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Juerg Feldmann

Fortiori Design LLC
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Posts: 1,530
 #1 
We have an increasing numbers of   readers understanding  our  idea  in using MOXY /NIRS to plan individual loads in workouts of shorter duration. This can be strength workouts  or  interval workouts  with body weights  and many more options of activities.
 I use this idea in my office  daily  from 80 plus year old  people down to   top trained individuals   during rehabilitation but as well   in  performance  sport. This is the way  how  Brian Kozak , the leading ice hockey conditioning coach is using MOXY  in his groups.

Now many agree , that it sounds easy  and logic  and fascinating, but they as well ask  with a healthy critical  view, whether we  are just  from another planet  or whether there are actually studies done independently  from us  who  would at least support ideas  like SmO2  recovery can be used   to  have some indirect feedback on Cr>p  recovery.
 The other   most common understandable questions is the current  still most used model  of ATP  than Cr.P  than  Glucose  and finally we  may take  O2. I   showed  somewhere in my mess this  answer  already but I like to add some additional feedback on tat changing idea  on O2  use   and high intensity work.
 So  first the question of SmO2  and Cr.P  relation. The beauty on this question  is as well as it is a  direct validation of NIRS , a question we  often are getting as well.
Oxidative phosphorylation is  one of the Key words.

A cross-validation of near-infrared spectroscopy measurements of skeletal muscle oxidative capacity with phosphorus magnetic resonance spectroscopy

Terence E. Ryan , W. Michael Southern , Mary Ann Reynolds , Kevin K. McCully

Journal of Applied Physiology Published 15 December 2013 Vol. 115 no. 12, 1757-1766 DOI: 10.1152/japplphysiol.00835.2013

 

 

Abstract

The purpose of this study was to cross-validate measurements of skeletal muscle oxidative capacity made with near-infrared spectroscopy (NIRS) measurements to those made with phosphorus magnetic resonance spectroscopy (31P-MRS). Sixteen young (age = 22.5 ± 3.0 yr), healthy individuals were tested with both 31P-MRS and NIRS during a single testing session. The recovery rate of phosphocreatine was measured inside the bore of a 3-Tesla MRI scanner, after short-duration (∼10 s) plantar flexion exercise as an index of skeletal muscle oxidative capacity. Using NIRS, the recovery rate of muscle oxygen consumption was also measured using repeated, transient arterial occlusions outside the MRI scanner, after short-duration (∼10 s) plantar flexion exercise as another index of skeletal muscle oxidative capacity. The average recovery time constant was 31.5 ± 8.5 s for phosphocreatine and 31.5 ± 8.9 s for muscle oxygen consumption for all participants (P = 0.709). 31P-MRS time constants correlated well with NIRS time constants for both channel 1 (Pearson's r = 0.88, P < 0.0001) and channel 2 (Pearson's r = 0.95, P < 0.0001). Furthermore, both 31P-MRS and NIRS exhibit good repeatability between trials (coefficient of variation = 8.1, 6.9, and 7.9% for NIRS channel 1, NIRS channel 2, and 31P-MRS, respectively). The good agreement between NIRS and 31P-MRS indexes of skeletal muscle oxidative capacity suggest that NIRS is a valid method for assessing mitochondrial function, and that direct comparisons between NIRS and 31P-MRS measurements may be possible.

 
Now  there are some interesting papers by Shulman idea that:
Here some short  inside  ideas  as fast  review

Robert G. Shulman

 

Department of Diagnostic Radiology, Yale University School of Medicine, MR Research Center, New Haven, CT

 

SHULMAN, R.G. Glycogen turnover forms lactate during exercise. Exerc. Sport Sci. Rev., Vol. 33, No. 4, pp. 157–162, 2005

 

 

 

INTRODUCTION

 

 

 

The modern age of lactate studies began approximately 20 yrs ago when George Brooks questioned the accepted findings of previous generations and proposed the Lactate Shuttle (1).

 

Early studies demonstrated that lactate accumulated when frog muscles contracted up to the point of exhaustion but

 

disappeared during recovery in the presence of oxygen. In that view, the creation of lactate by exercising muscle is caused by the deficit of oxygen.

 

 

 

However, numerous experiments by Brooks (1) and others have shown that lactate is generated during the performance of work by skeletal muscle in the presence of plentiful levels of oxygen (10). In fact, it is generated even when mitochondria are fully oxidized (10).

 

Lactate production under hypoxia and or anoxia is rather the exception than the norm (Gladden)

 

 

 

NMR studies of the oxygenation of muscle myoglobin in exercising humans showed that oxygen levels in working muscle decrease with load, but even at maximal oxygen consumption are well above the mitochondrial needs (8).

 

 No such thing like anaerobic  situations

 

 

 

The shuttling of lactate to redistribute energy led to questions about its origin, which was long assumed merely to be the result of an inadequate oxygen supply.

 

 This review is based on the understanding that lactate can shuttle energy

 

from locations where it is synthesized, such as white fibers in skeletal muscle or astroglia in brain, to other locations, such as red muscle fibers or synaptic neurons, where it can be oxidized (1). The residual reductive capacity of lactate to provide energy is not wasted by the body and its formation is not caused by a limited supply of oxygen. Lactate is not simply an unwanted by-product, but rather is purposefully synthesized during work to meet normal physiological needs.

 

 

However, the nature of that normal physiological mechanism has not been found. Now that the hypothesis postulating a deficiency of oxygen has been discarded, the reason for lactate generation to meet the energy needs of muscle and the brain requires an explanation. In this review, results from several  avenues of research on the energetics of skeletal muscle are coordinated to propose a model for lactate build-up during muscle work under well-oxygenated conditions, a build-up that drive the lactate shuttle.

And here some interesting add ons.( with more questions)

Robert G. Shulman

 

Department of Diagnostic Radiology, Yale University School of Medicine, MR Research Center, New Haven, CT

 

SHULMAN, R.G. Glycogen turnover forms lactate during exercise. Exerc. Sport Sci. Rev., Vol. 33, No. 4, pp. 157–162, 2005

 

 

 

We suggest that glycogenolytic ATP production supplies the energy for millisecond bursts. This hypothesis implies that _1 _mol·g_1 tissue of

 

glycogen subunits is consumed during each contraction to

 

refill the ATP and PCr pools. Because basal glycogen concentrations

 

of _70 _mol·g_1 tissue are not depleted even after several dozen contractions, resynthesis of glycogen must occur between twitches.

 

Without the millisecond time pressure of contractions, the ATP required for this resynthesis can be achieved via somewhat slower oxidative means.

 

Although oxidation cannot supply ATP in milliseconds, it could resynthesize glycogen in the _1-s interval between even rapid contractions. Measured rates of oxygen consumption vary, seemingly dependent on the measurement method.

 

None of the reported values reaches the rate of 1 _mol·g_1 tissue per twitch, but the fastest values measured do reach several _mol·g_1 tissue per second. Hence, it is possible that the glycogen pools, which are decreased to refill PCr and ATP in milliseconds, are replenished by the energy supplied oxidatively in the longer period, no shorter than _1 s, between contractions.

 

 

 

Evidence That Glycogen Rather Than PCr Generates ATP during Contraction

 

 

 

The conventional view of short-term muscle energetics is that PCr supplies almost all of the energy needed for a sustained burst of contractions lasting less than 10 s, after which it is replaced by glycogenolysis.

 

This view is not supported by experiments. In a recent review, Greenhaff and

 

Timmons (5) report, “It is now accepted, however, that PCr hydrolysis and lactate production do not occur in isolation, and that both are initiated rather rapidly at the onset of contraction.”



So here  an experiment  which would support the view  above.



Muscle deoxygenation in aerobic and anaerobic exercise.

 

Authors

 

Nioka S1, Moser D, Lech G, Evengelisti M, Verde T, Chance B, Kuno S.

 

Author information

 

  • 1Department of Biochemistry and Biophysics, University of Pennsylvania, USA.

    Journal

    Adv Exp Med Biol. 1998;454:63-70.

    Affiliation

    Abstract

    It has been generally accepted that the use of oxygen is a major contributor of ATP synthesis in endurance exercise but not in short sprints. In anaerobic exercise, muscle energy is thought to be initially supported by the PCr-ATP system followed by glycolysis, not through mitochondrial oxidative phosphorylation. However, in real exercise practice, we do not know how much of this notion is true when an athlete approaches his/her maximal capacity of aerobic and anaerobic exercise, such as during a graded VO2max test. This study investigates the use of oxygen in aerobic and anaerobic exercise by monitoring oxygen concentration of the vastus lateralis muscle at maximum intensity using Near Infra-red Spectroscopy (NIRS). We tested 14 sprinters from the University of Penn track team, whose competitive events are high jump, pole vault, 100 m, 200 m, 400 m, and 800 m. The Wingate anaerobic power test was performed on a cycle ergometer with 10% body weight resistance for 30 seconds. To compare oxygenation during aerobic exercise, a steady-state VO2max test with a cycle ergometer was used with 25 watt increments every 2 min. until exhaustion.

     Results showed that in the Wingate test, total power reached 774 +/- 86 watt, about 3 times greater than that in the VO2max test (270 +/- 43 watt). In the Wingate test, the deoxygenation reached approximately 80% of the established maximum value, while in the VO2max test resulted in approximately 36% deoxygenation. There was no delay in onset of deoxygenation in the Wingate test, while in the VO2max test, deoxygenation did not occur under low intensity work. The results indicate that oxygen was used from the beginning of sprint test, suggesting that the mitochondrial ATP synthesis was triggered after a surprisingly brief exercise duration. One explanation is that prior warm-up (unloaded exercise) was enough to provide the mitochondrial substrates; ADP and Pi to activate oxidative phosphorylation by the type II a and type I myocytes. In addition, transmural pressure created by the muscle contraction reduces blood flow, causing relative hypoxia.

     
     Now the fascinating part is , that it will take most often a generation of a  coach to  start looking to the next options. So  we are talking around 15 - 25 years. Not bad  , when we see Brooks  first critical reviews  on Lactate 1985.  Before that we  based all on  great work  at the time  from the early 1920 . Hill /Mayerhofer  and more great  researchers.
     Now  we have some gentle  attempt in the  exercise community to embrasse  possible  changes  due to advancing in technology. Now  already  over 10 years back there was a  shy attempt  to   try to break through with very little success as of yet.
     here to close the  day with this interesting summary
     

    Sports Med. 2001;31(10):725-41.

    Energy system interaction and relative contribution during maximal exercise.

    Gastin PB.

    Author information

    Abstract

    There are 3 distinct yet closely integrated processes that operate together to satisfy the energy requirements of muscle. The anaerobic energy system is divided into alactic and lactic components, referring to the processes involved in the splitting of the stored phosphagens, ATP and phosphocreatine (PCr), and the nonaerobic breakdown of carbohydrate to lactic acid through glycolysis. The aerobic energy system refers to the combustion of carbohydrates and fats in the presence of oxygen. The anaerobic pathways are capable of regenerating ATP at high rates yet are limited by the amount of energy that can be released in a single bout of intense exercise. In contrast, the aerobic system has an enormous capacity yet is somewhat hampered in its ability to delivery energy quickly. The focus of this review is on the interaction and relative contribution of the energy systems during single bouts of maximal exercise.

     A particular emphasis has been placed on the role of the aerobic energy system during high intensity exercise. Attempts to depict the interaction and relative contribution of the energy systems during maximal exercise first appeared in the 1960s and 1970s.

     While insightful at the time, these representations were based on calculations of anaerobic energy release that now appear questionable. Given repeated reproduction over the years, these early attempts have lead to 2 common misconceptions in the exercise science and coaching professions.

     First, that the energy systems respond to the demands of intense exercise in an almost sequential manner, and secondly, that the aerobic system responds slowly to these energy demands, thereby playing little role in determining performance over short durations.

    More recent research suggests that energy is derived from each of the energy-producing pathways during almost all exercise activities. The duration of maximal exercise at which equal contributions are derived from the anaerobic and aerobic energy systems appears to occur between 1 to 2 minutes and most probably around 75 seconds, a time that is considerably earlier than has traditionally been suggested.

     






Juerg Feldmann

Fortiori Design LLC
Registered:
Posts: 1,530
 #2 
Some great critical feed backs.
 Some very  critical  but somewhat aggressive.
 Here  just a respond  to one of them  but I  hope pother readers  can benefit  as well on these thoughts  and ideas.

1. I  do not make this ideas  up , I  have no clue on this in depth  science  and have  as most of us believe  or  at least critically read  , what is  developed  from much smarter people.
 So  when  we get challenges on what we suggest here we always try to back it up.
 Now if you have a challenge  and critical input  great but please allow me to ask  the same question back to the idea we  used or still used in the past.

  For example :
 If we  try to defend  or argue  on anaerobic workouts or anaerobic threshold.
 Nice  would be  as we  do  not have the truth here to  sent us  on here the papers  backing this ideas up, where pO2  during  a lactate threshold test   drops to 0  and ass  such can show that we really  and truly  are anaerobic.
 To avoid too much reading here  the side  of the discussion who believes and tries to proof that it is not  possible .
 

Richardson et al have concluded that: ‘‘…intracellular pO2 remains constant during graded incremental exercise in humans (50–100% of muscle VO2max)’’ so that: ‘‘With respect to the concept of the ‘‘anaerobic’’ threshold, these data demonstrate that, during incremental exercise, skeletal muscle cells do not become anaerobic as lactate levels suddenly rise, as intracellular pO2 is well preserved at a constant level, even at maximal exercise’’ (p. 63168). They also conclude that: ‘‘Net blood lactate efflux was unrelated to intracellular pO2 across the range of incremental exercise to

exhaustion’’ but was ‘‘linearly related to O2 consumption’’ (p. 62768). Another study confirmed these conclusions: ‘‘…consequently these data again demonstrate that, as assessed by cytosolic oxygenation state (deoxy-Mb) during incremental exercise, skeletal muscle cells do not become ‘‘anaerobic’’ as lactate levels rise, because intracellular PO2 is well preserved

at a low but constant level even at maximal exercise’’



So  any critical discussion  and or idea , because we like to defend  our  education ( where   as  education is the ability to repeat  what we learned , rather than the ability to challenge  what is presented ) has too be directed to this great researcher  .


 Concerning the classical ATP  CrP  glucose  and aerobe  graph we all have in our  scripts  and textbooks.
 Here again  short  where it comes  from as we had limitations in assessing this fast  metabolic reactions.

30 second studies.jpg 



Great  ability  at thee  time but  now we have some interesting progress  made. I made a  simple not optimal summary  for readers, who may not  push through hundreds  off  scientific papers. And as  so many of us  like to read the abstract or  key elements.

Glycogen Turnover Forms Lactate during

Exercise

Robert G. Shulman

Department of Diagnostic Radiology, Yale University School of Medicine, MR Research Center, New Haven, CT

SHULMAN, R.G. Glycogen turnover forms lactate during exercise. Exerc. Sport Sci. Rev., Vol. 33, No. 4, pp. 157–162,

2005. The power needs of muscle are supplied by rapid anaerobic glycogenolytic ATP generation. Lactate is built up by the mismatch

between steady state energy needs and short-term power demands and the increased concentration drives the lactate shuttle. In this

model, contributions to fatigue should be looked for in the flux of glucose through glycogen rather than in the concentrations of fuel.

Key Words: glycogenolysis, fatigue, exercise creatine kinase, lactate shuttle, skeletal muscle, acidosis

 

 

“Just how rapidly energy is obtained from PCr during single contractions was shown directly by the brilliant experiments of Chung et al. (2). Reasoning that even the fastest freeze-clamp measurements, with a time resolution of _100 ms, did not follow high-energy phosphates during contraction and relaxation, they developed a gated 31P NMR technique with _1 ms time resolution to measure phosphate metabolites in the rat gastrocnemius muscle during 1-Hz stimulation. In this experiment, the NMR pulse-acquisition sequence was triggered

synchronously with muscle stimulation and the spectra,acquired in several hundred scans, were summed. ATP remained constant at all times during contractions, whereas PCr rapidly decreased by 3 _mol·g_1 tissue per twitch with a half-time of 8 ms. PCr then recovered with a half-time of 14 ms so that the whole PCr response to a twitch was finished in _30 ms, too rapidly to have been observed by even the fastest extraction methods (Fig. 1). Chung et al. showed that this consumption of PCr/twitch is _40 times greater than the values reported by dividing the decline in PCr after several minutes of contraction by the number of twitches. This 31P NMR study showed that “the traditional method of calculating PCr/twitch underestimates the high-energy consumption arising from the drop and subsequent restoration of the PCr pool during the millisecond contraction cycles” (2). Chung et al.’s experiments show that PCr cannot be the ultimate source of energy in contracting muscle. At a cost of 3 mmol PCr/twitch, the muscle would be rapidly depleted of energy unless PCr were being replenished. The experiments show that PCr recovered between contractions.

 The question then becomes not whether PCr supports the contractions, but what source of energy replenishes the PCr levels after a contraction.

 

Although oxidation cannot supply ATP in milliseconds, it could resynthesize glycogen in the _1-s interval between

even rapid contractions. Measured rates of oxygen consumption vary, seemingly dependent on the measurement method. None of the reported values reaches the rate of 1 _mol·g_1 tissue per twitch, but the fastest values measured do reach several _mol·g_1 tissue per second. Hence, it is possible that the glycogen pools, which are decreased to refill PCr and ATP in milliseconds, are replenished by the energy supplied oxidatively in the longer period, no shorter than _1 s, between contractions”


So based on many of this great  studies  we simply try to apply them back to the grass root  user  who does not have all this toys  and   knowledge.
 MOXY is  a  new generation  of  affordable  bio feedback tools , who  will help us to improve the individual planning  in rehabilitation  and training ideas.

 We now can see live, whether you  like to load  more the utilization systems  or more the delivery system or  whether you are actually able to  deliver  O2  from the workout plan you have  or not. In simple words, you see what is happening and in many cases  it may be not  what we  where hopping for. Nut that is nothing bad isn't it.


 So what we  try  to do is  to  have  an idea  and than try to see, whether we  can achieve  the  theory   by looking   at the practical application. Here a simple example  from our  grade 10 - 12  students in  my small carrier  prep  program  form the local high school.
 We  can discuss more if there is interest  in what we  do .

smo2  thb leg hypoxic hyper cpan.jpg 
The kids  had a very specific  task .
 What was the idea or theory they had  to try to proof ?

 





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