Opinion About CNS fatigue

Came across an interesting read:

Most people think the only part of the body to adapt to lifting are the muscles, tendons, ligaments, etc. In fact, the brain also adapts to whatever stress you put on the body. It physically changes its structure and ability to deal with chemicals which directly relate to your physical activity. If you are a runner, youll get better at making and using chemicals which deal with running. Youll also develop and affinity for extremely short shorts, politics, FOX news, granola, etc.

One thing that pissed me off about IA is his insistence that the CNS fatigues? in some way. Bulls**t. People are still taught that the nervous system runs off of electrical impulses like a power cable. It doesnt. The nerve impulses (synapses) run off of chemicals (neurotransmitters). If these chemicals are not present, there is no signal between brain and muscle. The reason you can measure electrical impulses in the nervous system is because the electrical impulse is a BYPRODUCT of this chemical reaction. Its called an electrochemical reaction.

A large part of how strong we are is the ability to create and deal with a higher concentration of these neurotransmitters. The nerves develop more receptor sites to connect with them, and the glands learn to make more of the neurotransmitters themselves. Only then do you get a stronger impulse.

When you start placing demands on the brain to lift maximum weights every day, it says "oh crap I need to learn how to make and use these chemicals or hes going to kill us". So it goes through an adaptive period where it shuts down some functions and tries to upgrade?. These are the “dark times”?.

The main chemical in muscle contraction is SEROTONIN. It actually regulates how HARD the muscle contracts, which is why only the heaviest weights seem to effect our mood, the reason why people shy away from maximal lifting and cower from the imaginary symptoms of overtraining.

Serotonin just happens to be the main feel good hormone in the body. It directly effects your mood and mental outlook, your â??happinessâ? and willingness to train. Your sleep, appetite, and also effects the cardiovascular system (your heart rate increases when you are supposedly overtrained - this is why). The serotonin cycle in the brain gets screwed up when drug addicts go into withdrawl (most recreational drugs artificially influence the serotonin pathways, which is why they are so much fun). There are other neurotransmitters which get effected by this (acetylcholine for example), but serotonin is the big one.

So, when the body receives a demand to lift heavy things on a daily basis, the brain shuts down the serotonin receptors to upgrade them. The brain structure changes take a few days to a few weeks. Changes in individual nerves happen quickly, a few days at most. This is why the dark times occur. Its the adaptive period thats needed for the brain and body to get to the next higher level. Natures little joke is obviously making us feel like crap when we are actually improving.

The body is trying to get us to stop the stress so it isnt forced to remodel the whole place, but thats exactly what you want. Thats why its so important to keep pounding away through it all. You want the greatest adaptation to take place.

Guys who are afraid of this response are guys who are lifting because they like the way it makes them feel. If you do lighter workouts, this serotonin is raised, but there is no signal to adapt. You feel â??highâ?. Basically lifting weights becomes like a drug. People feel better doing light useless workouts, just like they feel better taking a hit of crack. I think this is why no one wants to try lifting the Bulgarian way. They are addicts.

You asked me about cortisol. There are no good and bad hormones. There are only hormones specific to your physical activity. Do you know why cortisol is released in weight lifting? Cortisol controls the blood pressure and concentration of blood sugar.

With short bursts of intense lifting (singles and doubles), blood sugar is not the primary fuel. Blood sugar only becomes an issue when you are doing higher reps. Cortisol is released mainly as a way to cope with these high reps, a way to shuttle more fuel (blood sugar) into the muscle tissue by using higher blood pressure. This is one reason bodybuilders have their posing trunks in a bunch over it. Cortisol is dealt with just like serotonin. The body tries to adapt to using it, and all the bodybuilders run and scream. If they stuck with it theyd go through a response much like the â??Dark times, and theyd be able to handle more high rep sets afterwards.

In this case, cortisol is specific to the activity bodybuilders, not power or olympic lifters. Keep your reps low and you never have to worry about it. (It has nothing to do with total volume, only reps in the set.)

Thats funny what you mentioned about the Bulgarians having huge adrenals. It makes sense. They adapt by getting larger and stronger just like anything else. Thats also a great argument against limiting â??geneticsâ?. Someone else would look at normal sized adrenals and say they would obviously be overloaded by stress. The Bulgarians entire organism changed in response to their lifting. Form follows function. Awesome stuff.

The adrenals dont only release cortisol, they release adrenaline as well. Adrenaline acts as one of the triggers to this adaptive period. You should go read the lecture by Ivan Abajiev here :

He explains this whole adaptive period and how it effects more than just the musculature. Go read the paragraphs which start with:

“So this is our aim when we are training athletes, that we would build up all those organs and muscles needed for a certain performance, not only the muscles, but the whole cardiovascular and other systems that support the working of the muscles in order for a better performance. The adaptive process however, does not only include all the lungs and the heart and the other organs that I mentioned.”

What do you guys think? can cns just be more a mental thing and a tradition than anything? Obviously you can’t train intense everyday, but maybe we might be overthinking about managing cns stress? If our body and mind feels good then I don’t see what’s stopping you from working with intensity.

Guys in the military go through rigorous training daily and manage to pull it off. Gymnasts train daily and have amazing strength and power and I don’t see them getting inhibited by their cns output.

So is recovery more art and personal judgement and mentality of that person than science?

Just some thoughts… I’m not trying to argue or anything but just open some perspectives and really think about what I am doing and why I am doing it in my training regime.

Reference, please!

There has been numerous posts in the bodybuilding forum but here’s one. It’s said by a guy named neuro doc who has a Ph. D in neuroscience



References about serotonin’s role:


Adrenal fatigue is just one manifestation of systemic fatigue. The whole picture, e.g. autonomic nervous system, hormonal system, of why an athlete is unable to perform maximally despite his muscles/tendons/ligaments being ready, is a lot more complex. That’s why Henk Kraaijenhof was critical of Charlie’s simplified muscle fatigue vs. CNS fatigue concept, although I think it works very well in the majority of cases.

Makes sense but how do sports athletes like soccer players train on a regular basis at a similar intensity or when they have tryouts they go all out for several days. Is it because this intensity is less maximal intensity than lifting or sprinting so you can recover quicker?

When there are tryouts, there is no choice. Practicing every day at a certain intensity doesn’t mean you train at your best possible ability. What you say vs. those other athletes/sports is also true, but football/soccer is more of an aerobic sport anyway, so more ‘forgiving’ in that sense.

That is true as well. I suppose doing individual technical drills with the ball on a regular basis is not much of concern to cns then (dribbling, change of direction stuff).

But it’s worth saying also that the ‘concept’ is simply that - a concept or theory - and as such is very useful for communicating and understanding the principles (Charlie espoused).
It’s an excellent model for training and managing training.

They usually don’t train at a similar intensity on all days.
Also, the intensity of training is so low that the greater risk is volume and structural overload generally (look at the injury tendencies)
And also in most cases they never lift so that aspect is untapped.

Yes that applies to pros. Other guys in lower leagues and lower levels sometimes don’t have that luxury and play consecutive games (in England lower leagues) etc. but I understand what you mean. It’s true but I’ve read about Kaka and Zico training with the ball alone even after practices and their training sessions at pro level when they went home. But I guess the intensity is low while training with the ball?

If the intensity is low enough it is a form of recovery, not training

What if you are a growing player and need to prioritize technical training, but still develop physically as well?

I remember reading some comments from Henk in I believe the 2002 Forum Review. Unfortunately, not all of us can tinker around with $35,000 worth of OmegaWave gear on a daily basis like Henk can, so a simplified concept of muscular vs. CNS fatigue is quite useful for the coach that has little access to advanced tools like OmegaWave.

On the bright side, there are some very inexpensive HRV apps like Ithlete that measure the basic markers of nervous system readiness. One of the athletes I work with is doing a classic CF short to long program and so far, it is quite stunning how well the CF high-low theory coincides with the HRV data.

Speed work drives the system down, and tempo work accelerates recovery. Once we have a pretty good amount of data, I will post a link to his graph.

Back to the original poster- you’re always better off doing too little rather than too much. Time and time again I see people try to “go for more” ending up with much, much less.

CNS fatigue would not be the primary concern in that case then - structural and developmental loads would be of more concern, so that’s what I would observe and develop the athlete technically with care of physical development.
(Youth training and youth development is not my primary area of expertise, so others could contribute better on the actual volumes)

Simply recording and tracking the duration of different training types (over a period of time/weekly) and performance, is a good guide for athletes.

Thanks so you think I can carry out doing drills like dribbling up to a cone with speed 10-15 m away and then doing a soccer move and accelerating away on a regular basis and not worry about cns fatigue from that?

Nikolouski, no23 and t slow,
thank you for making some needed and excellent comments about the central nervous system.
Bodybuilding is interesting but it has nothing to do with agility, speed, mobility … does it? Do body builders need to be fast? mobile? Aren’t they finally starting to recognize muscle density as an important aesthetic? Before bodybuilding favored big muscles over strong ones did they not? That’s ok but track athletes, soccer players, rugby guys etc… each sport has different training criteria and you want to learn from the sports that model your sport most. Right?
Dreambig, you are learning and trying to figure stuff out. I get that. Cf.com has some very loyal people who really care about teaching and helping others learn to train a particular way. Take a look at what some of these members are saying , look at their previous posts and take advantage of over 1 million posts on this site. A few of our members have made valuable comments to your specific soccer questions.
I will follow up with you as well as I have mentioned via email.
I can not supply you with loads of studies and cases regarding cns fatigue.
I am able to tell you I have been contacted by a cf.com member who is doing doctoral work in this area and he acknowledged historically there have not great research regarding cns fatigue ideas. He commented on the fact that he felt Charlie had made a great contribution to this area of study.
I think the balance of hard work, intense training and skill work with in the team sport make navigating some of this theory and experience tough.
How does a person see CNS fatigue? Can you see it? Can you feel it?
My guess is you are a very hard worker, very conscientious and extremely motivated without a great deal of formal coaching or solid information regarding training methodology? My other guess is you are likely to favor or respond best to shorter , faster work but NA soccer tends to build the endurance end of soccer possibly to the detriment of energy demands of speed and power ? ( in absolute terms)
I am frustrated listening to soccer dads and or coaches who tell me that soccer players need to do 400 meter repeats and distance running to improve their game.

I wasn’t talking about bodybuilding at all Angela. I know I got that in a bodybuilding forum but they were talking about cns fatigue from intense training. Anyways I’ve got my head around it and will try to make my framework around Charlie’s system except I will be playing both Sat and Sun pickup games (but soccer is not exactly high intensity cns like sprinting or lheavy lifting anyways). I think technicality is number one in soccer and then comes speed, power, strength, and endurance but that also depends on the positions. It has a high demand on aerobic system but having speed and explosiveness with skill can just make you much more lethal on the pitch and get you noticed or you must be a master technically and have a special ability somewhere like passing or shooting or dribbling or control. And yes your guess would be accurate about me :). I just want some more opinions on the questions I recently asked on the soccer thread and then I will carry it out and see how I respond.