In recent years I’ve begun to develop an interest in the concept of endurance, be it psychological or physical. This is a response to a combination of recent world events, the imminent grief that is part of ageing, and that I am aware that I have been lacking the capacity to endure since I was a child. A large part of this lack is due to the inability to self-regulate, this lack of self-regulation makes any provocation seem intolerable.
In a way, physical exercise requires the ability to psychologically self-regulate too. Without that, we are unable to tolerate the physical discomfort and mentally convince ourselves to do perform the activity just a little bit more. That is why many people would not take up something like running long-term. Running can be very uncomfortable especially for beginners – it just seems like torture. With adequate self-regulation we are able to hold the discomfort at some distance, not let it overwhelm the present, and instead focus on the longer-term goal. I have been interested in running not just for my physical fitness, I see it as an exercise for my mind too, because every time I don’t give in to my immediate need for comfort I know I am developing a capacity to endure. I believe that this capacity to endure physical discomfort influences my capacity to endure emotional stress too.
So I guess it is not surprising that I had to read a book titled, Endure. My chronic illness incentivised me to improve my health, leading me into a rabbit hole of reading books on health and exercise science.
I thought the book would be about the latest research on the aerobic capacity of the body since it was about endurance, but surprisingly it devoted quite a number of pages to neuroscience. The main message I personally got was that we had mistakenly believed our physical endurance limits were set by physiological constraints like muscles, vo2max, glycogen and lactate threshold, but in reality it is our brain that decides when we are done:
But starting in the late 1990s, a South African physician and scientist named Tim Noakes began to argue that this picture is insufficiently radical – that it’s actually the brain alone that sets and enforces the seemingly physical limits we encounter during prolonged exercise.
There was an interesting anecdote about an American ultra-runner who had to go through brain surgery for her epilepsy, and therefore it hampered her ability to judge the passing of time. Without consciously knowing that time has passed, she is able to run her 50th mile as though it is her first:
Unable to read maps or keep track of where she is on a course, she doesn’t focus on the challenge ahead of her. Hampered by poor short-term memory, she doesn’t dwell on the effort already expended, either. “I could be out running for two weeks, but if someone told me it was day one of a race,” she once joked, “I’d be like, ‘Great, let’s get started!’” Instead, she has no choice but to focus on the immediate task of forward motion, taking one more step, and then another. Semi-oblivious to the passage of time, she is also free of the cognitive challenge—the shackles, perhaps—of pacing herself. She is all hare and no tortoise—which, Aesopian morality aside, has its advantages.
When I read this anecdote it blew my mind. Without cognitive awareness of the past we are able to continue journeying in the present without being weighed down by the typical baggage we accumulate, so instead of anticipating the future with fatigue we can meet it freshly. It sounds like one of those zen teachings: that we should treat each moment as a fresh moment. Easier said than done though, there is always unconscious baggage, but in this athlete’s case her brain seems unaware even unconsciously.
What does this imply? That so much of what we do and what we believe we are capable of, is limited by what we carry in our minds? It seems that we are not only hampered by memories, but being mentally exhausted impacts our physical performance too:
After the mentally draining computer game, the subjects gave up 15.1 percent sooner in the cycling test, stopping on average at 10 minutes and 40 seconds compared to 12 minutes and 34 seconds. It wasn’t because of any detectable physiological fatigue: heart rate, blood pressure, oxygen consumption, lactate levels, and a host of other metabolic measurements were identical during the two trials. Motivation levels, as measured by psychological questionnaires immediately before the cycling tests, were the same—helped along by a £50 prize for top performance. The only difference was that, right from the very first pedal stroke, the mentally fatigued subjects reported higher levels of perceived exertion. When their brains were tired, pedaling a bike simply felt harder.
The researchers believe that by working on mentally draining tasks repetitively we can train our brains to be less exhausted, and this will translate to improvements in our physical performances:
If you could train the brain to become more accustomed to mental fatigue, then—just like the body—it would adapt and the task of staying on pace would feel easier. “I have an eye for things that at a superficial level seem crazy,” he said. “If I tell somebody, okay, I’m going to improve your endurance performance by making you sit in front of a computer and do things on a keyboard, you will think I’m nuts. But if something can fatigue you, and you repeat it over time systematically, you’ll adapt and get better at the task. That’s the basis of physical training. So my reasoning is simple: We should be able to get the same effect by using mental fatigue.”
Does this hold true the other way round? Will improvements in our physical capacity improve our brain performance as well? I believe it will, because exercise is known to grow the brain too:
“…conversely, exercise unleashes a cascade of neurochemicals and growth factors that can reverse this process, physically bolstering the brain’s infrastructure. In fact, the brain responds like muscles do, growing with use, withering with inactivity. The neurons in the brain connect to one another through “leaves” on treelike branches, and exercise causes those branches to grow and bloom with new buds, thus enhancing brain function at a fundamental level.”
This creates a positive feedback loop:
physical endurance <-> mental endurance
The part of the brain that governs the ability to mentally tolerate fatigue is probably the same part as the ability to consciously override our impulses (as defined by the book), also known as “response inhibition”. If we can gain the ability to consciously ignore the impulse to stop when fatigued, we can probably ignore other impulses too. Professional athletes seem to live up to the hypothesis that physical capacities can impact mental capacities:
The first interesting finding was that the professionals were significantly better at the Stroop task, amassing an average of 705 correct responses during the 30-minute test compared to 576 for the amateurs. In other words, to the list of measurable traits that distinguish the pros from the rest of us—the size of their heart, the number of capillaries feeding their muscles, their lactate threshold, and so on—we can now add response inhibition.
The book questioned which is the chicken and which is the egg. Are professional athletes able to develop superior physical endurance because they have superior mental endurance to begin with, or they have superior mental endurance because they have superior physical endurance? The author believes it is a bit of both, and I personally think this is just an outcome of the positive feedback loop I’ve just mentioned. The more we exercise, the more we can tolerate, and in turn we can exercise more. Endurance exercise requires us to inhibit our impulse to stop, and anyone who does endurance sports know it is as much of a mental game as it is a physical game. Each extra physical step we take requires us to exercise our mental choice to carry on, and making this mental choice over and over again will inevitably impact our neurological wiring.
For elite athletes, this translates to greater pain tolerance too:
In 2013, Freund published a telling study on the pain tolerance of ultra-endurance runners competing in the TransEurope Footrace, an epic pain-fest in which participants covered 2,789 miles over 64 days with no rest days. He asked eleven of the competitors to dunk their hands in ice water for three minutes; by the end, they rated the pain as about 6 out of 10 on average. In contrast, the nonathlete control group gave up after an average of just 96 seconds when their pain maxed out at 10;
…and they seem to respond to stressful environments differently as well:
Paulus and his colleagues have found that crucial differences show up in the activation of the insular cortex, a region of the brain that monitors sensory signals from within the body. In a series of studies starting in 2012, the researchers put hardened marines, elite adventure racers, and ordinary people through the fMRI tests. Some members of the control groups panicked and had to be removed from the scanner, but the elite performers handled the scenario with ease. In fact, while the control groups got worse at the cognitive task when their breathing was restricted, the elite groups actually got better—precisely the sort of performance under stress that enables you to dig a little deeper when the stakes are highest, whether in the heat of combat or at the end of a multi-day adventure race.
But what does this all mean for us mere mortals? For me, this just demonstrates the malleability of our minds and bodies. That they are capable of change, that we can probably push our limits further than we originally believed. We don’t have to be elite athletes to experience this change. In a positive feedback loop, any input will start the loop going.
I am a person who has issues with self-regulation, and I have terrible anxiety along with a great fear of grief. My feelings choke and paralyse me every single day. But I do experience some relief when I am exercising, the only time when I am in awe of what my body is capable of instead of feeling trapped within it.
Reading this book is a reminder of how powerful the mind is and how much it can influence physical performance. It also mentions that just talking to ourselves positively is enough to improve performances. There are more studies and powerful anecdotes, but I cherry picked those I related to the most.
Even though this seems like a book on physical endurance I think there are implications for our day to day lives. If our brain limits our performance during sports, it is also limiting our activity everywhere else. How can we stretch those limits? If I start playing mentally fatiguing games instead of shying away from them will I start to see an improvement in other areas of my life? Will I feel less mentally exhausted by stressful and tiring situations?
A sense of agency plays a great part too. The outcome differs when we train our selves voluntarily versus being forced to. Throughout my life I felt like I was being forced to do a lot of things, and I was always mentally exhausted by so many things that were out of my control. This is why these days I avoid mentally exhausting tasks because I am mentally exhausted from being mentally exhausted. Writing long posts like this is the only exception. But I do wonder if I can start to develop a stronger mental capacity now? Will growing a stronger tolerance to physical exercise grow a stronger tolerance to stress in general?
Just a couple of years ago I wouldn’t have believed my future self if she travelled back in time to tell me that one day I would enjoy running 8km effortlessly or that now I can pull myself up on a bar. Now, I cannot believe that I can grow to become psychologically stronger. It just seems so far, so unattainable. But who knows?
