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CNS Fatigue-My Definition


Everyone is using "CNS fatigue" as if it's a fact as solid as "sleep." I'm sure it exists, and involves the usual suspects like serotonin and norepinephrine. But I think it's far more ill-defined than people make it out to be.

When I was 20, the main causes of CNS fatigue for me were crazy girlfriends, Organic chemistry, and hangovers, not doing too many near-max squat and deadlift workouts. Now many years later, paying bills and keeping the wife happy causes me more CNS fatigue than lifting, although I clearly have to pace myself more carefully in the gym.
I'd just be curious to hear how other folks would define what gives them CNS fatigue, seriously or not.


I like the analogy about a tub with many faucets and one drain.

The more faucets (stressors) you have, the faster the tub will fill up (overstressed). There fore, you should turn down the faucets you can from time to time.

My faucets are:
1. My illness.
2. Not enough sleep.
3. Relationship woes.
4. Overtraining.


I forgot to mention. I feel it makes more sense to refer to CNS fatigue as being "tired", "spent" or "drained".

CNS fatigue indicates that it is caused mostly by training. The other terms seem to fit better.

I'm feeling a little drained now.


When I'm out of crank I get pretty stressed.

Serious answer though, I agree, out of weight room life generally dictactes my fatigue more than what I do in there. Maybe your Soviet Olympic lifter isolated at a black sea resort, fed meat and virgins everyday won't have that problem, but I do.



so before arguing with the wife next time, down your PRE-SSN shake. immediately after (don't wait to long there's a ~30 minute window), down your POST-SSN shake.

arguing with a wife is probably beyond a 1RM.

peace :slightly_smiling:


For me, deadlifts are BY FAR the greatest source of CNS fatigue. I only do one work set of deadlifts set per week on Thurs, but they always screw up my Sat workout. Squats and heavy Pendlay rows sometimes mess me up as well.

Usually, I eat a ton, but my weight is pretty stable at 245ish. Once, I tried cutting back my calories dramatically while staying on my routine, and it screwed me up big time. I got really fatigued, my lifts started weakening rapidly, and I had to take almost two weeks off to recover.


Having a vagina is the most taxing thing I have to deal with.

Really though, I agree that cns fatigue is a combination of physical and emotional stress that can come in many forms. I think people ignore it all to often and that's why it becomes an issue or more of a scapegoat depending on the person. I think that in order for your cns to withstand the stress of a hard training session you really have to leave your shit at the door and that the more successful lifters use the gym as a place to take out their frustrations and stress.

Under the bar is my happy place. So, I find that when I lift I actually feel less cns fatigue in general. Contrast showers help too. So does lots of sex.


Oh, Ericka. You know, you can't talk to a man just put on HRT like this... It's causing me CNS fatigue! lol Doc


I think a lot of people will like this definition, A Dynamic Model of Fatigue: www.powerrunning.com/Exercise%20Physiology/W


To me, CNS fatigue is not feeling good because my CNS worked hard all day, whether setting a DL PR or fighting an infection.


Well one time I tried doing rack pulls from a bit above my knee. I worked my way up to 560, the most weight I had ever held in my hands, or on my back was 475 for 1 rep 435 for 1 rep and 405 for 1 rep. So needless to say my body wasn't exactly prepped for so much weight.

The rest of the night, and the next day my entire body had a strange almost tingling sensation, and I felt sort of like I did the first time I took 2 HOT-ROX Extreme and an assload of caffine (super stimulated?)

I figured that if this was anything, it had to be CNS fatigue, but from other people responses I may be wrong.


Interesting you mention this. Yesterday, I had a two hour, high intensity workout, in the middle of which I did a 440 comeback PR deadlift and got 460 off the floor before I gave out. After the workout I went home and became a vegetable for the next couple hours, regrouped, but then could not fall asleep until 2 or 3 a.m. I'm sure the shock of the workout was the cause, how much overall body shock and how much "CNS fatigue" I don't know, but usually, when I'm just really physically tired, I sleep well.                                          Doc


For me it's when I'm physically fine, but I have a rapid drop-off of strength and training leaves my head feeling like I was concussed.
The weight will feel fine, technique is good, but it will move slowly or not at all when it is 50lbs lighter than a week or two prior. The pain and dizziness only happens during or after lifting. It's different to feeling like crap,sore, bad sleep, or a hangover. I've trained and hit PR's in various combinations of those. It is only really this weird pain coupled with feeling fine that appears to occur with the symptoms of CNS fatigue for me. It doesn't happen often, and always is better if not gone after a light week.

And for the record, the more frequently I hit that wall and recover, the more strength and muscle I gain. So it can't be all bad!


This is a great description, which I can relate to having experienced, all of it. And the last sentence...this is the part that puzzles me. It used to be a good thing to push yourself to hit that wall periodically. Now, at 50, I'm not so sure, but I still love pushing myself until I feel like I'm gonna collapse. :slightly_smiling: Doc


Sorry Doc, I should've qualified that last sentence! I just didn't want to make it too long!
I think the key is to hit the wall and recover. Depending on other factors, such as age, activity, diet and most importantly how much stress is in your life at the time, how long it'll take to recover will vary. So, as I think of it, you've got 3 things that could happen:

  1. You push your limits so far your CNS does not recover. This would result in an actual physical disease or syndrome such as chronic fatigue.

  2. You hit the wall, but the time and adjustments needed to recover result in either a loss in size/strength or less gains than if you did not reach that stage and continued training.

  3. You hit the wall, and you recover greater size/strength by recuperating than you would have gained from training normally in the recovery phase.

I think that 1. can only occur with world class athletes. It is very very rare to see someone who is so gifted physically and mentally that they can continue work at the very limits of their bodies abilities without getting injured for the time required for this to happen.

Whether 2. or 3. happens I think depends on the factors in your life, like stress and nutrition, in conjunction with how far you've gone past your CNS "threshold". Too little elicits too little gains, too much involves too long a recovery. It's all about the point of diminishing returns, and I think that recognising that point for an individual and how to use it to their benefit is what makes great athletes in any sport.

It makes great coaches too, but it is much rarer for a coach than an athlete, because an athlete has their own body letting them know. It's easy for an experienced athlete to "instinctively" know when it's time to back off if they've pushed their limits too far or too often.

Anyhow, hope that explains what I meant previously. I experience my symptoms, have a lighter training week, and come back bigger better. Obviously I'm going to keep doing what I'm doing until it ceases to work! If I had to take longer to recover, then it would start becoming a matter of diminishing returns and tweaking things until it works.

P.S Keep up the good work Doc, I saw your 4 month progress vid on your log. It'd be great to see where you are after a year!


I've recently began training to compete in olympic lifting at the 77kg class.

training for 2 hours straight with movements that im unfamiliar with its extremely taxing on my brain, then the workouts always finish with multiple sets of front squats that just destroy me.

I'm literally a vegetable for the next 3 or 4 hours, all i can do is lay in a hot tub filled with epsom salts and stare off into space.

THAT's CNS fatigue i think


This post makes me realize that I think it took me five months of devoted comeback just to get in good enough shape to actually train OL hard enough to produce this kind of state. That makes me feel better, I think!?     Doc


I love the feeling of being completely destroyed after long sessions with the oly lifts, pulls, and squats. I dunno I think it must be related to some kind of compulsiveness I have or something because I used to drink heavily and it elicited the same effect, I always felt "normal" with a brutal hangover. Whattya think, Doc? :wink:


I've seen many of your other posts, and since you asked, I think you have a Type A personality with a lot of fire in you. The fire has to be chanelled into something, or drowned out. Either way you come out wiped and content.

For what it's worth, I've got this sneaky hidden Type A, some have called an A-, where I seem calm most of the time, but I'm busy repressing shit and I channel fury into lifting. Oh, shit, don't get a shrink started....lol Doc


Hm, yeah Doc that does sound a bit like me alright. I've never a dichotomy of personality types into A and B before - so I don't truly know how accurate that classification could be. I have been tested as a very strong INTJ time and time again on Myers-Briggs tests, though. They seem a bit more accurate imo. I definitely do channel anger into lifting though and into just about everything, it's just the way I am. Good lifting!