Post by John A. Casler on Jun 14, 2008 13:54:30 GMT -8
To Fail, or not to Fail, THAT is the question.
Seems like there is much disagreement regarding the "value" of TF (To Failure) training.
It is suggested by those who "train to failure" that concentric failure is the level of stimulus required to produce maximum stimulation to a muscle or bodypart and that further stimulus is not only not needed, but will cause over stimulation or over training and negative result, regress, or overtraining.
Of course all who have trained seriously for any length of time know that the personal effort to reach the conditions that cause failure have very strong sensation of stimulus. One might think that such a huge effort cannot help but be the maximum stimulus since one literally cannot train any harder.
There is little doubt that when one trains to temporary muscle failure, that it takes a HUGE effort, and it feels quite "INTENSE" which is really the most likely cause for the term HIGH INTENSITY TRAINING.
But what advantages if any does "to failure" really have? Is failure really the "maximum stimulus"?
Tension versus Fatigue
It is know to most that study the Training Sciences that all rep schematics have an inter-relationship between Tension and Fatigue. That is if you perform "ANY" Rep Maximum effort, the limiting factor is fatigue.
The difference between a 1RM and a 2RM is fatigue. Same with the difference between a 10RM and 15RM.
So the question is how does the fatigue affect the set, and the stimulus package?
When we begin a set of reps, unless it is a 1RM the first reps are "underloaded". This means that they are not affected by fatigue at this point and their ability is higher in the area of creating force. This means they can create the greatest tensions "early" and as fatigue set in, on each succeeding rep the muscle(s) have less and less force creation potential.
Now while the reps feel like they are creating more and more tension, this is not true. The final rep of each set is the one that creates the LEAST muscle tension, to the point that if you train to failure, the final failing rep cannot create enough tension to overcome the force presented to it.
This is an important realization in analyzing the stimulus package and how it can cause stimulus and overload to the target musculature.
So why does the force ability wane? Fatigue.
From the very first rep, metabolic and neural chemical processes begin to occur. Each time these processes occur, they leave residual metabolites, and they degrade future (immediate) processes. Additionally the body functions on an "as needed" basis for most of its actions, functions and processes. Due to this type of regulation the Muscle Fibers arranged in Motor Units (MU's) are recruited in a "sparing" fashion. That is they are used according to their most efficient function.
In the case of weight training the recruitment is prioritized according to "Intensity or Magnitude of Effort", with low effort recruiting low force but enduring Type I fibers, (named Type I because they are the "1st" fibers to be recruited)
Type I fibers are not as good at force production , but have endurance and for low level loads offer longer term low tension ability.
Type II fibers are less enduring, higher in force, and recruited only when the force demands cannot be met by the Type I's.
So now we have a sense and control, and or a volitional control system that allows us to create force based on the short and long term needs during a set.
So what do we want to do?
Goals of Training: Strength vs. Hypertrophy and Tension versus Fatigue
First we need to understand that two of the most distinct stimuli are Tension, and Fatigue. Each play a role in developing and strengthening muscles.
In a Nutshell High Tensions stimulate thicker and stronger fibers via adaptive protein synthesis of the fibers and "thickening" of their structures. This is called "sarcomere hypertrophy" or thickening of the contractile structures.
Fatigue levels and metabolites tend to favor sarcoplasmic hypertrophy, or growth and increase to the systems that operate, supply, and support the muscle, but this also includes the internal structures to the muscle fibers.
Neither will occur totally without the other, but tension favors hypertrophy of the sarcomeres, and fatigue favors the sarcoplasmic increases.
To make things more complex, each of us has a genetic tendency to "respond" within a framework of these two stimuli (tension/fatigue) and much of that response is based on our muscle fiber ratios. But nothing is ever simple, and not even do all our muscles have the same ratio's. They vary depending on use, genetics and function.
Additionally there are even more factors like "hormonal profiles" and muscle shapes, that make this even more of a jigsaw puzzle to work with.
And if that wasn't complex enough, we have life stages that will affect the anabolic balances of when we grow and atrophy.
One more thing, we also have to make sure and space the stimuli apart well enough to allow for high levels of stimulations and resulting tissue damage, and the recovery and restructuring periods and nutrients to cause adaptive progress. These recovery periods will vary depending on many elements too.
So now we are back to the HIT Mantra of TO FAILURE as being the absolute in muscle and strength stimulus.
The Set of 8-12 reps taken to momentary concentric failure then is based on the "fatigue" stimulus model and is loaded slightly more toward hypertrophy and less for strength. (since there are other models that offer far higher tensions)
Now if it is performed as "commonly" suggested and the first reps are "intentionally of low effort" to attempt to inject the warm up reps and the training reps in the same set, then we have additional reduction in the stimulus tensions, and can only rely on the tension stimulus for the closing reps (which as mentioned earlier have less tension potential since fatigue reduces it) and so the STF model has limitations.
The limitations are offset slightly by intentionally upping the intensity of the closing reps till failure, assuring that the fatigue levels are high and the tension of those last reps is at its highest level, although that is well below that of fresh unfatigued reps.
So how does this compare with a "Multiple Set Model" that can employ a warm up set, that allow the succeeding sets to be attempted at "full and high effort" from the very first rep, which allows for the highest tension levels of any type of training. As well, a set can also be included that creates far more fatigue than what can be known in a Single Set. Even the "accumulative" fatigue of two or more sets can also be at a higher level, than that of a single set.
And it can easily be seen that in this scenario we have the potential to have both HIGH Tension and HIGH Fatigue being addressed in two or more different sets with the only cost being additional gym or training time.
The significant advantage of the SSTF model is that it is highly efficient. It will in the beginner and intermediate trainee produce a very high percentage of the Multiple Set models with at least 1/2 the time.
However, in its simplest and most commonly suggested form, it cannot match Multi-Set Training for the maximum result in the long term.
The belief that it can, has not been supported in the literature, nor by any long term, high level empirical evidence.
This DOES NOT suggest that remarkable results cannot be achived with this model, for they can. This is also not an indictment of the SSTF Model since it has significant value in the compensation to time spent training element, (it IS the most efficient) but those who would suggest that it even begins to approach the Multiple Set Model at the higher, more advanced and competitive levels are either unaware, uninformed, or choose to ignore the overwhelming evidence to the contrary. If the truth be known, many state they are training with a SSTF model, but in fact use the term to apply to Multiple Set To Failure programs that even include accessory stimuli in the form of Set Extensions and even Multiples of the same Exercise to Failure or NTF.
Seems like there is much disagreement regarding the "value" of TF (To Failure) training.
It is suggested by those who "train to failure" that concentric failure is the level of stimulus required to produce maximum stimulation to a muscle or bodypart and that further stimulus is not only not needed, but will cause over stimulation or over training and negative result, regress, or overtraining.
Of course all who have trained seriously for any length of time know that the personal effort to reach the conditions that cause failure have very strong sensation of stimulus. One might think that such a huge effort cannot help but be the maximum stimulus since one literally cannot train any harder.
There is little doubt that when one trains to temporary muscle failure, that it takes a HUGE effort, and it feels quite "INTENSE" which is really the most likely cause for the term HIGH INTENSITY TRAINING.
But what advantages if any does "to failure" really have? Is failure really the "maximum stimulus"?
Tension versus Fatigue
It is know to most that study the Training Sciences that all rep schematics have an inter-relationship between Tension and Fatigue. That is if you perform "ANY" Rep Maximum effort, the limiting factor is fatigue.
The difference between a 1RM and a 2RM is fatigue. Same with the difference between a 10RM and 15RM.
So the question is how does the fatigue affect the set, and the stimulus package?
When we begin a set of reps, unless it is a 1RM the first reps are "underloaded". This means that they are not affected by fatigue at this point and their ability is higher in the area of creating force. This means they can create the greatest tensions "early" and as fatigue set in, on each succeeding rep the muscle(s) have less and less force creation potential.
Now while the reps feel like they are creating more and more tension, this is not true. The final rep of each set is the one that creates the LEAST muscle tension, to the point that if you train to failure, the final failing rep cannot create enough tension to overcome the force presented to it.
This is an important realization in analyzing the stimulus package and how it can cause stimulus and overload to the target musculature.
So why does the force ability wane? Fatigue.
From the very first rep, metabolic and neural chemical processes begin to occur. Each time these processes occur, they leave residual metabolites, and they degrade future (immediate) processes. Additionally the body functions on an "as needed" basis for most of its actions, functions and processes. Due to this type of regulation the Muscle Fibers arranged in Motor Units (MU's) are recruited in a "sparing" fashion. That is they are used according to their most efficient function.
In the case of weight training the recruitment is prioritized according to "Intensity or Magnitude of Effort", with low effort recruiting low force but enduring Type I fibers, (named Type I because they are the "1st" fibers to be recruited)
Type I fibers are not as good at force production , but have endurance and for low level loads offer longer term low tension ability.
Type II fibers are less enduring, higher in force, and recruited only when the force demands cannot be met by the Type I's.
So now we have a sense and control, and or a volitional control system that allows us to create force based on the short and long term needs during a set.
So what do we want to do?
Goals of Training: Strength vs. Hypertrophy and Tension versus Fatigue
First we need to understand that two of the most distinct stimuli are Tension, and Fatigue. Each play a role in developing and strengthening muscles.
In a Nutshell High Tensions stimulate thicker and stronger fibers via adaptive protein synthesis of the fibers and "thickening" of their structures. This is called "sarcomere hypertrophy" or thickening of the contractile structures.
Fatigue levels and metabolites tend to favor sarcoplasmic hypertrophy, or growth and increase to the systems that operate, supply, and support the muscle, but this also includes the internal structures to the muscle fibers.
Neither will occur totally without the other, but tension favors hypertrophy of the sarcomeres, and fatigue favors the sarcoplasmic increases.
To make things more complex, each of us has a genetic tendency to "respond" within a framework of these two stimuli (tension/fatigue) and much of that response is based on our muscle fiber ratios. But nothing is ever simple, and not even do all our muscles have the same ratio's. They vary depending on use, genetics and function.
Additionally there are even more factors like "hormonal profiles" and muscle shapes, that make this even more of a jigsaw puzzle to work with.
And if that wasn't complex enough, we have life stages that will affect the anabolic balances of when we grow and atrophy.
One more thing, we also have to make sure and space the stimuli apart well enough to allow for high levels of stimulations and resulting tissue damage, and the recovery and restructuring periods and nutrients to cause adaptive progress. These recovery periods will vary depending on many elements too.
So now we are back to the HIT Mantra of TO FAILURE as being the absolute in muscle and strength stimulus.
The Set of 8-12 reps taken to momentary concentric failure then is based on the "fatigue" stimulus model and is loaded slightly more toward hypertrophy and less for strength. (since there are other models that offer far higher tensions)
Now if it is performed as "commonly" suggested and the first reps are "intentionally of low effort" to attempt to inject the warm up reps and the training reps in the same set, then we have additional reduction in the stimulus tensions, and can only rely on the tension stimulus for the closing reps (which as mentioned earlier have less tension potential since fatigue reduces it) and so the STF model has limitations.
The limitations are offset slightly by intentionally upping the intensity of the closing reps till failure, assuring that the fatigue levels are high and the tension of those last reps is at its highest level, although that is well below that of fresh unfatigued reps.
So how does this compare with a "Multiple Set Model" that can employ a warm up set, that allow the succeeding sets to be attempted at "full and high effort" from the very first rep, which allows for the highest tension levels of any type of training. As well, a set can also be included that creates far more fatigue than what can be known in a Single Set. Even the "accumulative" fatigue of two or more sets can also be at a higher level, than that of a single set.
And it can easily be seen that in this scenario we have the potential to have both HIGH Tension and HIGH Fatigue being addressed in two or more different sets with the only cost being additional gym or training time.
The significant advantage of the SSTF model is that it is highly efficient. It will in the beginner and intermediate trainee produce a very high percentage of the Multiple Set models with at least 1/2 the time.
However, in its simplest and most commonly suggested form, it cannot match Multi-Set Training for the maximum result in the long term.
The belief that it can, has not been supported in the literature, nor by any long term, high level empirical evidence.
This DOES NOT suggest that remarkable results cannot be achived with this model, for they can. This is also not an indictment of the SSTF Model since it has significant value in the compensation to time spent training element, (it IS the most efficient) but those who would suggest that it even begins to approach the Multiple Set Model at the higher, more advanced and competitive levels are either unaware, uninformed, or choose to ignore the overwhelming evidence to the contrary. If the truth be known, many state they are training with a SSTF model, but in fact use the term to apply to Multiple Set To Failure programs that even include accessory stimuli in the form of Set Extensions and even Multiples of the same Exercise to Failure or NTF.