Aller à l'échec ou pas ? (anglais)
Posté: 19/03/2004 19h21
Voila un post HYPER technique mais très intéressant, attention il faut vraiment s'accorcher, perso j'arrive pas à suivre la moitié
Pour ceux qui aurait pas le courage de lire : n'ALLER pas à l'échec trop crevant, trop taxant pour le CNS, rien de NEW, mais bcp bcp de détails techniques pour ceux que ca peut intéresser.
A :It is a factor in strength training for SHW powerlifters, because with more muscle you don't need as much muscle recruitment to lift the same weight.
B : you do know some powerlifter/strongman/olympic lift 3x or even more their own bodyweigt while not gaining in mass, wich is becaus of the correct taxing of the CNS wich allows greater reqruitment of muscle fibers (this sounds silly but check with studies done on gorilla's, they can activate 100% CNS are immensly strong)
A: I don't really doubt it, because for one, it's hard to train to real failure lifting olympically, mainly because bar speed is so important, etc.
B : Pudzianowski has never trained to failure (maybe to brag) and IS the strongest man in the world, look at his training routine some of the weights he uses are even in my range
A :This is why I said to periodize it. You can definately increase strength training to failure with high sets...
B: training to failure with high sets great way to overload the CNS and be overtraining in no time
i don't think you know what ATP levels are, when you train to failure with high reps the hyperthorphy caused to the muscle fibers aint greater becaus muscle fatigue is caused by the CNS, that is WHY I SAID THAT WHEN YOU TRAIN SHORT OF FAILLURE YOU CAN LIFT PROGRESSIVE !!!!!!!!!!!!!!!!!!!
this is from the article you should have read and then the debate would be over
...training submaximally from what has been mentioned above it would seem fair to assume that this type of training would be pretty useless unless it is performed to failure...however the difference between taking a set to failure or to 1 or even 2 reps before failure will occur seems negligible..plus by ,manipulating rest intervals shortening the amount of rest inbetween consecutibe sets intensity is increased or by increaseing the amount of time it takes to perform the repetition...training to the exact moment of failure is not neccessarily imperative...
Now this is where we start to get to the nitty gritty, but first I will have to cover some background stuff on fatigue...for this I am assuming that you have knoweldge of how energy is formed...if not let me know and I will post some info...
ATP/Pc factors: Intramuscular levels of ATP fall rapidly during exercise...this is thought to be one of the major factors in fatigue...
Creatine Phosphate levels fall rapidly at the onset of exercise, after a period of roughly 30 secs levels may be as low as 5% of the prexercise concentration. Consequenlty there wont be optimal levels of CP to replenish ATP stores.
Creatine Phosphate fuels the ADP/ ATP conversion, as levels of CP decline levels of ATP get depleted.
The ATP/PC system fuels the first few seconds of exercise...after which anaerobic glycolysis takes place... a buy product of glycolysis is Lactic acid, which casues a build-up in the muscle cells of Hydrogen ions (H+) raising the p.H.... Which affects the process that exposes actin cross-bridging sites (troponin) and permit muscle contraction. ATP formation is also affected.
calcium ions (Ca++) are released from the sarcoplasmic reticulum by the T tubules during muscle contraction and returned by the Ca-Pump.
Reduced sarcoplasmic Ca++ concentrations has been linked to fatigue. Declines in force that can be produced have been linked to declined levels of CA++ (Calcium ions). This is because decreased Ca++ released reduces the number of actin/myosin cross-bridges that can be formed. This is most likely to be due to impairement of the T-tubule. While exercising potassium ions (K+)build up in the T-tubules, this is due to the inability of the Na+K+ ATPase (breaks down ATP) Pump (sodium, potassium atpase pump) to maintain the proper Na+/K+ balance at the T-tubules. This affects the conduction of the action potential (these cause movement to occur...like an electrical impulse) to the sarcoplasmic reticulum, consequently Ca++ release is inhibited affecting one's capacity to contract a muscle. lactic acid again builds yup here and once again intracellular H+ concentrations increase, this then slows the uptake of Ca++ by the sarcoplasmic reticulum, because the H+ affects the pump. Therefore there is a marked reduction in levels of Ca++
As should be obviuos ATP is broken and provides the energy for contraction (into ADP and Pi)this inorganic phosphate (Pi) builds up. Increased Pi levels are thought to inhibit further cross-bridges being formed between the filaments. As ATP is used to fuel the muscle contraction, Pi is released from the myosin head. Increased concentrations of Pi affects this from happening.
Intensity and Failure
That being said I can now continue...HIT popularized by Mike mentzer (hope this doesnt open up the proverbial can of worms!)is based on the premise that If you don't take your sets to failure, then you are not presenting your body with the stimulus to adapt because you can perform the appropriate amount of reps. Therefore as you take your reps to failure, you are presenting the stimulus by forcing your body to cope with something that it cannot do (remeber the original post!). Consequently you adapt because you have forced yourself to do something that it simply cannot do...seems logical and simple right! But you have to ask yourself, why are so many powerlifters muscular if they dont train to failure? as with olympic lifters!
...I take you back to the theory of rate coding..essentially you fail in an exercise because there are not sufficiently rested muscle fibres to perform the task...at the end of the set the only fibres that arent fatigued are the low threshold high endurance motor units..which dont have the neccessary force producing capabilities to perform the work.
I take you back now to the theory of supercompensation and the subesequent breakdown and buildup theory that dictates that muscle damage (catabolism) has to occur for the increase in proetin synthesis to occur!...
...Research has shown that the most muscle damage occurs during the negative paotion of the exercise (sarcomere popping!)...this is because less muscle fibres are recruited to perform the eccentric movemnt resulting in a greater stress on those fibres...consequently by increasing the time that the muscle fibres are under tension (most tension is generated during -ve portion) there in theory is a better stimulus for muscle growth! ... from this it seems that more tension can be generated by taking a set to failure than stopping short because it would take longer to perform! keep this in mind!
...Back to rate coding (seems pretty important doesnt it?) as the moment of failure draws closer the CNS will innervate all the motor units it can to perform the reps and fire them as often as it can...however as fatigue sets in there is a reduction in firing frequency (up to around 70-80% I think!), consequently the rate of twitching is not high enough to continue the exercise...thus failure occurs.
...back to neural factors...as a nueron fires it has to release the neurotransmitter Acetyl Choline so that the message can be carried...as mentioned previoulsy the electrical current is passed down the axon due to the na+ and K+ (when people refer to electrolites in sports drinks like gatorad, lucozade, these is what they are refering to), and the K+ Na+ atp ase pump... as failure approaches (lack of firing) the electrolites become taxed...as failure occurs these are virtually depleted...it is speculated that another of the major factors in fatigue is the inability of the motor neurons to create and release acetylcholine (ACh) fast enough so that transmission of the action potential can be maintained from the neron to the muscle...
It can be said that ability to produce force is dependant on power speed and frequency of the 'electrical impulse elicited by the CNS to contract a muscle...as fatigue develops there is a mared decrease in the speed of these signals, as this occurs inhibitory mechanisms (mentioned previuos) stop further contrcations occuring....
...However due to emotional factors lke psyching oneself up it is possible to extend the time until these inhibitory mechanisms take effect(fight or flight syndrome)...there is a ditinct relationship between this and catecholamine levels...
...Therfore I hope that you can see that failure may not occur due to the peripheral (muscle) factors but the Central ones...failure may not be due to muscular fatigue but neural inhibition...the CNS does this for one simple reason: SO THAT IT CAN REST AND RECOVER
...If we are to believe the supercompensation theory muscle fibers need to produce appropriate tension for a long enough period of time to cause damage breakdown...this has the effect of growth factors to be released in the cells Calcium levels within the cell must increase toperpetuate both Catabolism and the required anabolic effect. Growth stimuli may also be provided by the fatigue metabolites building up (phosphate and hydrogen ions) due to elevated levels of lactic acid . Please not that any of these reactions occurs because of muscular failure!
It may become evident that failure is actaully detrimental (note to John this would neccessiate the two factor theory, that has always been rejected by bodybuilders) because too much stress occurs (especially if inadequate rest intervals are used)...this would facilitate the increasing levels of fatigue resulting in a faster establishment of the Overtraining syndrome!"
Pour ceux qui aurait pas le courage de lire : n'ALLER pas à l'échec trop crevant, trop taxant pour le CNS, rien de NEW, mais bcp bcp de détails techniques pour ceux que ca peut intéresser.
A :It is a factor in strength training for SHW powerlifters, because with more muscle you don't need as much muscle recruitment to lift the same weight.
B : you do know some powerlifter/strongman/olympic lift 3x or even more their own bodyweigt while not gaining in mass, wich is becaus of the correct taxing of the CNS wich allows greater reqruitment of muscle fibers (this sounds silly but check with studies done on gorilla's, they can activate 100% CNS are immensly strong)
A: I don't really doubt it, because for one, it's hard to train to real failure lifting olympically, mainly because bar speed is so important, etc.
B : Pudzianowski has never trained to failure (maybe to brag) and IS the strongest man in the world, look at his training routine some of the weights he uses are even in my range
A :This is why I said to periodize it. You can definately increase strength training to failure with high sets...
B: training to failure with high sets great way to overload the CNS and be overtraining in no time
i don't think you know what ATP levels are, when you train to failure with high reps the hyperthorphy caused to the muscle fibers aint greater becaus muscle fatigue is caused by the CNS, that is WHY I SAID THAT WHEN YOU TRAIN SHORT OF FAILLURE YOU CAN LIFT PROGRESSIVE !!!!!!!!!!!!!!!!!!!
this is from the article you should have read and then the debate would be over
...training submaximally from what has been mentioned above it would seem fair to assume that this type of training would be pretty useless unless it is performed to failure...however the difference between taking a set to failure or to 1 or even 2 reps before failure will occur seems negligible..plus by ,manipulating rest intervals shortening the amount of rest inbetween consecutibe sets intensity is increased or by increaseing the amount of time it takes to perform the repetition...training to the exact moment of failure is not neccessarily imperative...
Now this is where we start to get to the nitty gritty, but first I will have to cover some background stuff on fatigue...for this I am assuming that you have knoweldge of how energy is formed...if not let me know and I will post some info...
ATP/Pc factors: Intramuscular levels of ATP fall rapidly during exercise...this is thought to be one of the major factors in fatigue...
Creatine Phosphate levels fall rapidly at the onset of exercise, after a period of roughly 30 secs levels may be as low as 5% of the prexercise concentration. Consequenlty there wont be optimal levels of CP to replenish ATP stores.
Creatine Phosphate fuels the ADP/ ATP conversion, as levels of CP decline levels of ATP get depleted.
The ATP/PC system fuels the first few seconds of exercise...after which anaerobic glycolysis takes place... a buy product of glycolysis is Lactic acid, which casues a build-up in the muscle cells of Hydrogen ions (H+) raising the p.H.... Which affects the process that exposes actin cross-bridging sites (troponin) and permit muscle contraction. ATP formation is also affected.
calcium ions (Ca++) are released from the sarcoplasmic reticulum by the T tubules during muscle contraction and returned by the Ca-Pump.
Reduced sarcoplasmic Ca++ concentrations has been linked to fatigue. Declines in force that can be produced have been linked to declined levels of CA++ (Calcium ions). This is because decreased Ca++ released reduces the number of actin/myosin cross-bridges that can be formed. This is most likely to be due to impairement of the T-tubule. While exercising potassium ions (K+)build up in the T-tubules, this is due to the inability of the Na+K+ ATPase (breaks down ATP) Pump (sodium, potassium atpase pump) to maintain the proper Na+/K+ balance at the T-tubules. This affects the conduction of the action potential (these cause movement to occur...like an electrical impulse) to the sarcoplasmic reticulum, consequently Ca++ release is inhibited affecting one's capacity to contract a muscle. lactic acid again builds yup here and once again intracellular H+ concentrations increase, this then slows the uptake of Ca++ by the sarcoplasmic reticulum, because the H+ affects the pump. Therefore there is a marked reduction in levels of Ca++
As should be obviuos ATP is broken and provides the energy for contraction (into ADP and Pi)this inorganic phosphate (Pi) builds up. Increased Pi levels are thought to inhibit further cross-bridges being formed between the filaments. As ATP is used to fuel the muscle contraction, Pi is released from the myosin head. Increased concentrations of Pi affects this from happening.
Intensity and Failure
That being said I can now continue...HIT popularized by Mike mentzer (hope this doesnt open up the proverbial can of worms!)is based on the premise that If you don't take your sets to failure, then you are not presenting your body with the stimulus to adapt because you can perform the appropriate amount of reps. Therefore as you take your reps to failure, you are presenting the stimulus by forcing your body to cope with something that it cannot do (remeber the original post!). Consequently you adapt because you have forced yourself to do something that it simply cannot do...seems logical and simple right! But you have to ask yourself, why are so many powerlifters muscular if they dont train to failure? as with olympic lifters!
...I take you back to the theory of rate coding..essentially you fail in an exercise because there are not sufficiently rested muscle fibres to perform the task...at the end of the set the only fibres that arent fatigued are the low threshold high endurance motor units..which dont have the neccessary force producing capabilities to perform the work.
I take you back now to the theory of supercompensation and the subesequent breakdown and buildup theory that dictates that muscle damage (catabolism) has to occur for the increase in proetin synthesis to occur!...
...Research has shown that the most muscle damage occurs during the negative paotion of the exercise (sarcomere popping!)...this is because less muscle fibres are recruited to perform the eccentric movemnt resulting in a greater stress on those fibres...consequently by increasing the time that the muscle fibres are under tension (most tension is generated during -ve portion) there in theory is a better stimulus for muscle growth! ... from this it seems that more tension can be generated by taking a set to failure than stopping short because it would take longer to perform! keep this in mind!
...Back to rate coding (seems pretty important doesnt it?) as the moment of failure draws closer the CNS will innervate all the motor units it can to perform the reps and fire them as often as it can...however as fatigue sets in there is a reduction in firing frequency (up to around 70-80% I think!), consequently the rate of twitching is not high enough to continue the exercise...thus failure occurs.
...back to neural factors...as a nueron fires it has to release the neurotransmitter Acetyl Choline so that the message can be carried...as mentioned previoulsy the electrical current is passed down the axon due to the na+ and K+ (when people refer to electrolites in sports drinks like gatorad, lucozade, these is what they are refering to), and the K+ Na+ atp ase pump... as failure approaches (lack of firing) the electrolites become taxed...as failure occurs these are virtually depleted...it is speculated that another of the major factors in fatigue is the inability of the motor neurons to create and release acetylcholine (ACh) fast enough so that transmission of the action potential can be maintained from the neron to the muscle...
It can be said that ability to produce force is dependant on power speed and frequency of the 'electrical impulse elicited by the CNS to contract a muscle...as fatigue develops there is a mared decrease in the speed of these signals, as this occurs inhibitory mechanisms (mentioned previuos) stop further contrcations occuring....
...However due to emotional factors lke psyching oneself up it is possible to extend the time until these inhibitory mechanisms take effect(fight or flight syndrome)...there is a ditinct relationship between this and catecholamine levels...
...Therfore I hope that you can see that failure may not occur due to the peripheral (muscle) factors but the Central ones...failure may not be due to muscular fatigue but neural inhibition...the CNS does this for one simple reason: SO THAT IT CAN REST AND RECOVER
...If we are to believe the supercompensation theory muscle fibers need to produce appropriate tension for a long enough period of time to cause damage breakdown...this has the effect of growth factors to be released in the cells Calcium levels within the cell must increase toperpetuate both Catabolism and the required anabolic effect. Growth stimuli may also be provided by the fatigue metabolites building up (phosphate and hydrogen ions) due to elevated levels of lactic acid . Please not that any of these reactions occurs because of muscular failure!
It may become evident that failure is actaully detrimental (note to John this would neccessiate the two factor theory, that has always been rejected by bodybuilders) because too much stress occurs (especially if inadequate rest intervals are used)...this would facilitate the increasing levels of fatigue resulting in a faster establishment of the Overtraining syndrome!"