How to push yourself beyond your physical limits

Swathes of research and real-world accounts have proved that the mind has an inbuilt safety net to stop the body exercising well before its physiological limit. But rather than take this lying down, studies are also showing that it might be possible to mentally override the heavy breathing, burning muscles and onset of fatigue. If so, then how can we hack our own grey matter, and is it wise – or indeed – safe, to do so?

Published: March 13, 2019 at 10:38 am

Claire Smith knew so little about triathlon that when she entered her first Ironman, she believed it was an obstacle race. The 34-year-old from Bournemouth couldn’t really swim and didn’t own a bike, but battled through Ironman UK in Sherborne in 2008, and immediately signed up to go double the distance. She was hooked, but it wasn’t enough.

“I decided that the world needed a harder style of double iron-distance race, and after a lot of hard work, sleepless nights and money I didn’t have, I started the Double Brutal,” she says. It involves a run to the summit of Mount Snowdon in North Wales, and now, in its ninth year, Claire has even added a triple option.

Yet as a triathlete, she ploughs on, finishing the Swiss Ultra continuous deca in just under 12 days and has entered a continuous double deca in Mexico in October. That’s a mere 48 miles of swimming, 2,240 miles of cycling and 524 miles of running, where you can stop, but the clock won’t. “I have an extreme personality and have always been drawn to the crazy stuff,” she admits. “When I was younger, I got into drugs and alcohol, but found the ultra-world a better place to be.”

While Smith takes an extreme approach to testing her limits, we’ve all experienced the compulsion to slow down or quit during a race. Whether it’s a Parkrun or Ironman, any aerobic event offers an opportunity to up the intensity and become accustomed to discomfort.

“In a complex world, this is one area in life where the measuring stick is simple,” says sports science journalist Alex Hutchinson, author of Endure: Mind, Body and the Curiously Elastic Limits of Human Performance. “You can engage fully in the task and realise when you are getting close to your limits. That’s attractive, as there’s always some mystery in how hard you’re going to be able to push on any given day.”

Perception of effort

But how fixed are those limits? That training is a prerequisite to improve is universally accepted and understood, but beyond optimising our physiology, to what degree does sheer bloody-minded willpower become an influencing factor? Is the key to Ali Brownlee’s winning psychology, for example, all down to being more motivated than the next man on the pontoon? No, according to Samuele Marcora, professor of exercise physiology at the universities of Kent and Bologna, Italy, and a world-leading researcher in the limits of human endurance.

“Matt Fitzgerald wrote a book entitled How Bad Do You Want It,” Marcora explains. “I love the title, but it’s a bit misleading. What distinguishes one top triathlete from another is not how bad they want to win a certain race because as soon as they’re both willing to exert maximal effort, motivation is no longer a limiting factor.

“What limits performance is their perception of effort and how quickly this increases over time. An even-paced marathon feels much harder after 40km than at the start. How quickly the perception of effort rises will determine whether you can keep a given speed.

“Heat exhaustion aside, we do not reach our physiological limits when racing. There are also psychological factors, and the beauty of our modern research models is that we have data to prove that you can still improve performance when nothing changes from the neck down.”

Training your resolve

Why we slow down well in advance of our physical limitations – the most widely cited construct being Tim Noakes’ Central Governor theory – shapes Hutchinson’s investigations in Endure. He draws on seemingly death-defying feats of human endurance, from days of dehydration in the Arizona desert to an ultra-runner continuing for 85.5 hours without sleep, to show much more is possible, but found the most surprising example in the capacity to simply hold our breath.

“As runners, we experience oxygen as a limiting factor,” he says. “We’re running hard, panting, and feel as if we cannot get enough air. But to what extent is this real? To try and understand, I looked at free-diving where they dive 100m below the surface and back on a single breath.”

The current record holder in static apnea – or breath-holding – is France’s Stephane Mifsud, who in 2009 managed to stay submerged in his local pool for 11:35mins. Mifsud likened the pain towards the end as lying on a searing barbecue grill. “That’s a great example of the difference between being short of breath running and on the verge of losing consciousness,” Hutchinson says. “Or the difference between a warning sign and a stop sign.”

If this example underlines just how much psychological scope we have for improvement, can we train this resolve? How did Smith, for example, push beyond one Ironman to complete 10 continuously? “By remaining positive – and having a laugh,” she says. “You will have moments when you want to – and probably will – cry, but laughing is essential and makes a huge difference to your mental state.”

If this sounds overly simplified, Marcora would smile wryly in agreement because he’s certain there’s still much to be gained by researching the benefits of motivational self-talk. “It’s a technique people can learn,” explains Marcora, who is working with the British Psychological Society to develop a resource, resist-stopping.co.uk, that’s focused on managing the difficult moments during a race.

In a 2013 study, Marcora headed a group of researchers that prescribed a fortnight of motivational self-talk to 24 participants in cycling time-trial-to-exhaustion tests. They concluded that the reduced rate of perceived effort was statistically significant when compared to the control group.

“It’s about replacing negative internal dialogue with positive, but you need to practise so it takes less cognitive effort to implement,” Marcora explains. “We gave them a list of words to choose from, but it’s important the motivational statements are relevant to the individual.”

How to beat perception of effort

Professor Samuele Marcora suggests that monotonous mental tasks results in stronger athletic performance. Why is down to a build-up in the brain of a neurotransmitter called adenosine. This is the stuff that accumulates when you’re deprived of sleep and has been linked to the feeling of mental tiredness. Hence caffeine, which blocks adenosine receptors on neurons, makes us feel awake and is often used by triathletes to boost performance.

Marcora thinks that consistently flooding the brain with adenosine by engaging in mundane mental tasks can cause neurons to build up a tolerance, meaning that your perception of effort goes down for the same level of actual effort.

According to Marcora, training with mental fatigue is similar to training with extra weight. It’s hard but, once that increased load’s removed, you can run stronger, faster and longer. That’s why once or twice a week you should train after work rather than before. Marcora’s currently developing an app that’ll elicit the right level of boredom and difficulty to tap into his psychobiological model of fatigue.

How visual clues can affect our perception of effort

If effective self-talk relies on deliberate practice, then external, subliminal factors may also provide a psychology boost. Two of Marcora’s partners for the initial study, Anthony Blanchfield and James Hardy, also joined the Italian for research into how non-conscious visual clues affect our perception of effort.

In one experiment, 13 individuals were subliminally primed with happy or sad faces as they cycled to exhaustion. Not only did those who saw smiles cycle for longer, they also did so at a lower rate of perceived effort (RPE). A similar result was obtained when action words, such as ‘go’ or ‘energy’ were flashed up, when compared to inaction words, such as ‘stop’ or ‘toil’.

This thinking can be expanded. As triathletes suffer through the Double Brutal, could the beauty of Snowdonia keep them nourished? Smith also cites eating real food and wearing the right kit as fundamental components of her challenge. If she isn’t irritated by ill-fitting garments, or repulsed by sickly gels, it follows that her perception of discomfort can be reduced.

More research is taking place into ways to train the brain for endurance. Walter Staiano from the University of Valencia, implemented mindfulness practices, including the popular app, Headspace, for six weeks with Denmark’s national junior handball team. Versus the control group he found improvement on all the cognitive and physical tests, from faster reactions and more correct answers, to better agility and decision-making on the court.

Noel Brick at the University of Ulster has also looked at the role of associative and dissociative techniques, finding that learning when to mentally switch on and off in a race can be productive.

“The fundamental idea is that any endurance race requires a sustained focus because we have to overcome a strong inclination to slow or stop,” Hutchinson says. “It can be mentally fatiguing and later in the race we’ll slow without meaning to.” Put another way, if the brain can be trained to overcome this, we should stay on pace better, and it’s the same principle Marcora is working on as he develops a phone app for the Ministry of Defence that will provide audible cognitive tasks for forces personnel as they run or march.

3 Pain-reducing psychology tricks

Easy-to-apply techniques that are proven to reduce pain and boost speed…

1.Smiley, fast triathletes
Triathlete Ross Edgley received acclaim not only for becoming the first person to swim around Great Britain, but for the incredibly positive way in which he did it. And, according to research, Edgley’s positivity made things easier, with studies showing smiling while training distances the athlete from their bodily sensations.

2. Train to the beat
The disassociation effect of music can deafen that voice in your head telling you to quit, but ensure you choose the right tunes. Sports psychologist Costas Karageorghis, says that songs up to 150bpm is good for hard efforts but aim for around 90-120bpm during low-intensity sessions.

3. Find a friend
Training with friends not only increases chances of sticking with a training plan, it also helps you to dig deeper. The competitive element of swimming, biking or running again distracts you from bodily sensations, leading to extra effort and greater results.

Brain stimulation

Training the brain is one approach, but what about just desensitising it? While this might conjure visions of Grand Tour cyclists swigging pain-dulling spirits ascending Mont Ventoux, just last year a World Anti-Doping Agency report found widespread use of the painkiller Tramadol among the peloton. Despite being monitored, the narcotic is not on WADA’s prohibited list.

“There have been a bunch of studies showing a 2% performance improvement in cycling time trials if you simply take paracetamol,” Hutchinson says. “It’s an instant shortcut, but what’s the point? You make the finish line closer.” As well as entering an ethical maze, there are also health risks to consider, such as potential liver and kidney damage, or the prospect of a drowsy cyclist falling off their bike.

Electric brain stimulation, or transcranial direct current stimulation (tDCS), is another area that may have the capacity to alter perception of effort, and while might sound a Frankenstein concept, is a very present prospect in sport.

Ironman champ Jesse Thomas was part of a Red Bull experiment in 2016 that saw “at least 17 devices stuck to my body … and that doesn’t even count the brain stuff – there’s another 30 wires there”, as he prepared to push the pedals on a static bike in the StubHub Velodrome in California. While more research needs to be done, peer reviews found eight of 12 studies of tDCS showed performance benefits.

“I find the technology, and the fact these things work fascinating,” Hutchinson says. “But I have misgivings about what it means in the context of sport. That said, I don’t want to speak from a lofty perch of purity. It’s not as if I’m refusing to use sports nutrition or wear the latest running shoes.”

An essential life-giver

If zapping an athlete’s brain gives an endurance edge, it also sounds inherently risky. Perhaps we should grant more sanctity to our natural perception of effort as a life-preserving biological safeguard, and leave well alone, but that doesn’t have to equate to accepting the status quo...

“Everyone can think of people who’ve developed an unhealthy relationship with exercise,” Hutchinson says. “However, for 99% of people, being able to find the motivation to keep trying to push to new places as you get older is a life-giver.

“It’s easy to allow parameters in life to become set and not to push out of our comfort zones. As an adult we have choice, and most of us stick to things we’re familiar with. [But] not letting our body and minds atrophy is healthy.”

For Smith, striving athletically simply provided a better alternative. “Growing up I experienced some hard times,” she says, “and years of self-abuse followed. I was trying to self-destruct and prove myself to the people that had let me down. The ultra-world has given me a place where I can do it in a healthier way.”