[quote]Tube wrote:
<<< I for one know that I’m not working my chest any harder by going to failure on the bench press, because my shoulders take over becuase the load is too heavy.[/quote]
Then you were already beyond failure for that set.
I used to be a member of the “you must train to failure on every set” crowd. Then I became a member of the “you should rarely train to failure” crowd, the crowd that demonizes failure training.
Now, I’ve somewhat come full circle. You don’t always have to train to failure, but there is nothing wrong with doing so, and sometimes might even be necessary. What changed my mind? The following from Thibs:
"T-Nation: Okay, we’re also told by many experts never to train to failure, but again, most top bodybuilders train to failure. Is this a testament to their great genetics and drug use, or are we normal folks missing something here by avoiding failure training?
Thibaudeau: I’ll take the easy way out with this one! I’m working on a new book that will be called High-Threshold Muscle Building and there’s a section on training to failure. I’m gonna draw from it to give the readers a more complete answer… and to get the word out about the book!
From the upcoming High-Threshold Muscle Building:
Few concepts in the world of strength training have been more hotly debated than the need (or not) to reach muscle failure during your sets. Is it necessary for muscle growth? No, however I feel that it’s necessary for optimal growth.
Some argue that training to failure is either dangerous or can lead to CNS fatigue. Others argue that training to failure too often will cause an excessive amount of muscle damage and can lead to localized overtraining. I think that some of these misconceptions stem from the fact that muscle failure isn’t well understood.
The biggest proponents of training to failure have defined it as “creating a maximum amount of inroads to the muscle on each set.” This is fine and well. However, am I the only one who doesn’t understand what they mean by that? So I feel that it’s important to correctly describe what muscle failure is and why it happens. This information will allow us to make an objective assessment of the need (or not) of training to failure.
What is the Point of Failure?
Failure is actually not complicated to understand. It’s simply the incapacity to maintain the required amount of force output for a specific task (Edwards 1981, Davis 1996). In other words, at some point during your set, completing repetitions will become more and more arduous until you’re finally unable to produce the required amount of force to complete a repetition. This is muscle failure. Failure isn’t the amount of “inroad” to the muscle; it’s nothing esoteric as we just saw.
The Causes of Failure
If the concept of training to failure is actually quite easy to grasp, the causes underlying this occurrence are a bit more complex. There’s no exclusive cause of training failure, rather there are quite a few of them.
- Central/Neuromuscular Factors: The nervous system is the boss! It’s the CNS that recruits the motor-units involved in the movement, sets their firing rate, and ensures proper intra and intermuscular coordination.
Central fatigue can contribute to muscle failure, especially the depletion of the neurotransmitters dopamine and acetylcholine. A decrease in acetylcholine levels is associated with a decrease in the efficiency of the neuromuscular transmission. In other words, when acetylcholine levels are low, it’s harder for your CNS to recruit motor-units and thus you’re unable to produce a high level of force output.
- Psychological Factors: The perception of exhaustion or exercise discomfort can lead to the premature ending of a set. This is especially true of beginners who aren’t accustomed to the pain of training intensely.
Subconsciously (or not), the individual will decrease his force production as the set becomes uncomfortable. This is obviously not an “acceptable” cause of failure in the intermediate or advanced trainees, but beginners who are not used to intense training could slowly break into it by gradually increasing their pain tolerance.
- Metabolic and Mechanical Factors: It’s well known that an increase in blood acidity reduces the magnitude of the neural drive as well as the whole neuromuscular process. Lactic acid and lactate are sometimes thought to be the cause of this acidification of the blood, but this is actually not the case. The real culprit is hydrogen.
Hydrogen ions can increase blood acidity, inhibits the PFK enzyme (reducing the capacity to produce energy from glucose), interferes with the formation of the actin-myosin cross bridges (necessary for muscle contraction to occur), and decrease the sensitivity of the troponin to calcium ions.
Potassium ions can also play a role in muscle fatigue during a set. Sejersted (2000) has demonstrated that intense physical activity markedly increases extra-cellular levels of potassium ions. Potassium accumulation outside the muscle cell leads to a dramatic loss of force which obviously makes muscle action more difficult.
Finally we can include phosphate molecules into the equation. Phosphate is a by-product of the breakdown of ATP to produce energy. An accumulation of phosphate decreases the sensitivity of the sarcoplasmic reticulum to calcium ions. Without going into too much detail, this desensitization reduces the capacity to produce a decent muscle contraction.
- Energetic Factors: Muscle contraction requires energy. Strength training relies first and foremost on the use of glucose/glycogen for fuel with the phosphagen system (ATP-CP) also playing a role.
Intramuscular glycogen levels (glucose reserve in the muscle) is very limited and can become depleted as the training session progresses. The body can compensate by mobilizing glucose stored elsewhere in the body (but this amount is also finite), by transforming amino acids into glucose (which is a less powerful way of producing energy for intense muscle contractions) or turn to free fatty acids and ketone bodies.
The last two solutions can’t provide energy as fast as intramuscular glycogen can. As a result, even though it will be possible to continue exercising with a depleted muscle, it’s impossible to maintain the same level of intensity and force production.
So as you can see, it’s impossible to attribute muscle failure to a single phenomenon. Rather, it’s a mix of several factors that cause muscle failure. Contrary to popular beliefs, reaching muscle failure in one set doesn’t ensure the complete fatigue and stimulation of all the muscle fibers in a muscle. Far from it!
Failure can occur way before full contractile fatigue has been reached. This means that the “one set per exercise to failure” method isn’t ideal for maximal growth. As a part of a more complex training plan it can be beneficial from time to time, but not as a discrete training system.
At some point it becomes necessary to increase training volume to fully stimulate a larger pool of muscle fibers. Remember that simply recruiting a motor-unit doesn’t mean that it’s been stimulated. To be stimulated a muscle fiber must be recruited andfatigued (Zatsiorsky 1996).
If training to failure doesn’t ensure full motor-unit stimulation within a muscle, not taking a set to positive muscle failure (the point where a technically correct full repetition can’t be completed) is even less effective since it won’t fatigue the HTMUs as much. And remember that a muscle fiber that isn’t fatigued isn’t fully stimulated! In other words, training to failure doesn’t guarantee maximal motor-unit stimulation, but not taking a set to failure drastically reduces the efficacy of a set.
This indicates that high volume of work without going to failure isn’t ideal for maximal muscle growth (but it’s okay for strength and power oriented training). But at the other end of the spectrum, low-volume training taken to failure isn’t ideal either. Failure and volume are both needed for maximal motor-unit stimulation. That’s not to say that you should use a huge volume of work, but a moderate volume of sets taken to failure is necessary for maximal muscle growth.
And what about the so-called CNS drain that can occur when you take your sets to failure? I do agree that for continuous improvements to occur one should avoid CNS burnout/overtraining (also called the Central Fatigue Syndrome). And I understand the theory behind avoiding going to failure: going to failure increases the implication of the nervous system because as fatigue sets in (accumulation of metabolites and energetic depletion) it must work harder to recruit the last HTMUs.
The argument is that we should minimize training that has a high demand on the nervous system. However, most people who espouse the “don’t go to failure” theory are generally proponents of heavy lifting and/or explosive lifting, both of which are just as demanding (if not more) on the nervous system as training to failure. Why are they against one neural intensive method but for another one?
The fact is that the CNS is an adaptive system just like the rest of our body and it can become more efficient at stimulating muscle contraction when it’s trained properly. And while CFS is a real problem, its occurrence in bodybuilders or individuals training for muscle mass gains is minimal, close to nil in fact.
Sure, we can suffer from CNS fatigue after a training session (just like our muscles are fatigued too), but the body can recover from that. Neurotransmitter depletion might be a concern, but rarely is a real problem. Using a supplement like Biotest’s Power Drive can help in that regard by boosting acetylcholine and dopamine levels.
Key Points
-
Muscle failure isn’t an indication that every muscle fiber within a muscle has been fully stimulated. However, going to failure will make sure that you’re getting the most out of that set.
-
Muscle failure can occur because of neural, psychological, metabolic, or energetic factors.
-
A moderate amount of work to failure is required for full motor-unit stimulation within a muscle."
[quote]Tiribulus wrote:
Tube wrote:
<<< I for one know that I’m not working my chest any harder by going to failure on the bench press, because my shoulders take over becuase the load is too heavy.
Then you were already beyond failure for that set.[/quote]
Right, when most coaches/athletes talk about failure, they mean technical failure. In other words when one can no longer perform the exercise using perfect form (or the same form).
If your pecs can’t lift the weight using the same form you’ve been using for the duration of the set, and your shoulders have to take over, you’ve already reached failure and there’s absolutely no point in grinding out a rep where your shoulders do the majority of the work (unless perhaps you’re benching to develop your shoulders).
[quote]Tiribulus wrote:
Tube wrote:
<<< I for one know that I’m not working my chest any harder by going to failure on the bench press, because my shoulders take over becuase the load is too heavy.
Then you were already beyond failure for that set.[/quote]
I disagree, failure is when you attempt the lift, but don’t successfully complete it.
[quote]blue9steel wrote:
Tiribulus wrote:
Tube wrote:
<<< I for one know that I’m not working my chest any harder by going to failure on the bench press, because my shoulders take over becuase the load is too heavy.
Then you were already beyond failure for that set.
I disagree, failure is when you attempt the lift, but don’t successfully complete it.[/quote]
The second you can no longer contract the target muscles they have “failed” simply put, as far as I’m concerned.
You may keep moving the weight through different mechanisms, but you’re at failure when the group you’re after can no longer sustain the work. Unless you’re not after a group and only care about moving the weight.
[quote]Tiribulus wrote:
You may keep moving the weight through different mechanisms, but you’re at failure when the group you’re after can no longer sustain the work. Unless you’re not after a group and only care about moving the weight.
[/quote]
That’s called “powerlifting”.
There are many schools of thought on whether or not you should train to failure. Like everything else in your arsenal why not incorporate it into your routine on a limited basis. Change is always good.
[quote]greekdawg wrote:
Tiribulus wrote:
You may keep moving the weight through different mechanisms, but you’re at failure when the group you’re after can no longer sustain the work. Unless you’re not after a group and only care about moving the weight.
That’s called “powerlifting”.[/quote]
Exactly and if your goal is to simply move as much weight as possible that’s a different story. If your goal is to stimulate growth then the set has failed when the muscles you’re trying to stimulate no longer can be effectively.
[quote]blueknight wrote:
There are many schools of thought on whether or not you should train to failure. Like everything else in your arsenal why not incorporate it into your routine on a limited basis. Change is always good.[/quote]
Indeed, as there are differences in the way people respond to it. Some do well never using it and some do well using it often.
[quote]derek wrote:
DC Training, which seems to be an extraordinarily effecient method of hypertrophy training, has the trainee perform 1 set to failure
…
[/quote]
First time I hear of DC training! Busy reading up on, and can’t believe this is the first time I hear of it - seems quite popular. Thanks for mentioning it!