04/2011; 43(11):2039-45. DOI: 10.1249/MSS.0b013e31821f59ab

Source: PubMed

ABSTRACTExisting evidence suggests that exercise-induced alterations of the metabolic milieu of locomotor muscle and associated peripheral muscle fatigue affect the central projection of thin-fiber muscle afferents. These neurons provide inhibitory feedback to the CNS and thereby influence the magnitude of central motor drive during high-intensity whole-body endurance exercise. The purpose of this proposed feedback loop would be to regulate and restrict the development of exercise-induced peripheral muscle fatigue and/or associated sensory feedback to an "individual critical threshold." This centrally mediated restriction in the development of peripheral locomotor muscle fatigue might thereby help to prevent excessive disturbance of muscle homeostasis and potential harm to the organism. It seems that the regulatory mechanism is dominant during exercise under "normal" conditions but might become secondary in the face of extreme environmental influences such as severe hypoxia or heat. Most recent data are used to emphasize how the proposed feedback loop might be a key factor limiting performance during high-intensity whole-body endurance exercise.

 



Juerg Feldmann

Fortiori Design LLC
Registered:
Posts: 1,530
 #2 
I got  a nice follow  up question  and as it is  most likely a very common  question I like to answer on here  with permission of the  e mail .

Q:  The concepts sounds  great, but far to  complex  to be used  anywhere. ( Time  , cost  and more )

A:  May be and as I am biased and work since years in this  thought process , I may often forget, that we  talk a different language , when we  explain basic ideas. This is the case in many other areas we  start to look into  and I think it is more a question of giving it at least a try to see, whether we can understand it. I see often, that the main hindrance  is the fact, that some classical  ideas  are getting somewhat under  scrutiny and instead of  asking the same  questions we  get  for MOXY's limitation  and use , we  should apply the same question on what we do  for the moment with VO2, lactate FTP  and more.
 Often  we  have a  kind of a hesitation there to ask critically whether,  what we  do, may need once in a while some reviews  to see, whether it  still applies to what we  learn  new.

 I like to show   2  critical  questions: My point for FTP.

FTP is a perfect system to give  you a very objective feedback on the  average wattage  and  perhaps average  HR  you where able to sustain over a  60 min  cycling load on a relative  accepted  circuit under this  days  conditions  and this  temperature  and  metabolic state  of your body    and  many more factors.
 All the same factors  , which will  influence  HR  or  lactate or  MOXY values.
 Now  once I have the FTP result I can easy calculate  %  of this  one point value  and than create calculated  Zoning.
 Than the rest  is hope . I hope that   every time I do a workout   the body  will react physiologically the same otherwise  I am in trouble.. If  I  agree, that the body  will not change performance, no matter , whether I am depleted  with  glucose  or I had a   bad  night of sleep  or the temperature is  very different, than this system is  perfect.

 I f I may have  some small   doubts , that I do not feel every  day up to  the same task to reach the same average  watt  FTP , than  I  have to accept, that I may be off in  my  physiological stimulation despite being   in the same wattage  zone meaning I push the same  watt load  objectively  for a  watt load point of view.
 Okay lets' make it easier. Here  an example form two  studies . One  form Australia  and  widely published d and one  form us  small kitchen never publish  but easy to repeat  if somebody needs a paper  to  write.

heat  and  glucose.jpg 

 
Summary.. Guiding your workout  daily  with  watt feedback  has  some clear limitation to  see, whether the same watt  is really the same physiological stimulus.

Here a  second  critical  feedback  form a  study  which is  highly  accepted.
 The question, whether there is  such a  thing like a  real LT. There are  at least  20 plus  different concepts  and ideas  out there  on how  we may or may not  find a Lactate threshold. Does  that  may  ask a  question, why we  have at least 20  top research  who do not agree on  one single idea  of LT ?

 Thee  are even under this  20 + ideas three clear  trends.

 a) The once  who believe in an absolute  lactate number like  4 mmol or  another  absolute number.

b) the once  who believe in a specific  slope  of a  lactate curve    by using a tangent  or  any  model like 1 mmol   increase over at least 2  steps    or more, Using an  angle against the curve  like a 45  degree  angle  or  49.5  or  51  degree ???

 Than the MAX LASS  believer  where you have to be able to maintain a relative plateau  with some accepted  increase  over  at least 16 min or other time frames.

The MAX LASS concpet  makes  actually   lot's of sense.  and it  most liley  can be " repalced"  to ifnd   MAX LASS  by using  MOXY's  SmO2  information.

Determination of maximal lactate steady state in healthy adults: can NIRS help?

Bellotti C, Calabria E, Capelli C, Pogliaghi S.

Source

Department of Neurological, Neuropsychological, Morphological and Exercise Sciences, School of Exercise and Sport Sciences, University of Verona, Italy.

Abstract

PURPOSE:

We tested the hypothesis that the maximal lactate steady state (MLSS) can be accurately determined in healthy subjects based on measures of deoxygenated hemoglobin (deoxyHb), an index of oxygen extraction measured noninvasively by near-infrared spectroscopy (NIRS).

METHODS:

Thirty-two healthy men (mean ± SD age = 48 ± 17 yr, range = 23-74 yr) performed an incremental cycling test to exhaustion and square wave tests for MLSS determination. Cardiorespiratory variables were measured bbb and deoxyHb was monitored noninvasively on the right vastus lateralis with a quantitative NIRS device. The individual values of V˙O2 and HR corresponding to the MLSS were calculated and compared to the NIRS-derived MLSS (NIRSMLSS) that was, in turn, determined by double linear function fitting of deoxyHb during the incremental exercise.

RESULTS:

V˙O2 and HR at MLSS were 2.25 ± 0.54 L·min (76% ± 9% V˙O2max) and 133 ± 14 bpm (81% ± 7% HRmax), respectively. Muscle O2 extraction increased as a function of exercise intensity up to a deflection point, NIRSMLSS, at which V˙O2 and HR were 2.23 ± 0.59 L·min (76% ± 9% V˙O2max) and 136 ± 17 bpm (82% ± 8% HRmax), respectively. For both V˙O2 and HR, the difference of NIRSMLSS from MLSS values was not significant and the measures were highly correlated (r = 0.81 and r = 0.76). The Bland-Altman analysis confirmed a nonsignificant bias for V˙O2 and HR (-0.015 L·min and 3 bpm, respectively) and a small imprecision of 0.26 L·min and 8 bpm.

CONCLUSIONS:

A plateau in muscle O2 extraction was demonstrated in coincidence with MLSS during an incremental cycling exercise, confirming the hypothesis that this functional parameter can be accurately estimated with a quantitative NIRS device. The main advantages of NIRSMLSS over lactate-based techniques are the noninvasiveness and the time/cost efficiency.


 Now below  some more critical feedbacks  on  LT  and its  " existance
LT  most likely could be  just MAX  LASS, but   MAX LASS   may depend on duration  of the load.
 MOXY's  SmO2  is  a live steady feedback  so you can see, whethr you sustain a stable SmO2  by the same wattage or whether you have to reduce wattage to sustain a stable SmO2 trend.

 





Lactate and O2 during exercise: is lactate an anaerobic metabolite?

Numerous studies beginning with those of Pasteur (see Keilin, 1966) in the 18th century demonstrated that anoxia and hypoxia stimulate cellular HLa production. For example, in 1891, Araki (cited in Karlsson, 1971) reported elevated La levels in the blood and urine of a variety of animals subjected to hypoxia. Then, Fletcher & Hopkins (1907) found an accumulation of La in anoxia as well as after prolonged stimulation to fatigue in amphibian muscle in vitro. Subsequently, based on the work of Fletcher & Hopkins (1907) as well as his own studies, Hill et al. (1924) postulated that HLa increased during muscular exercise because of a lack of O2 for the energy requirements of the contracting muscles.

There is no disagreement that PO2 values in the range of ∼0.5 Torr or less result in O2-limited cytochrome turnover, and therefore O2-limited oxidative phosphorylation, a condition termed dysoxia (Connett et al. 1990). However, problems have arisen because of the application of the converse of this construct, i.e. that elevated HLa production and accumulation necessarily indicate the presence of dysoxia. This supposition formed the groundwork for the anaerobic threshold concept, which was introduced and detailed by Wasserman and colleagues in the 1960s and early 1970s (see Wasserman, 1984). The basic anaerobic threshold paradigm is that elevated HLa production and concentration during muscular contractions or exercise are the result of O2-limited oxidative phosphoryation. Similarly, standard medical practice has accepted an elevated blood La concentration ([La]) as the herald of O2 insufficiency (Mizock & Falk, 1992).

Over the past 35 years, considerable evidence has mounted against the idea of dysoxia as the primary cause of increased HLa production and accompanying increases in muscle and blood [La] during submaximal exercise (e.g. Connett et al. 1986) and in some clinical situations as well (see below). Recently, Richardson et al. (1998) used proton magnetic resonance spectroscopy (1H-MRS) to determine myoglobin saturation (and thereby estimate intramuscular PO2) during progressive single-leg quadriceps exercise in humans. Increasing La efflux with increasing work rate did not appear to be the result of inadequate O2 and thereby O2-limited oxidative phosphorylation. Instead, as the intramuscular PO2 (iPO2) decreases, oxidative metabolism becomes O2 dependent (see Gladden, 1996). Within some low range of iPO2 (< 20 Torr?), larger increases in [NADH]/[NAD+] and ([ADP][Pi]/[ATP]) are required to maintain adequate stimulation of cellular respiration to meet the aerobic ATP demand. The connection to increasing La production and higher muscle and blood [La] is that the requisite increase in ([ADP][Pi]/[ATP]), to compensate for the lower iPO2, is a potent stimulus of glycolysis. (For further details of this paradigm, see Connett et al. 1990; Gladden, 1996.) Accordingly, the best evidence indicates that O2 is only one of several interacting factors that cause an increase in muscle and blood [La] at submaximal exercise intensities. Additional factors are listed in Table 1 and some are discussed in detail by Gladden (2003).

 

 

Lactate efflux is unrelated to intracellular PO2 in a working red muscle in situ.

 

Connett RJ, Gayeski TE, Honig CR.

 

Abstract

 

Blood flow, lactate extraction, and tissue lactate concentration were measured in an autoperfused pure red muscle (dog gracilis). Muscles were frozen in situ during steady-twitch contraction at frequencies of 1-8 Hz [10-100% of maximum O2 consumption (VO2max)]. Myoglobin saturation was determined spectrophotometrically with subcellular spatial resolution. Intracellular PO2 (Pto2) was calculated from the oxymyoglobin-dissociation curve. Tissue lactate was well correlated with VO2 but not with Pto2. Lactate efflux increased markedly above a threshold work rate near 50% VO2max. Efflux was neither linearly correlated with tissue lactate nor related to Pto2. Pto2 exceeded the minimum PO2 for maximal VO2 in each of 2,000 cells examined in muscles frozen at 1-6 Hz. A small population of anoxic cells was found in three muscles at 8 Hz, but lactate efflux from these muscles was not greater than from six other muscles at 8 Hz. Our conclusions are that

 

1) the concept of an anaerobic threshold does not apply to red muscle and

 

2) in absence of anoxia neither tissue lactate nor blood lactate can be used to impute muscle O2 availability or glycolytic rate. A mechanism by which the blood-tissue lactate gradient could support aerobic metabolism is discussed.



Now I drifted  as usual far off. So next  up is the practical answer to show you how easy it is to use  MOXY'  and how  far  and how many different levels you can apply after you started to integrate the basic  idea of using MOXY. So stay tuned  for  a practical session on this.

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