T Nation

Muscle Capacity


Alright I know that some of you are very knowledgeable so I hope you can help me.I've read lately that your brain only allows you to use 20% of your total muscle capacity.Supposedly if you use more than this your muscles will tear and rip from the strain.So my question to all of you is:

1.True or False
2.Is there any truth in it(ie. you can only use 80%)

I also have a favor to ask,don't call me stupid.It kinda sounds like BS but it intrigued me and I havent been able to find a definite answer from anywhere.


Actually I'm pretty sure this is true to a certain extent. I'm sure it's different for everyone, but many rote beginners just have very inefficient nervous sytems.

I think it's less of a protective mechanism and more of a thing where your nervous system needs to learn how to send a stronger signal and activate more motor units.


It's more complicated than that.

Your tendons contain golgi tendon organs which inhibit maximal contraction for either safety or coordination reasons, probably the latter. These supposedly can be detrained.

I have to distrust the percentage there, however, it sounds like the people only use 10% of their brains myth.


so your body does limiters on?

can you point to a place where I can read up on this?


Isnt' this why some people strech with the large foam rollers?


I think it's quite obvious. Remember when you first started lifting weights you had zero control. After that (if you didn't eat enough) you could carry on gaining strength but no size? or the stories of women lifting up cars to save little children? It's all an example of using your motor units hidden deep down, used only in emergencies.

You can get more and more efficient at using them, which accounts for why guys like Cressey can lift ridiculous amounts without all that much muscle mass (in the scheme of things)


Basically you are referring to the "Golgi Tendon Reflex."

This prevents you from lifting or stretching a muscle well beyond it's capability. Which of course prevents you from damaging your body.

Simply google "Golgi Tenndon Reflex" and you can read all about it.



Ask I understand it, that is true that your muscles and tendons have limits of their actual strength they are held to. I've also heard that under certain circumstances these limits can be ignored. This would explain stories where women lift cars to save their children or where drug users break handcuffs.


This is where the mind-muscle connection comes in. Neuro-musclear adaptation is what's responsible for a beginner trainees initial strength increase. Kinda like when you hear people say " Man I'm sore in muscles I never knew I had." If the toughest thing someones ever had to do is rake a yard or push a lawnmower then it's obvious the higher threshold motor neuron units have never been asked to work. The woman lifting cars in an emergency is different. Thats more of a release of ephinedrine and adreneline than motor unit recruitment.

I personally believe the human brain is incredibly untapped and people have no clue as to what the brains potential really is.


Just an observation but wouldnt your "capacity" be the point where they tear? I wouldnt be suprised if the body limits what a person to can do to an extent as a safety net but 20% seems a little bit unrealistic.


I think from a survival point of view it makes sense to have an "everyday" limit versus a "emergency" limit.

Everyday limitations would basically make it difficult to injure yourself by simple exertion. If you are hunting and gathering an injury could be very detrimental to eating and hence survival.

However, in an emergency, such as when fighting for your life against animal or foe, an injury is a much better option than losing the fight.

While this is all hypothetical, it does jibe well with anecdotal evidence such as a mother lifting an incredible amount of weight to save her young or listening to stimulating music instead of Linda Ronstadt.


Here's a good place to get an understanding of the basic set-up.

A bit more involved...

Golgi organ inhibitors INHIBIT motion. They tell your CNS how much tension is on the muscle and your CNS responds by inhibiting contraction or lenghtening of the muscle so damage to the body does not occur. These safety catches are set really low to be on the supersafe side so you don't hurt yourself. Under outside stimulation like severe electrical shock, your muscles can contract hard enough to fracture bones. See, your muscles are capable of generating a lot of force, but your CNS is designed to prevent you from exerting enough force to do damage to yourself. And again these controls are set very, very low. Through proper training, you can constantly set back those safety parameters.

(Here we go with the percentage of 1rm and rep range theory again...)

Training over 90% or so of your 1rm causes increases in neuromuscular efficiency, rate and coordination of firing and golgi organ DISinhibition. Strength is very much a skill in which your CNS rewires itself to make better use of the musculature to generate force. Training below 90% of your 1rm and above about 80% tends to cause strength increases mainly due to growth of the contractile tissue in the muscles, the myofibrils. So training with weight you can handle for 4-6 reps makes you stronger not so much because you're improving neuromuscular efficiency, but because you're stimulating the addion of the stuff that contracts, thus becoming more muscular, but in a way that lends itself to increased density as opposed to volume. For noticeable size increases, training with loads below 80% is required as this increases the sarcoplasmic content of the muscle, or the stuff that fuels the iia fibers (the bodybuilder look).


I don't remember where I read this but I think the average person can activate between 20 and 30 % of his muscles, but I think it can get higher than that for well trained people, maybe 50-55% for olympic lifters/powerlifters etc. Just my 2 cents.


thanks guys,specially snatchandcleanjerk.Alright here's another one,what do you think would happen if there were no limiters.And what would be needed to cause this.

See this is why I love this,our body is THE ultimate machine.


You'd break a bone or pull a muscle out of its attachment points every time you made any sort of exceedinlgy swift, forceful movement. Again, this is what happens sometimes during electrocution when the muscle is stimulated to contract and that stimulation overwhelms the body's built-in ability to inhibit too much contraction.

You can keep pushing back the level at which inhibition occurs by training with very heavy loads over 90% of your current 1rm in a movement. This rewires your neurological hardware to accept a certain amount of force generation as "normal." It's the same way constantly practicing your repetoire on an instrument makes your CNS accept the prescribed finger, hand and arm movements as "normal." If you practice enough, playing any song in your repetoire becomes second nature. Same sort of thing happens when you can dial a number without consciously thinking of the individual digits because your hands and fingers "know" the dialing sequence as it applies to a telephone keypad.

Your golgi organs protect you from hurting yourself during strenuous effort, but with intelligent training you can teach your muscles to contract more forcefully and beyond the inital disinhibition limits which translates into real-world strength. You're essentially retooling your CNS interpretation of the information it receives from the golgi organs. Whereas the "information" that you were attempting to generate enough Newtons to overcome the inertia of a 135-lb barbell atop your shoulders was once enough to cause the related musculature to shut down, enough training gets you to the point where that 135 lbs is inerpreted as "well within operating limits." The new limit may be 185 or so because you practiced in 1% increments to get there. With more practice it eventually becomes 225, then 275, etc, etc.


It is true to a degree as everyone outlined above. If you exert too much strength you WILL rip your muscles or tendons off etc.. and in nature, that is a showstopper ie if you rip a muscle in the wild, you might end up dead. Tendons and ligaments even worse. Or at least very dysfunctional.

Often people using steroids develop increases in muscle strength far faster than their tendons can grow / strengthen to match the muscle strength and this can cause injury.

Also this phenomenon was part of the theory behind the comic "Incredible Hulk" - because in times of severe emergency the body just lets go and you can draw on super phenomenal strength e.g a woman lifting a car off her child. The whole Hulk thing was a very interesting premise.

Furthermore people who go insane often recruit far more of their strength and they are just plain scary and very difficult to pin down.

I believe many of the old world strongmen through years of training developed very strong tendons and ligaments and therefore were strong despite not being overly huge. Similarly, people who have done hard labour for a long time.

There were some strongmen of old who had "double tendons" - a genetic anomoly as whacky as people who have extra fingers but far more useful. Imagine being born with tendons and ligaments thicker and stronger than normal. The advantages would be incredible.

I believe that static holds of extreme heavy weights are good for stimulating tendons and ligaments strength ... monkeys also come to mind, hanging statically off branches etc.. they have very strong connective tissue. And not mega-bulky muscle.


so do you think training in the 5-6 rep range increases your muscle capacity in that way of your CNS allowing you to use more muscle capacity? or are you just getting stronger because your making more muscle fibre?


Something like 3x3 with quite long periods I suppose would be more like it. Pavel goes and rants on at length about this strength without size buisness from recruiting more and more Motor units. You're not growing bigger but you are getting stronger...


let me tell you my experience.i have strenght that is average for someone who lifts weights.i boxed for last 4 years and my goal was to get stronger without getting heavier to remain under 81 kg class.in the last 3 years i incresed squat from 240lb. to 340,bench from 200lb. to 230lb.,deadlift from 240lb. to 410 and power clean from 120lb. to 210lb.,while i lost 5lb. of lean mass/muscle.i powerlifted many sets/ low reps,olympic lifted for sets under 3 reps.mostly important,i ate same amount of food.i didnt lost any fat.


This is what is known in technical terms as "retardous strengthacus."