The Future of Endurance


Article by BY MARINA KALCINA - The Lateral Magazine

Three athletes training for the 1896 Olympic Games marathon.   Burton Holmes/Wikimedia Commons  (public domain)

Three athletes training for the 1896 Olympic Games marathon. Burton Holmes/Wikimedia Commons (public domain)

As the story goes, Pheidippides ran 26 miles from the town of Marathon to Athens to announce a Greek victory and warn the Athenians of the incoming Persian fleet. This epic run had three notable consequences. The first two were relatively immediate: Pheidippides, who had run 280 miles in the 10 days prior to his marathon, dropped dead from exhaustion. The second: His message allowed the Athenian army to organise their defence, thus defeating the Persians a second time and making Europe as we know it possible.

The third consequence happened centuries later. The first marathon, inspired by Pheidippides' legendary runs, was introduced to the modern Olympic Games in 1896. Fittingly, a Greek man by the name of Spiridon Louis won the event.

Since then, interest in running has been on the rise. The first running boom occurred after the 1972 Munich Olympic Marathon, when a German student, who was not actually in the race, crossed the line ahead of American runner Frank Shorter. This dramatic event is said to have captured imaginations worldwide, and saw 25 million Americans take up some aspect of the sport thereafter. The current running boom has seen an estimated 200 million people worldwide take to the sport in the last five to ten years.

A marathon is certainly on the to-do list of many runners. Perhaps it’s due to the belief that people who have run 42.195km are part of an elite club, the opportunity it creates to make like-minded friends, or the nice pair of quads one acquires from this type of running. Whatever the reason, marathon running in particular has grown in popularity at an astounding rate. In the US alone, there was a reported 47% increase in the number of marathon finishers between 2000 and 2011.

Deciding to run a marathon is one thing; finishing it is quite another. What biological changes does it take to run the mother of all races?

According to Rick Mirabella, owner and founder of Runnez, a research-based indoor running class designed for all fitness levels, would-be marathoners should train their bodies in multiple ways. “A balanced program that factors in all training components including long runs, tempo, interval, and fartlek running, combined with regeneration days, will yield a vast increase in the body’s mitochondria and capillaries,” he says.

Mitochondria, the little energy factories inside our cells, consume oxygen to produce ATP, an energy molecule that allows muscle contraction, and subsequently locomotor activity, to occur. Capillaries deliver oxygen to the mitochondria. Over time, and with the right training, we become more efficient at using oxygen to make ATP rapidly. This occurs through mitochondrial biogenesis, which is triggered under certain physical stimuli – such as the various running types outlined by Mirabella.

Not only does endurance training stock up muscles with capillaries and mitochondria, the left ventricle of the heart also increases in size, meaning it can hold and pump more blood. In addition, endurance runners have more red blood cells, haemoglobin-packed blood and high blood volume compared to sedentary individuals.

What are we left with? In short, a high VO2 max, which is the maximum amount of oxygen that can be consumed and used in one minute. The more endurance training you do, the higher your VO2 max ‒ and the more economically you can run. So, in essence, you increase your pace, and therefore the distance you run, but your level of effort remains the same.

Physical endurance is, of course, an essential part of running a marathon.   Danielle Walquist Lynch/Flickr  (CC BY 2.0)                   

Physical endurance is, of course, an essential part of running a marathon. Danielle Walquist Lynch/Flickr (CC BY 2.0)


For a century, researchers have focussed on the role of the muscles to explain the limits of endurance, and training programs have been built on this knowledge. What the focus has not been on, until recently, is the brain.

“Mental fatigue plays a big role in every sport, notably endurance sports such as running," says Mirabella. "For optimum performance, you need the physical base, but if you have it and still don’t perform to expectation, then we must look to the mental."

In a 2009 study, Samuele Marcora and colleagues found that, just as muscle fatigue has an impact on physical performance, so too does mental work – and the impact is just as large. Subjects spent 90 minutes either passively watching a documentary about trains, or sitting at a computer completing the AX-CPT test, a ‘cognitively challenging task’ that involves responding repeatedly to a sequence of letters. Both groups then immediately completed a cycling test. Compared with the film watchers, participants in the task group found the exercise harder and reached exhaustion 15% earlier.

This means that it may not be physical shortcomings, like oxygen shortages in your muscles, that impact the way you race, but rather the way your brain perceives these signals.

Physiologists have long believed that marathoners run until their muscles are depleted of glycogen, or their legs fail. However, very few marathoners reach that breakdown point. One theory, espoused by sports scientist Tim Noakes at the University of Cape Town, is that the brain acts as a ‘central governor’ when racing, and, to ensure self-preservation, limits our ability to push beyond fatigue.

South African sports scientist Tim Noakes proposed the 'central governor' theory.   Wouter du Toit/Flickr  (CC BY-NC-ND 2.0)

South African sports scientist Tim Noakes proposed the 'central governor' theory. Wouter du Toit/Flickr (CC BY-NC-ND 2.0)

“Anyone who has ever exercised at all realises that a large portion of training physically is ‘above the shoulders’," says Mirabella. "Noakes’ idea about the brain preserving the body by putting a stop to ‘painful’ speeds goes a long way to explain why some people can be in ‘agony’ for a few kilometres, and then kick for the last 100m of a race.”

The 'central governor' theory suggests that we can improve our marathon performance simply by training the brain. It doesn’t seem so far-fetched – after all, we train muscles to increase capillary and mitochondrial density. We train the heart to increase the thickness of the left ventricle and improve oxygen transport. The brain is an organ like the heart – so can we train it, too?

In a 2015 study by the UK's Ministry of Defence overseen by Samuele Marcora, subjects trained on a stationary bike three times per week while engaging in the AX-CPT cognitive task. After 12 weeks, the group that had completed their training without the mental component showed a 42% improvement in their time-to-exhaustion test results. The group that combined physical and mental training improved by a huge 126%.

So according to Marcora, yes, you can train your brain. You train it to tolerate a harder perceived effort by fatiguing it with cognitively demanding tasks. When that mental stimulus is removed, the physical task being trained for seems easier. According to Mirabella, training your brain might be as easy as running after a one-hour drive or a stressful day at work.

Exerting yourself mentally – using either Marcora’s or Mirabella’s suggestions – and following up with a run is designed to simulate the point in a race or marathon when the brain starts to fatigue. Brain training gives the runner practice at pushing through this mental state. But what is actually happening in the brain when we train it, and how is it changing?

According to Marcora, focussing on a monotonous task for an extended period of time causes a build-up of the neurotransmitter adenosine. This is the same neurotransmitter that builds up when you are sleep-deprived. Inducing mental fatigue triggers a flood of adenosine, and, if you do this every training session, neurons and synapses may eventually adapt to keep adenosine levels lower. Over time, the brain’s contribution to your overall feeling of effort stays lower as a marathon progresses. This allows faster running with the same level of exertion.

So is the future of marathon training centred on the brain? That depends on whom you ask. Marcora believes there is nothing left to gain from the traditional physiological way of training, and that innovation in fitness must come from elsewhere. In Mirabella's fitness circle, many coaches consider brain training a gimmick, but he remains open to the idea.

“The bottom line is, we just don’t know enough about the brain, so we’d be crazy to ignore the results of these studies," says Mirabella. "But we do need more research and time. Personally, I’ve been embracing these findings and incorporating them into my coaching. I can’t wait to see how much of an influence brain training has on coaches and athletes 50 years from now."


The smart way to ease yourself out of winter hibernation

As we endure the final few weeks of winter and start to think about the impending swimsuit season, it can be tempting to succumb to restrictive diets and extreme exercise sessions in a bid to get svelte for spring.

But if you've relaxed over winter, experts say there's no point in working yourself into a tizz trying to slim down.

Instead, if you ease yourself back on the healthy eating and fitness bandwagon, you'll get more long-lasting results that will keep you from finding yourself in this situation in future. Here's how:

Celebrate your couch time

One of the worst things you can do for your motivation levels is beat yourself up for having too many Netflix binges in the dreary weather – kindness and self compassion actually go a long way towards motivating you to keep moving.

"Relaxing is also good for your health," Shelley Lask from Body Positive Health & Fitness tells Coach.

"Show yourself compassion if you haven't been as active as you would have liked, and recognise that it's normal for our activity levels to wax and wane through the ebbs and flows of life."

Start slow

A lot of people make the mistake of going too hard too soon, then lose motivation.

"The best way to be active year round is to avoid all-or-nothing thinking and instead include space for flexibility in your physical activity," Lask explains.

"If you're having a busy or exhausting week, but manage to fit in a walk, give yourself a pat on the back for including some gentle movement. Celebrate what you do get done rather than stressing about what you didn't."

Trainer Rick Mirabella from Runnez agrees, suggesting you kick off with three 20-minute movement sessions a week to keep things manageable.

"We have to build a foundation, so I would say spend four weeks with three sessions a week," he says.

"It doesn't have to be crazy. Maybe just do 20 minutes on a cross-trainer or, if you're fit enough, do 20 minutes of interval training."

Use the weather to your advantage

As we head closer to spring, the warmer air can be a wonderful motivator and Lask suggests scheduling active catch-ups with friends to help you continue making exercise a seamless part of your day.

"Organising a walk with a friend rather than a sit-down coffee catch up is a lovely way to enjoy the weather and enjoy some physical activity while still being social," she says.

"Find activities that you actually enjoy and that help you move better and feel good. Try some new activities for variety, such as archery, boxing or laser tag."

Embrace seasonal ingredients

The sun is not the only thing in abundance in spring – there's also a bounty of beautiful fruit and vegetables begging to be eaten.

"Lots of fresh local produce comes back into season as the weather starts to slowly warm up," Kara Landau, Travelling Dietitian tells Coach.

"Some of my favourites include disease-fighting cruciferous vegetables such as cauliflower and broccoli, as well as Brussels sprouts, asparagus and beetroot. I love roasting cauliflower, beetroot and Brussels sprouts and making up a colourful, flavoursome salad."

Don't detox

If you're feeling sluggish after subsisting on pizza and puddings since June, it can be tempting to sign up for a strict detox in a bid to re-set your insides.

But Landau says it's probably not necessary, given your kidney and liver do a pretty good job of detoxing automatically.

"Our bodies are set up to naturally detox themselves, so going on a prescribed 'detox' is not necessarily going to be of any benefit physically," she says.

"Incorporating more whole foods and removing refined and artificially formulated products will be of more benefit to your body going forward."

*Motivation is your best accessory with the Fitbit Alta – built with all-day activity, auto sleep, SmartTrack™ and reminders to move.