Is too much volume a CNS or muscle breakdown issue?

[MaFi0s0]

Alternating exercises to allow increased PRE.

I am considering alternating excercises in order to ease the strain on the CNS while maximising muscle stimulation.

We know the longer you have been training the more volume you need and the slower you grow.

If a trainee was to use a more advanced amount of volume with the same PRE it will lead to overtraining but will this be due to CNS fatigue or too much muscle breakdown?

What I am getting at is if someone was to implement exercise variation into HST by either using an A B type full body workout or even an A B C type full body workout, should they train closer to their maxes during the week or increase the volume.

edit: I think i remember it being a muscle breakdown issue.

So increasing the amount of exercises should allow someone to hit failure each week rather than every 2nd week? has anyone tried this?

 

[Bryan Haycock]

CNS fatigue is brought on by overall physical "effort", and is not dependant on the exercise. So if you as the lifter are straining and pushing/pulling as hard as you can, reaching failure often, you will eventually overtraing (i.e. suffer from CNS fatigue).

What is your goal in adding different exercises? Is your goal to train to failure more frequently? If so, are you confident that this will lead to faster gains in muscle mass as opposed to stopping short of failure?

Or is your goal simply to add variation in exercise selection? If so, are you doing this for faster gains or to improve the workout "experience"? (i.e. less boring less mundane)

 

[jvroig]

I am considering alternating excercises in order to ease the strain on the CNS while maximising muscle stimulation.

As long you are often training to failure, you won't be avoiding straining the CNS. It isn't exercise-aware - all it knows is you are exerting more effort than it can handle, and that holds true whether it is 12 sets of one exercise or 2 sets each of 6 exercises.

We know the longer you have been training the more volume you need and the slower you grow.

Yep, RBE = Repeated Bout Effect. Since we can only increase weight and volume up to a certain degree after which it becomes physically impossible (or counter-productive due to CNS fatigue), we counter RBE as best we can using strategic deconditioning.

If a trainee was to use a more advanced amount of volume with the same PRE it will lead to overtraining but will this be due to CNS fatigue or too much muscle breakdown?

Both may happen, the main difference being one is caused by insufficent diet/rest, while the other is really mostly on not avoiding training to failure. Without sufficient diet and rest, too much muscle breakdown may happen when training sessions are too frequent/intense than can be sustained by the diet (not enough protein, maybe not enough calories at all, etc) or lack of rest/recovery time. CNS fatigue may happen if the sessions are always too intense and you are often training to failure. Traiing to failure has little benefit of itself, and is best avoided. Instead of going to failure trying to finish a set, it's better to cut the set short, rest for 3mins, then try to continue the set. Just stop short of failure.

So increasing the amount of exercises should allow someone to hit failure each week rather than every 2nd week?

As far as the CNS is concerned, effort is effort, it's all the same for it even if, for you, you are doing different exercises. Train to failure more often, increase the risk of CNS fatigue. Changing exercises won't affect it.



Short answer, taking your thread title directly: too much volume can lead to both CNS fatigue or muscle breakdown issue.

 

[jvroig]

Somehow the topic of this thread got stuck in my mind, and now I feel the need to clarify a few things, especially about training to failure.

If the OP ever gets back to read this thread, or anybody else for that matter who is interested in the topic, I think it should be stated for clarity that training to failure is not evil:

Training to failure is NOT evil

However, in the context of HST, we do not encourage training to failure. It is not evil, but it is counter-productive. To further clarify, by "in the context of HST", I mean "in the context of wanting to grow big as much as possible in the least time required".

In the context of HST (wanting to grow big ASAP), training to failure is counter-productive

Training to failure becomes counter-productive due to human limitations - primarily in our central nervous system (CNS; this is the part of the nervous system that coordinates the activities of every part of the body). Whenever you exert yourself, it strains the CNS. In this context, "strain" may be too harsh a word, and the CNS recovers by itself,anyway. You just have to give it enough time, during which it is understood your physical exertion is much less in intensity. But when you exert yourself to exhaustion, and repeatedly, the CNS is strained to the point that it will need more time to recover, and until it recovers, you just "feel poorly" since your CNS is shot - lack of motivation and poor performance are some of the common signs of CNS fatigue.

When you train at 100% of your RM, and train "intensely" to the point of failure (let's not mention other "methods" here ), you end up needing more time to recover, say a week, probably. By that time, protein synthesis has long since dropped off, we've failed to take advantage of any summation effect available to us, and most of that time our muscles, while ready to grow again, are just twiddling their thumbs. It's not their fault that we gotta recover - it's the CNS.

SAID - Specific Adaptation to Imposed Demands

In other contexts, training to failure may be helpful or even required (just not in the context of HST). In physical therapy / sports coaching / exercise physiology, there is what is known as the SAID principle, or Specific Adaptation to Imposed Demands. It states that the body will respond/adapt to whatever you challenge it with. Given biomechanical or neurological stressors, the body will specifically adapt to the imposed demands. If you train it for endurance, it'll increase its endurance, train for strength and it becomes stronger, etc.

Training to failure, if the context of endurance training, is a must, as that challenges the CNS to increase its endurance.

So when I said in my previous post that "Training to failure has little benefit of itself", I don't mean it to say that "Training to failure is completely useless and evil". I only mean it within the context of HST, which is "to grow big, ASAP". There are a ton of other athletes with goals far different than the goals of HST, and for them, training to failure may be necessary. It all depends on the goal and context.