T Nation

Muscles can grow without rest?

To what extent, if any, do you agree with this statement which was made by Bryan Haycock:

“Recovery issues are about the CNS. A muscle will grow with a CONSTANT load applied without any kind of break or rest or unloading.”

he adds:

“All of the strategies that we use to accommodate the limitations of our CNS are just that, ways of accommodating the limitations of the CNS. Don’t confuse them with the actual stimulus and pathways that cause the tissue to hypertrophy.”

Any thoughts?


I remember reading something similar by Jeff Everson. If I recall, he was trying to make the point that people shouldn’t be so concerned with over-training (this was during the heavy-duty craze) because muscle grows in response to the amount of stress imposed on it. He cited some study that showed that constant electrical stimulation in frogs led to increased growth even in the absence of adequate nutrients and rest (I think). I don’t remember being very convinced…

But let us suppose this is true, how would we apply this knowledge? How do you train your muscles without involving the CNS?

it all depends on the amount of breakdown that occurs. I believe with what Big L wrote that excessive breakdown from heavy negatives that recruit a lot of muscle fibers will take many days to recover. Of course muscle can be retrained if it is not broken down to a big extent. laters pk

Westsiders do this all the time.
Along with the 4 main workouts, David Tate and the boys will do extra workouts all throughout the week. The extra work is not fatiguing towards the CNS. It would involve mostly high-rep workout not to failure and/or light sled dragging…


It’s a matter of optimal growth, not just growth. Sure, we can train every day, and if we have no CNS fatigue the muscle can grow… albeit at a slower rate than if we had rested. Clearly it’s also impractical to train each muscle every day…

I can’t imagine how muscle growth could occur in the basence of nutrients.


I believe that muscles can grow under constant stress but are constrained by CNS fatigue and protien synthesis. Protien synthesis will usually stop within 36 to 48 hours after a muscle is worked which would lead one to think in terms of more frequency. CNS fatigue is a factor of load, frequency and intensity. Therefore, Haycock maintains that maximum muscle hypertrophy (but not necessarily strength to the same degree) will occur with frequent but not intensive (i.e., not going to failure and limiting the number of sets) workouts. The only time-practical way to accomplish this is to do full body workouts 3 or 4 times per week or a workout split, for instance, into push vs. pull 6 days per week. That along with strategic deconditioning every 4 to 8 weeks prevents the body’s muscles from adapting to a specific load and to allow for continued growth. That doesn’t mean that other workout schemes won’t work. It just that you have to constantly switch things up and rest your body periodically or risk stagnation. Haycock has not reinvented the wheel but merely matched up the science known to date with the experience of body builders over the last century.

They may be able to Grow without rest…But How will they perform long term…If you don’t allow them to recuperate from strenuous excercise or if you have DOMS how much positive effort could you really train with?

They may be able to Grow without rest…But How will they perform long term…If you don’t allow them to recuperate from strenuous excercise or if you have DOMS how much positive effort could you really train with?

Red, that is a theoretically good question but one that has never been tested emperically since it is not practical to have a muscle under CONSTANT tension except in a laboratory environment. Under Haycock’s protocol, you do allow for rest. However, you do not need a whole week of rest because of the lower intensity and volume. As for DOMS, unless you have actually caused more damage than mere microtrauma, which then would be more than DOMS, you can still exercise and grow. In fact, it has been shown that working thru microtrauma is better for ‘hypertrophy’ than waiting for DOMS to completely vanish. Sources behind these independent studies can be found on Haycock’s website as well as other research sites. I do not believe that it is possible for the average advanced lifter to approach his genetic potential without having a basic understanding of why muscles grow so that he may adapt training principles to his own unique situation. After 45 years of lifting, I still haven’t hit that plateau which means I still have a lot to learn.

Brian’s principles are based on the fact that the trainee is not training to failure, or at a very intense range(based on %1RM), at every workout. For instance, if your 8RM in the squat is 200lbs and your 1RM is 275, then the 8RM is about 75%1RM. In a typical HST program, you would use the following weights in your workouts: wkt.1- 130lbs, wkt.2- 145lbs, wkt.3- 160lbs, wkt.4- 175lbs, wkt.5- 190lbs, wkt.6- 205. The average weight of the six workouts is 167.5lbs. This is only 60%1RM. At such a low average intensity, this frequency approach is feasible. The volume at every workout is low and therefore the protein degradation at each workout is low. This is why you can perform such workouts more frequently. If however you were performing a standard hypertrophy loading based on performing at a higher %RM, the results would be detrimental.

Exactly on target Loopy.

There has also been done experiments with birds where they fixated the bird and hung weight from the wings.
Both strengths and muscle increased, without any rest…
I know, last time I checked I was human too. But intriguing none the less.
Isn’t this what CW’s quattro dynamo program is based on, what extra workouts and GPP workouts are base on?
An experiment could be to wear a weight vest continually for a longer period of days/weeks and see what would happen.
Impressive growth is my guess.
I bet one of you crazy t-maggers will volunteer :smiley:

What makes these “gurus” think that the CNS cannot be trained to accommodate more work? The human body is very adaptable over time!

I think it’s a matter of catch22.

As your training career progresses your neural efficincy increases (if you lift heavy for a prolonged period of time you will be able to recruit a higher % of your motor units).
Heavy training as well as explosive (DE days in the WSB setting)will improve your efficincy.
This leads up to a situation where your CNS might be conditioned to recover faster -but your ability to stress your cns has incresed too.
Not all tissues are able to adapt to a given stress as others. For instance skeltal muscle can adapt to recover way faster but due to the poor nutrient supply to cartilage and tendons/ligaments the recovery rate of these tissues will never improve as vastly as that of skeletal muscle. These tissue’s recovery is severely hampered by the lack of capillarization of these tissues. Muscles on the other hand are heavily capillarized.

This particular example may not be the best since the cns and nervous supply is often coupled with asessoriric blood supply…

Maybe some of the Bright heads out there can explain some of the mechanism behind the slow adaption of the recovery ability of the nervous system?

ps: plase don’t pound me on account of my alternative spelling/grammar. English is not my first language :slight_smile:

Thanks everyone for your thoughts. I am not, of course, thinking that I would like to place my muscles under constant tension (what with that being impossible and everything) or train them everyday but I find this an interesting topic which might explain why some report better gains with a greater training frequency.