My first thought was, "oh, reminds me of the SEAL's 40% rule... so if they're trained to ignore that limit, why don't they get hurt?" Then, in first google result [1], I read this:
“I first met “SEAL” at a 100-mile run in San Diego and I was running this race as part of a six-person relay team with friends and he was running the entire race by himself,” Itzler said.
“Who is this guy? I’ve never seen anything like it. And during the race, I kept an eye on him and around mile 70 — he weighed probably 260 pounds, which is quite large for an ultra runner — he had broken all the small bones in both of his feet and had kidney damage and he finished the race.”
So... yeah, this makes
Me think maybe I'll try harder at listening to my body (fwiw, I've screwed up arms/hands twice in past decade by pushing through fatigue).
Where does this come from in the larger culture? I can see why people who are soldiers or ... athletes at the varsity or pro level might be interested in it but why would anyone want to basically injure themselves as a ... hobby?
I've worked with runners who had serious injury, soccer players who came in with bruises that you'd associate with a severe beating... I'm thinking "geez, it's gonna suck when you're 62." Because when you lose some amount of basic mobility, you lose a lot of the ability to stay healthy when you're older.
Is this because of Mountain Dew commercials and 1980s GI Joe body image stuff?
> soccer players who came in with bruises that you'd associate with a severe beating
I was a lacrosse goalie in high school and didn't have the sense to wear shin pads. If you run your fingers along my shin, you'll feel divots where the bone never regenerated. I too used to walk around with bruises on my legs that you'd associate with a severe beating.
> Is this because of Mountain Dew commercials and 1980s GI Joe body image stuff?
It's considerably more primal than that. Sports are the modern equivalent to tribal rites of passage. We're not allowed to kill our rivals anymore, so we settle for beating them in a physical sport in order to establish our physical dominance. It's empowering in a way that few things are, especially as a teenager and extra especially if you were bullied throughout elementary school.
I was 120 lbs soaking wet when I was 17. The school gently guided me away from sports. Good thing, too. Best coach I ever had.
I graduated high school close to 1980. Sure, there were guys finishing the big game on a broken bone but it seems like there's a lot more emphasis on this now, and it seems more dangerous and higher risk. I have nephews and kids of friends who are electing out of organized sports.
FWIW, I feel lucky - we had basically one bully and he didn't last. Expelled.
I remember in "Brian's Song" where Alex Karrass' character sold cars in the pro football off season.
I dunno; I saw "Bigger, Stronger, Faster" and it gave me pause.
When I was 16, I was 130. That's after I spent three years in the weight room every day putting on muscle. I played every sport my school offered at least once, but I played football for 8 years. I never regretted it and I encourage everyone, especially the indoor geeky types, to try out for sports. Any sport. Even historical sword fighting. ;) It's an important experience that fewer kids are getting exposed to in this day and age thanks to helicopter parenting. Not to mention the life long social and health benefits
there are sports which will cripple your health in long run, almost guaranteed. many contact sports, it football comes to mind. some of my high school classmates are semi-cripples because of it (they can walk around, and that's about it). depression can be seen in their eyes - once you know what having a healthy and strong body means, and then losing it forever.
I've done my share of team/contact sports in my youth. nothing horrible happened apart from few broken fingers, but stuff I do now makes those sports look super boring/borderline idiotic when looking back (ie coach yelling at you like a little girl, running you around 'to break you to unlock your potential'). What I mean - trekking, skiing, climbing, via ferratas, cycling on unpaved roads, a bit of easy ski alpinism and mountaineering.
but I agree that any activity/sport is endlessly better than none, that's for sure
> depression can be seen in their eyes - once you know what having a healthy and strong body means, and then losing it forever.
I've talked to a friend of a friend who basically doesn't fear what normal people fear (e.g. talking to beautiful women, surfing, rock climbing, talking to strangers - he is really successful at sales). I asked him what his biggest fear was. He said it was to his lose health/lose control of his body (e.g. bad accident/paralysis).
We all have fears, and I think, in the end, we all fear mortality. And those who don't have the fears we most have (e.g. talking to beautiful women), fear their mortality/fragility of even the most fit body the most.
I never get whats the difference talking to beautiful women compared to anyone else? Im reserved and dont talk people much but there is no difference at all who those people are! Overall talking women is even bit easier as they are less dangerous on average.
For me, it's probably a holdover from my teenage years as a socially awkward and horny boy. I'm in my 30s now, but there's weird mental habits and impulses that are still sticking around.
I'm happily married, I don't cheat, I don't want to cheat, I'm really not interested in the "hot woman," but if I end up talking to her under any circumstances, there's a loud chorus of voices in my head screaming "dontfuckitupdontfuckitupdontfuckitup." I push through and get over my initial nerves, because I'm a grown up, but it's awful and annoying and I wish it would go away.
Wow, interesting stuff, i cant imagine any situation like that, even if i was operating my kid in life or death surgery i would not have dontfuckitup in my head, am i psychopath?
Not everyone. You don't have to be afraid of death. And before someone suggests it, this is not the same thing as wanting to die or even not caring if you die.
> there are sports which will cripple your health in long run, almost guaranteed. many contact sports, it football comes to mind.
Did you play football? The danger of permanent crippling injury has been blown way out of proportion by helicopter parents and the news. Of all the kids I played with and all the kids I coached (volunteer), only one of them ever wound up partially crippled. That kid in particular would routinely do daredevil stunts in his spare time. By the time he injured his knee, he was missing teeth, had blown his eyebrows off three times, and messed up that knee at least twice before stepping foot on the field.
Football is a safe sport, considerably safer than not playing. I hear on the news about concussions and crippling injuries, but I never see it in real life. Those things are pretty rare, especially when compared to vehicle accidents. I've seen far more lifetime permanent injuries come out of the soccer camp, to be honest.
Well, football ain't bull ridin' for sure. There's just something gladiator-exploitative about the whole mess.
Another anecdote: guy I know has a kid that's like a high school... sophomore and in order for this kid to continue to add value as a basketball player, he apparently can't afford to play HS varsity ball. It's a distraction. His other (older) son is approaching 7 feet tall and is totally over organized sports altogether, and is pointed at engineering.
What statistics? Nobody's provided any at this point in the conversation. If you have some, feel free to share. Otherwise, I'm going to downvote your comment as unproductive.
The statistics underpinning the fears of parents as to crippling injuries from head injuries in football are well documented, easily Google-able, and far more relevant than your anecdotal experience.
> it seems like there's a lot more emphasis on this now, and it seems more dangerous and higher risk.
College costs more than ever, so "pushing through" means you might make the playoffs, might get noticed and get a full ride. Hell, they're told, they might be able to go pro!
Very few people tell those kids the truth: It's a fool's errand. Only 1-2% of the kids who play basketball, football or baseball in high school actually go on to play in a division I school in college. Football players have the greatest chance of actually going pro, with a 1 in 600 chance of actually getting paid to pay pro ball... for an average of 3.5 years. If baseball is your game, it's 1 in 1850.
As the level of players gets better and better the game gets more dangerous. Rugby is a good example of this, over the past couple of years there have been multiple deaths because IMO the players are too big and too skilled. I watched a pro game from the 70s on YouTube between the two best rugby teams (NZ and Australia) and the level of play was shockingly bad, to the point that even an amateur club team now would have a good chance of beating them.
From a personal perspective I can say it's just routine. I get used to training every day and I like training with intensity (more sprint than endurance) but alas after years of repetitive strain injuries I have toned down the training load. It was unhelpful in the long run anyway as I would train for 9 months then need to sit out for 3-6 months and be back at square one (usually shin splints). My body (knees especially) aren't thanking me for it but it's nothing that can't be fixed without a good chiropractor and lots of cross training (mainly cycling and weights but yoga/pilates, running and swimming too).
I learnt a lot from how a buddy who is/was a world class 24 hour mountain bike racer trains. His view is long term, building up fitness slowly over years. I do admit I find it much harder to maintain routine now that I have pulled back the training load.
As someone who has injured himself for a "hobby" a number of times:
My "hobby" is a means for me to challenge myself, to push myself to my limits, to see what I am capable of and take my measure as a human being. It is a means for me to learn how to overcome fear, pain and doubt. It provides an objective haven when the subjective world is upside down.
The 40% rule is useful if you're in combat and your life is on the line. But then again, in such a situation the adrenaline would make you ignore any pain or fatigue anyway.
In normal life this 40% rule seems just stupid.
Something seems fishy about that story. Not only are special forces people usually smaller, but getting hurt is a big no no. It will stop your training and severely jeopardize any mission you're on. Most special forces teaches the opposite of "if it's not hard we don't do it" i.e. to use your tactical advantage. That said, getting in to US special forces probably isn't that selective these days with having had to fill a lot of "seats" for various wars.
Anyone in any branch would be subject to charges for negligently incurring injury. I've heard a story about some guys in the Air Force who were written up for getting terrible sunburn while boating.
Digging in with Google, the writer is much less than a billionaire (though perhaps with more arrogance than one) and the seal was much less than 260 pounds. I have my suspicions about breaking every small bone in his feet and kidney failure too.
And even if that story is true - how much glory is running until one gets kidney failure?
The story wasn't told well in that post, but it is legit. I've heard him speak in person before. The way he tells it, he had three years of non-deployable time so it was the quickest way for him to accomplish his goal of getting into the Badwater ultramarathon to raise money for charity. Not ideal, but he knew that he would have time to fully recover from it.
'Protection' might be the goal of physical fatigue, but it doesn't work for intellectual effort - what are you being 'protected from breaking' by not being able to write another line of code? Carpal tunnel? In that case, it looks more like it's about conserving energy or rotating to another task after having spent so much time on one task: "A Meta-Analysis of Blood Glucose Effects on Human Decision Making" http://www.gwern.net/docs/2016-orquin.pdf , Orquin & Kurzban 2016
"An opportunity cost model of subjective effort and task performance" https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3856320/ , Kurzban et al 2013
What about mental fatigue? The more you workout your brain the more it needs to rest. How would you like your brain to tell you that it needs to rest other than feeling fatigue?
I find myself consistently productive over long spans without a burnout effect when I am sleeping at consistent hours, and working for consistent hours a day. When I overwork my productivity becomes inconsistent so I stopped doing that. I learnt it the hard way that late night coding is a short-term investment with negative return in the long run.
My personal theory is that our brains like consistency and adapt/tune to it over time. Just like when you jog every day, if you run for too long one day and too short the other day it cannot adapt/tune itself to a semi-random pattern.
There are two reasons for mental fatigue as best as is known/we can infer. The first is stress from the task (by which I mean the immediate thing that is correlated with cortisol levels). The second is that maintaining attention on a task, where there is not much reward or feedback on the task's progress makes maintaining attention harder and harder to do as time progresses. Imagine a very heavy door that wants to swing back shut the longer you hold it open. Resisting this too is linked with stress inducing mechanisms.
A good theory should explain why watching a television serial, a very complex task involving long term memory retrieval, short term memory of details, inferring various motivations, theory of mind (on a meta level too via genre savviness), agent modeling and prediction, language, visual, audio is less taxing than solving 1000 simple arithmetic problems. The resource management and attention based theories have better explanations for why that may be.
I find I can be highly productive with a highly inconsistent sleep schedule as long as I get significant amounts of sleep every few days. I don't think a consistent schedule is a requirement.
I heard different story: there is no such thing as "mental fatigue". The reason why we get tired when doing office work is:
- our muscles need to support our body while sitting.
- most mental work includes some dose of stress, which is a real reason of fatigue.
Buy yourself best chair you can find plus do stress-free, enjoyable work and you can go 16 hours straight, without fatigue. At least that's how I felt about all-weekend-long Quake matches back then when I was living in dormitory.
I think it depends on the task. Playing Quake doesn't require significant amounts of creativity or learning, in the same way that programming or learning a new language would. We know that the brain needs sleep in order to process new memories, so that may be one factor in mental fatigue.
This is anecdotal but I have often noticed that I become more thoroughly fatigued and thus need more sleep when working on really hard programming problems vs less mentally taxing tasks. This implies that it's more than a physical phenomenon.
Perhaps from bad decisions? As I stay awake, the quality of my code drops pretty fast, social decisions get worse, I say the wrong thing to people, et cetera.
That's conflating two different senses of fatigue. "We feel tired to prevent us from making mistakes when we have been awake a long time."
That separation of the different senses of fatigue is the core of the article. Fatigue is both a feeling and a state, which we confuse because they are connected. But you can give someone drugs, like diphenhydramine or caffeine, which change the feeling of fatigue without changing the underlying state which that feeling normally reflects.
"The brain makes up 2% of a person's weight. Despite this, even at rest, the brain consumes 20% of the body's energy. The brain consumes energy at 10 times the rate of the rest of the body per gram of tissue. The average power consumption of a typical adult is 100 Watts and the brain consumes 20% of this making the power of the brain 20 W."
The resting metabolism is very high, because the brain is expensive to build and run. But it's not much more expensive to run on one task rather than another. This is one of the major flaws in the blood glucose theory of willpower as discussed by Kurzban: some additional sugar can't be 'gasoline' for the brain because the brain doesn't use up that much more energy working on something than not working on something. (As one might guess from the basal rate of 20%! Not much room left. Or from thermodynamics: when you walk or do physical exercise, you can feel your body heat up from how much energy you are burning. Your head doesn't heat up while doing arithmetic.)
This assumes that fatigue is merely a thermodynamics problem. Fatigue could also be caused by the depletion of chemicals which take time to regenerate. Such effects would not be captured when looking at energy usage alone.
You assume merely logical work in the pre-frontal cortex. As soon as emotions come to play the body get's involved because heart-rate, body-temperature etc. is influenced.
And I don't mean emotions like anger, but less visible ones like disgust, which seem to be triggered during procrastinating.
It might be protecting you from becoming so brain-fuzzed you can't respond appropriately to "legitimate" threats. Conserving spare capacity for when the predator shows up.
Having taken neuroscience courses for interest in the subject, the holes in our knowledge far exceed the knowledge - even if the introductory book is over a thousand pages (but that's how it is in most fields these days, and yet you only learn basics).
For example, only very recently we found that the brain literally cleans itself (by flushing) during sleep (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3880190/). You can bet your Tesla (if you have one) there are lots of mechanisms for physically cleaning up and regeneration that we have no idea yet that they even exist. It's also recent that we find that the various glial cell types in the brain actually help in computation and are not just "helpers" you can leave out when considering brain activity.
I know for myself that when I lie down even when I am not tired (and I rarely am during the day) my brain after a while starts doing some really weird stuff. It's literally like day-dreaming. I have no conscious control, I just let it flow - but I'm not asleep, not one bit. That lasts for 5 to 20 minutes. Afterwards I feel incredibly refreshed. Again, there is no sleep involved, not even half-sleep, so it's a very different mechanism.
All processes are physical in the brain in the end: Even electrical activity is performed by ions, not by electrons, after all. So even electricity is physical movement of atoms, unlike in human-made electrical equipment where it's just electrons for the most part (you see the effect when it's ions in batteries, if you open them when they are old, while a copper wire doesn't change even after years of current flow).
In addition, part of electrical activity performed with ions is the transmission to another cell (within the brain mostly other neurons, of course), which is purely chemical through various transmitters. When I first heard about that I thought "couldn't this be optimized in a human-made system to stick to using only electrical signals, it would be sooo much faster". However, I quickly abandoned that thought, those transmission being 100% chemical is a major part of the information processing. Human-made computers show you can do make something "purely electrical" - but then it works following completely different principles. The chemical vector adds a huge flexible component to the system, it enables the majority of what the brain is and can do. But it means that a huge chemical factory has to be maintained: A gigantic amount of molecules needs to be synthesized and broken up continuously, and vast amounts of it. And while you don't need to do much cleanup except for dust in a computer because it's all just electrons, the brain is less electrical than a chemical factory.
Even the electrical activity which uses just simple ions, so they are always there and don't have to be manufactured, uses a lot of energy, because the gradient has to be maintained by physically moving ions back out of the cells to establish the resting membrane potential. That energy comes from ATP, which first has to be produced. In a human-made system we simply provide the electrical field to the entire system from the outside, and the dirty chemical processes have been outsourced to power plants somewhere far away. In the brain you have all that waste-producing activity right in each cell!
Add to that that there is so much activity in the brain, much more than in most other tissue in the body, and you can see a lot of "house-keeping" has to be performed. And that is an area that we still know precious little about. So it seems plausible that occasionally heavily used parts of the brain may want a little rest - during which they don't really rest, they just do cleanup and maintenance.
What's a relatively recent write-up of this stuff for a non-specialist that doesn't skimp on the details? I'm not asking for Cognitive Neuroscience for Dummies but I'm not asking for "think of the brain like a CPU" either. If there isn't a decent write-up, could you write it? I'd buy a copy ;-)
Brings to mind the claim that we have X hours of focused mental effort we can spend each day. Go beyond that and we start dropping back to fight or flight instincts etc.
However, I don't think that is actually a real theory in neuroscience, it's more a made-up everyday rule. I doubt it is valid, except in the most general kind of way.
This meshes perfectly with the general view of endurance athletes that performance is largely mental. If fatigue was strictly limited by lactic acid buildup then your state of mind wouldn't make such a dramatic impact.
When I go running, it's some kind of aerobic sensation, but eventually my thoughts shift when it's time to stop.
If I lift heavy things for an hour, I can also be quite winded but there's usually some gas left in the tank I just know it's better to get some rest and allow muscle to repair.
Some kind of crossfit style workout, yet another sensation.
Sometimes I can take a nap as soon as I get home after the above, especially a vigorous run in the Arizona desert during summer.
Knowledge work has its own fatigue for me. If I go deep into flow state while working on something, eventually I reach a generalized mental haziness, where I want to relax and let my mind wander or be passively entertained.
Usually I have trouble sleeping after intense thinking, mind still firing but not effectively. I just want to "chill" and watch TV or do something simple and rewarding like clean the house to try and bring it fully out of gear.
> This meshes perfectly with the general view of endurance athletes that performance is largely mental.
Most elite endurance athletes do not hit the lactic threshold during their actual races. That is why they train so much - to build their endurance. Once you hit the lactic threshold, your body starts to break down.
Enduramce athletes go just bellow lactic threshold most of the time. The body is OK to go above threshold, but only for a limited time. The key is to correctly time usage of that above-threshold capability.
I race MTB. Both quick races and long, 100 miles or even 24h solo events. In a quick <3h race, I just go all-out and stay above threshold most of the time. But I try to time my above-threshold usage in long races. In one of the 24h races, the course had a single climb. I was riding everything but that climb bellow threshold. It would have been very hard to stay bellow threshold on it. While it was just a couple minutes effort above threshold.
Lactic acid buildup does not have the relationship to fatigue that you are implying. Common myth. For more and in from far more knowledgeable persons than me:
http://www.scienceofultra.com/podcasts/10
Anyone who has gone to the gym after a protracted absence and loss of fitness will have some intuitive understanding of this. Your brain hasn't quite gotten the memo that you're not in the shape you used to be, and it's really easy to over-exert yourself. You feel fine during the workout, then throw up afterward and take much longer to recover.
Very true. I learned this the hard way, in my case I ended up with a stress fracture. My mind was actually refusing to get the memo, even when I started feeling pain.
In light of this article, wonder what type of psychological training could be used to complement the typical physical training to improve athletic performance?
Maybe something that copies military basic training. It has been decades, but I can still hear my drill instructor yelling, "You aren't tired until I tell you you're tired!" He was right.
>90% of fatigue in basic (based on a scientific study I just made up in my head) is mentally induced because recruits have a belief of their limits that's short of reality. Part of the drill instructor's responsibility is to demonstrate these limits are just mental by pushing recruits beyond them. Of course, that still leaves the <10% of times when the limits are real and someone gets hurt, but that's just collateral damage, I guess.
I wonder if it's really 10%. The instructor most likely doesn't actually know the person's limits. They're setting a baseline and hoping everyone has good enough genetics to meet that baseline. The rest are injured/kicked out/may have actually been filtered out earlier. Remember that the military turns down many people, and that often includes a lot of people who have hidden medical issues or just bad genetics.
I hate cardio with a vengeance, and the most effective way I've found of getting past that was to make use of meditation techniques: Fix my mind on my breathing, and keep it there. Not allow myself to pay attention to anything else. First time I did that, I ran twice as long as what I'd one previously. It works great for activities you can do "automatically", whether the reason you want to stop normally is because they're physically demanding, or boring (like cleaning the house).
Another approach is to set a goal, but keep moving the goal posts.
"Tricking yourself" that way can be surprisingly easy - I first consciously tried that (though I'm sure we've all done it without thinking about it) after thinking about how easily we trick ourselves into continuing pleasurable activities that way, or procrastinating ("only 10 more minutes, then I'll start working"); it works quite well for me as a means to continuing exercise or work too.
What'd be incredibly intimidating as a goal at the outset suddenly seems a lot more achievable if you set a more modest goal to start with.
This also makes sense if you think the evolutionary biology of it: if after a small number of top runners separate from the pack (even if they happen to be the "top" runners of a race by pure luck, and even if their relative order is pure luck), it's better if the 2nd, 3rd runner etc. accept their places at a point and don't push more, because then the top runner will also push more and so on... positive feedback loop until some of them (maybe all!) die of fatigue.
Cowardice of the individual might be a huge survival advantage for the species as a whole!
Without it the species might end up loosing or injuring the fittest of the individuals in stupid competitions. The would be quite detrimental for the species.
(Also going even further from physical performance: If you extend this a bit from "athletic race" to "nuclear arms race" you'd see a similar thing ...but yeah, as an individual player you might "loose" by being coward (although I would not call "staying alive" loosing...).
And an interesting philosophical question would be about the cases where an individual gains courage by loosing "the feeling of being the same species as the others" - we know that psychopaths ca be quite fearless, and we also know from history that if you train your soldiers to think they are "a superior master race separate from the others" they tend to get quite better at winning battles.)
If the claim is that muscles don't fatigue, then I am skeptical.
In college, I took a weightlifting class with a bunch of athletes in it. One day, we did lunges (no weight) around and around, in a line like ants. Nearing the end, my brain thought I was totally fine. I cannot stress that enough. Bam, like a light switch, my legs went from 60% strength to 2% three quarters of the way through the last lap. Had the instructor not caught me, I would have fallen right over.
Why do you suppose your legs went from 60% to 2% so rapidly? Do you think your muscle really depleted in function that quickly, or did your brain cut off the electrical signals to the leg in order to protect it from permanent damage?
But you're correct in that there is more to it. Adrenaline masks fatigue. It allows you to temporarily exceed what your brain would normally allow you to do in order to save your life. You pay for it later, though.
I would recommend reading the article, it is fairly interesting and suggests based on the body of research that the brain (subconsciously) creates the emotion of fatigue prior to muscle "exhaustion" to prevent injury.
"These sensations of fatigue are unique to each individual and are illusionary since their generation is largely independent of the real biological state of the athlete at the time they develop."
No, I think you are anecdotally supporting the posted article: you worked your muscles to physical exhaustion but you did not feel "fatigue", ergo, the conventional theory that "fatigue" is caused by lactic acid or other muscle chemistry is disproved.
> If the claim is that muscles don't fatigue, then I am skeptical.
No, the article isn't claiming that at all. It is saying there is an extra system in the brain which generates the sensation of fatigue. This usually happens before the muscles reach their limit (and this has been demonstrated).
As others have noted, it may not have been your muscles. Why would your muscles suddenly go from 60% strength to 2%? I suspect either it was central fatigue (which can also manifest as muscle weakness), or perhaps your form was wrong on the last lap.
"conscious mental decisions made by winners and losers, in both training and competition, are the ultimate determinants of both fatigue and athletic performance."
A favoutite quote of mine: "You have to make a sustained 'conscious effort', to win."
I can buy the conclusion except that I believe you can only usually tweak performance in small degrees without actually over-exerting yourself, since the central nervous system _is_ in fact an expert on what you are capable of doing safely.
I think the point is that you can keep increasing performance in small degrees, so it's kind of like training your brain to allow small incremental performance boosts by saying "see, I didn't get injured or die, so give me another 1% speed". Of course, sometimes this does actually result in injury, so if you want to be safe it's probably best not pushing too far.
"Fatigue makes cowards of us all" is a famous quote supposedly from Vince Lombardi, though it has also attributed to other significant people (as famous quotes often are).
Regardless of the speaker, the overlap with the headline is remarkable.
This is an interesting method of building resiliency -- or anti-fragility -- into a complex system without adding complexity via a system of feedback for each component (or some other such cleverness).
(I.E.: Have an overarching "intense activity" timer or measuring device signal that the system is likely to suffer breakdown... just because it probably will.)
The key intelligence here comes from the fact that the human fatigue system evolved alongside the human organism, and thus has millions of years of results built in. As a result it's fairly accurate.
I suspect it has been around quite a while in evolutionary terms, and isn't just in humans. All animals need to be careful that they don't overheat, go without water, break a bone, etc. (However if another animal is chasing you, it makes sense to turn off the inhibiting signal). The brain regions involved are common to many animals AFAIK.
I'm doing rather exhausting martial arts, which includes doing all movements at exact the speed in which the trainer counts.
There were moments where I felt I couldn't proceed and was exhausted. When telling that to my trainer he, correctly, said: well your muscles aren't shaking under load, so you can't be out of energy yet. After a pause of 10 seconds I was able to go on.
In my experience most physical fatigue can be countered by proper, regular and deep breathing during movement. It seems to be an oxygen-distribution problem.
never forget that a different conclusion can also come from a different input. Maybe your understanding of fatigue is not the same as the author's. You could already see two definitions when comparing yours with your trainer's, right?
It seems to involve the same brain regions that Noakes identified as being involved in physical fatigue. However rather than protecting against damage, its function appears to be to protect against unnecessary expenditure of energy.
Maybe. In my case it's often protection against bullshit things I have to do but I'd rather don't. Sadly, the "system 1" in my brain doesn't understand that it's not just "have to do", it's "have to do, or else...".
“I first met “SEAL” at a 100-mile run in San Diego and I was running this race as part of a six-person relay team with friends and he was running the entire race by himself,” Itzler said.
“Who is this guy? I’ve never seen anything like it. And during the race, I kept an eye on him and around mile 70 — he weighed probably 260 pounds, which is quite large for an ultra runner — he had broken all the small bones in both of his feet and had kidney damage and he finished the race.”
So... yeah, this makes Me think maybe I'll try harder at listening to my body (fwiw, I've screwed up arms/hands twice in past decade by pushing through fatigue).
[1] http://thehustle.co/40-percent-rule-navy-seal-secret-mental-...