Made for a Marathon: The Science of Long Distance Running

What drives people to run a marathon? Join Hayley Birch as she tackles 26.2 miles, aided by science.

We moved into our flat over a year ago. Not a single picture has been hung. We haven't painted or wallpapered and it took us 13 months to put up a shelf. Redundant audio formats sit, blanketed by dust, in the same box they arrived in. I know it's supposed to be a joint effort but, really, it's mostly my fault. When I signed up for my first marathon, I didn't anticipate the impact that three-hour runs would have on my weekends or pretentions to homemaking. By the time I signed up for my second marathon six months later, I was of the view that weekends were reserved for running and to hell with picture hooks.

Now, don't get me wrong, I go to great lengths to avoid DIY. But as the door clicks softly behind me in the darkness, my body braced to meet the biting cold, I'm not convinced that this is procrastination. Aged 16, I made a £1,000 bet with my dad that I'd run a marathon one day. Aged 30, stumbling over frozen mud tracks, my focus narrow in the dim light of my head lamp, I realise that excuse has long expired. Perhaps marathon number two is all about my goal time? I don't know. After everything, my target of 3 hours 45 minutes seems less important than it once did.

By the time you read this, I'll be recovering from the Brighton Marathon. What I've learned is that running a marathon isn't about running a marathon. I mean, it is and it isn't. I'll explain what I mean later. But I began by asking what it takes to run 26.2 miles – are hard work and determination enough, or is there something else? Something you're born with?

I always say I hate the winter mornings, but there's something about being out before the rest of the world wakes up.

0:00:00

I pull into the car park at Loughborough University's School of Sports, Exercise and Health Sciences in a state of mild panic. Having driven past the motorway exit for Loughborough on my way from Bristol, I've barely made it onto campus in time and am due for my VO2max test any minute. I'm dubious about what the test – which involves cycling to the point of exhaustion – can tell me about how fast I can run 26 miles, and worried about what a poor result could do to my mental state ahead of next week's half-marathon. I'd hoped to send off a mouth swab in the post and get my DNA probed for marathon genes, but one of the genetics experts here has persuaded me that, when it comes to gauging my potential, a bog-standard test of endurance is going to reveal more than any DNA test currently can.

My legs quivering, my feet soaked. There's many a Sunday I've returned to pack my trainers with newspaper.

Half an hour later, following flustered introductions and a wardrobe change, I'm on an exercise bike in a pristine sports lab, receiving instructions from Ben, the sprightliest PhD student I've ever met. Ben is super-enthusiastic about his research and has bags of experience conducting VO2max tests, albeit on obese people. Consequently, the heart rate monitor he asks me to strap around my chest is a little on the loose side. When I complain, he ties a knot in it. Four knots later we're ready to go. My task is to keep the number on the electronic display in front of me – my pedal rate – between 60 and 80. For the first few minutes this proves a doddle. I'm hitting 70 bang on. As I pedal, I can see the computer to my left creating wiggly graphs based on my outputs.

Made for a Marathon: The Science of Long Distance Running

The computer is telling Ben the rate at which my body is taking up oxygen, a rate that's increasing rapidly as the workout becomes more difficult. My performance in this test could be revealing, as my marathon pace will depend on how efficiently my body can use oxygen to break down food and release its energy. All the moisture seems to have left my mouth and, as I try to lick my lips under my facemask, the resistance goes up a notch. Although Ben pours on encouragement, my resolve starts to fail and I grind to a halt after 17 minutes or so, having reached my limit: my VO2max.

Ben is printing out my results when genetics expert Jamie Timmons turns up to see how I've performed. Jamie is a self-confessed cynic. When we met on Skype a few weeks ago he went to great pains to remind me of the various ways I could crash and burn in the marathon. "It's not as simple as 40 per cent environment, 60 per cent genetics," he warned me in his soft Scottish accent. "It depends how much you screw up the environmental factors." Never mind my genetics, he said, dehydration could mean I don't even finish. Encouraging.

When Ben tells him I achieved 50 ml per kg on the test he seems mildly impressed, but with a curl of a smile he tells us he once got a score in the 70s. This would have put him in the same league as Bradley Wiggins, according to Ben's celebrity-based scoring system. I wonder whether he was "born with it". He asks whether I feel as if I gave it my all and I mumble something about the stress of the test and having the university photographer sticking a camera in my face. He mimes playing a tiny violin.

Over an al fresco lunch on a too-chilly September afternoon, I try, unsuccessfully, to coax some straight answers out of Jamie. What percentage of my score, I want to know, is down to my genes? Jamie has worked with data from the so-called HERITAGE study, one of the classic studies in exercise genetics, which asked, essentially, whether the particular set of genes a person inherits has a big influence on their response to exercise. Of 481 participants, from 98 families, who had their VO2max tested, some made massive improvements in their VO2max over 20 weeks of training, others modest or none. It's impossible to know where I started from my current score, but I'm assured by Jamie that some people could never get to 50. "Ever." Some even get worse.

In the HERITAGE study, inherited factors accounted for as much as 47 per cent of the variation among participants' VO2max responses to training. So my genes, I suppose, are about as important as my training. But Jamie wants to add a caveat: maybe not everyone will benefit from the same 20-week training programme. This problem is one that really comes to bother me as the marathon draws ever closer. It boils down to the irksome fact that we're all different. So no matter how I approach my marathon training, I'm always thinking: "How do I know this is going to work for me?"

Can I run 3:45? Before I even ask my next question, I know Jamie's going to dodge it. I want him to make a prediction about my marathon time based on my score. "Um," he begins, pausing to let the fizz from his Coke bottle subside. "The correlation between that figure and your performance is so poor that I could give you a time that's plus or minus an hour. So it's no use to you." The trouble is that even two marathon runners with the exact same VO2max score won't finish together – the score sets their maximum oxygen uptake, but one runner might be able to sustain a level closer to that maximum for longer. Genes, I assume, are at least partly responsible for such differences. I try to press Jamie on which genes, but while he's convinced that having the right genetic profile is at least half the battle, he dismisses many of the studies linking aspects of athletic ability to solitary 'magic genes' as nonsense.

Rather than picking out his favourite genes and attempting to prove that they predict performance, Jamie has been taking a bigger-picture approach, using gene chips to do the picking. His chips, plastic cards that each combine hundreds of genetic probes, are pocket-sized experiments. With them he can spot patterns in the activity levels of genes in a human muscle cell. In one paper, he pinpointed 30 genes whose patterns predict how a person responds to endurance training – whether their VO2max shoots up or barely changes.

Yet in the very same paper, we're warned against ruling out any gene from playing at least a minor role in adaption to exercise. It seems over-cautious to me. But as Jamie points out, "If you think about it, if you have 30 genes and each one speaks to another gene, and they speak to another one…" Then any of my genes might be involved. I'm starting to see why he wouldn't just give me the DNA test.

We return to Jamie's office, where he stands upright at his Swedish-style, chest-height desk, to search Google for a tool that predicts marathon times. Unsurprisingly, there's nothing that stands up to Jamie's scientific scrutiny – or even mine – and those based on my 5 km times suggest that I should be able to run a marathon in under 3:30, a prediction that yields an audible snort from me. After meeting with resident nutrition and fluid experts whose advice I interpret as 'don't do anything on race day you wouldn't do in training', I leave, none the wiser about whether I can run my goal time and frustrated with science for failing to answer my questions.

0:42:03

After my Loughborough trip, I bask briefly in the glory of a 1:39 finish at Weston-super-Mare's sunshine-soaked Grand Pier Half Marathon. Briefly, because I then discover via online rankings that well over 2,000 other women, many of them decades older, have run faster than me over the same distance, just in 2013, just in the UK. Extended research reveals that my previous marathon time of 4:02 (on a hilly course!) wouldn't even gain a 55-year-old a 'good-for-age' classification. I briefly contemplate attempting to crack 3:45 in 25 years, after whatever havoc kids and the menopause will wreak on my body, and resolve firmly to get the job done at the next opportunity.Run for it

Then, only a week later, some ill-advised cross-country practice sets off an old hip and knee problem and I'm confined to the swimming pool for an entire, miserable week, silently cursing the girl doing wobbly backstroke all over my lane. Between swims and newly prescribed torture – sorry, physiotherapy exercises – intended to straighten out my wonky hips, I continue my frantic search for answers. I read 26 papers on exercise genetics. I finish David Epstein's The Sports Gene. I devour Adharanand Finn's Running with the Kenyans and, soon after, Haruki Murakami'sWhat I Talk About When I Talk About Running.

Despite warnings about 'magic genes', I'm intrigued by the genes linked to endurance running. One that keeps cropping up is ACTN3 – when a fellow runner tells me she took a test for it at the London Marathon I immediately turn to my genetics reviews. Supposedly, the two copies of ACTN3 that you inherit from your parents determine whether your muscles contain the fast-twitch fibres of sprinters or the slow-twitch fibres of endurance athletes. Magic gene? Predictably, it's complicated.

To compare people with different genes on equal terms, scientists would need to subject hundreds to the same elite-level training programmes. Unsurprisingly, this hasn't been done. And while it seems the 'sprinting' variant might be linked to sprinting ability in white runners, the majority of Jamaicans have two 'sprinting' variants regardless of ability. So how are we supposed to know what marks out the Usain Bolts of the world?

Made for a Marathon: The Science of Long Distance Running

The ACTN3 theory doesn't really pan out for Kenyans either. Kenyan athletes, who have won seven of the last ten Boston Marathons in both the men's and women's categories, are the masters of distance running. But having tried and largely failed to account for the Kenyan phenomenon through genes, ACTN3 included, some scientists have turned from nature to nurture to explain it, citing diet, training camps, altitude and aspirations of a better life as evidence. It's a seductive notion, because it opens up the possibility that any of us, given an elite athlete's training schedule and meal plan, could achieve greatness (or at least a 3:45 marathon).

For a while, I'm suckered in, until I read some reviews by exercise scientist Ross Tucker at the University of Cape Town. What I come to realise is that just because this gene or that gene, or those five genes, can't explain the Kenyan phenomenon, it doesn't mean that another 50 or 500 can't. It's just basic science. You have to eliminate all the other possibilities in order to accept, tentatively, what remains. So to accept that training and diet are what make a Kenyan – or me – run fast, you have to eliminate all the genetic components first. With so many to eliminate, the task seems hopeless.

Seeking a more straightforward approach to the question of inheritance, I call my mum to quiz her about our family history. I wasn't brought up to be sporty – I was always terrified by cross-country at school – and mum is baffled at any suggestion that her parents or grandparents might have been involved in sports, answering only that they were "working their fingers to the bone, just to get by". On dad's side, there are a couple of cousins who run and he used to be a fine swimmer himself, but I can't trouble him with questions now. The cancer, or at least the mental torment it inflicts, has kept him in bed these last few months.

When I crossed the line at the Worcester Marathon, my mum and brother were waiting for me, without him. But it was dad who put the idea in my head, with his £1,000 bet. I miss our calls. "Have you been running?" he'd ask. Every time. "Dad, I'm always running." I realise now that he was never really asking about the running. He was asking about my state of mind. If I wasn't running, something must be really wrong.

By now, I've become disenamoured of the scientific method as a means of answering my questions. Questions which, it's increasingly apparent, I don't even want to know the answers to.

Not long after signing up for the Brighton Marathon, I came across a convincing article about gene regulation that encouraged me to hope that the activity of whatever genes are involved in marathon running would be kicked up a gear by my gut-busting, five-day-a-week training schedule. I started to imagine my genetic profile, rather than being inscribed in chromosomes of stone, as more malleable, like Plasticine. But now I keep coming back to what Jamie told me about his 30 genes, the ones involved in VO2max response: their activity levels may vary from person to person, but hard training doesn't change how they behave. "They've already been pre-set." If he's right, some people are just born with genes that mean they'll respond better to a marathon training regime.

It feels like by searching for genes that define my capabilities as a human being, all I'm doing is narrowing my horizons. Perhaps, regardless of hard work and gritty determination, I'll never be able to run a decent marathon. Because if I'm honest with myself, all this is not about what makes a good marathon runner. My questions are more personal: "Can I run 3:45?" and "Is that all I've got?" What if all the hours spent pounding the streets don't make a shred of difference? All of that training eating into time with friends, visits with family. The fact that I don't call or visit often enough (what's enough?) is already a source of pit-of-the-stomach guilt.

It's odd how my brain works. Even as I worry that my genes won't let me run 3:45, I worry that they will. Without a clue what my DNA is doing for me, I swing between frustration at the unknown 'upper limit' and fear that my mildly impressive aerobic capacity score hints at mildly impressive hidden talents – fear, because talent means no excuses. And all of it is so intangible. After days at my desk, and evenings working on my wonky hips, I'm finally able to run without pain. I figure that I've spent too long ignoring my more tangible physical attributes. But that's about to change: my next appointment is with a biomechanics expert.

1:23:43

The athletics track at the University of Bath is deserted. Students are holed up in the nearby sports café consuming an unusual amount of salad. Hunched over my laptop, I feel old and stupidly self-conscious. I've come to find out whether my short legs, wonky hips and flat feet are any hindrance in my attempt at a 3:45 marathon. I imagine they must be. They're definitely contributing to my escalating physiotherapy costs. I drain my coffee, leave the tracksuited people to their discussions about modern pentathlon, and head off to the biomechanics lab, where I'm due to meet Polly McGuigan.

Eager-looking students are huddled around a computer in the corner of the lab, which is like a small sports hall and comes complete with a space-age-looking treadmill and a couple of comedy skeletons. (Polly later mentions that she has, on occasion, entered the lab to find the skeletons in compromising positions.) While we're talking, a girl called Emily is getting wires and sensors taped to her right leg. She looks like she has some kind of bionic limb. The experiment involves her walking repeatedly over the pressure pad embedded in the floor, to reveal how her foot distributes pressure during movement. We pause every now and again to watch.

"That's what all the fancy footwear-selling shoe shops are using now to determine which pair of shoes you should wear," Polly says.

"Yeah, but I'm quite sceptical about how they're using them," I reply.

"Good..." whispers Polly, pleased. "That's very wise scepticalness."

Over the phone a month earlier, Polly and I got talking about barefoot running. The idea is that running without the bulky heels of a pair of trainers forces you to land forefoot or midfoot first – because landing heel first would hurt. This means that you run more like humans presumably did in days of old and, potentially, faster. It's a theory pioneered by Harvard's barefoot running enthusiast, Dan Lieberman, and one that the running press has latched on to. Now biomechanics experts everywhere are doing their best to prove or disprove it.

Polly, who did her PhD in horses' legs and keeps referring to my calf as my "shank segment", demonstrates the extra spring you supposedly gain from planting your forefoot first. "I mean, if you think about walking around like this" – she does the exaggerated tiptoe of a cartoon villain across the lab floor – "you feel springier than if you walk around like this" – she stomps around on booted feet. She explains that, in theory, landing forefoot first brings the elastic tendons in the leg into the system earlier, eliminating the hard shock of landing heel first and saving some energy in the bounce. "In theory," she reiterates, with a slight snigger.

Made for a Marathon: The Science of Long Distance Running

Most people are heel strikers, if the research is to be believed, but it's a fuzzy area because, as Polly tells me, it seems to depend on how fast you're running. At higher speeds, more of us switch to a fore- or midfoot strike. It's possible, even wearing trainers, to change your style, but I want to know whether there's any point. Will it make me faster or, more importantly, less injury-prone?

Polly has agreed to check my running style. Watching myself running on the high-speed video recording is odd, like being disembodied. I don't know what I was expecting, but I look… pretty normal. Yes, I'm clearly a heel striker, but at this stage in my training, Polly advises against making any changes. It all looks fairly comfortable, she says – I'm even "springy" for a heel striker. Mental images of me galumphing along like a lost pony begin to dissipate.

I think about how my leg architecture, wonky hips and all, and my inferior running style are just manifestations of my genes and my training, like my VO2max. As far as the genes are concerned, they're akin to finely tuned instruments, each one playing a minor part in some grand genetic orchestra. Really, though, as someone who knows relatively little about music, all I care about is that the overall effect is pretty, not what the individual notes are or how the musicians are interacting with each other. So as far as I'm concerned, it sounds fine.

2:05:58

In the afterword of Running with the Kenyans, Adharanand Finn hears David Rudisha's 800-metre world record at the London 2012 Olympics described as "almost spiritual". This strikes a chord with me. Watching it, I was moved to tears. Rudisha's pace was blistering, but the overall impression was of warm honey falling from a spoon. That's how it feels sometimes too. When the pace is quick but easy, when form flows, when the mind feels at a certain distance from the body, when it's early and quiet, and there's only the sound of breath, and feet flying.

There are those days and there are days when I have to count each heavy step to carry myself home. There are more of the second type of day, but whatever, I keep doing it. Probably because I'm crazy. Being crazy or somehow addicted to running is something that I worry about quite a lot. I mean, there must be a reason that the idea to run a marathon stuck in the head of 16-year-old me, that I feel the need to structure my entire life around the pursuit of a physical goal. Only I must have edited that reason out. Now it's obvious: the question has never been "What makes a marathon runner?" or "Can I run 3:45?" It's always been "Why do I run?"

All this is going through my head at 5.30am while I'm preparing for a Skype interview with Australian neuroscientist Anthony Hannan. We've set up a call to talk about neuroplasticity – the ability of the adult brain to rewire and remodel itself in response to life experiences. I'm hoping he's going to tell me that my training is going to reprogram my brain to make me a better runner.

Anthony appears on webcam as fresh as a daisy, beaming in from his office at the Florey Institute in Melbourne, where it's mid-afternoon. We talk for a little while about Anthony's own marathons – he's run London and Paris – and about brain-derived neurotrophic factor (BDNF), a protein released in the brains of mice when they run, apparently causing new brain cells to grow. Though he says the studies haven't been done, he thinks there's reason to believe that constantly activating the neural circuits involved in running, through regular training, might expand those areas of the brain. He also agrees that there's an addictive quality to running, or exercise generally, and that some people, due to their genes, are probably more prone to that addiction. But what really gets me thinking is his work on Huntington's mice.

Fourteen years ago, while working at the University of Oxford, Anthony was part of a team who showed that exercise combined with cognitive stimulation – activities designed to boost thinking, concentration and memory – helps to delay the onset of Huntington's disease in mice. This discovery was astonishing at the time, since Huntington's had been held up as an example of a genetically inherited disease, a fatal neurodegenerative disorder caused by one errant gene. No one expected that environmental factors, like exercise, would make any difference. But at the Florey, as it's affectionately known, Anthony and his colleagues have gone on to show that it's not just the movement disorder in Huntington's that is delayed. The emergence of dementia in Huntington's is postponed, and depression-like symptoms are corrected. What's more, BDNF and its brain-cell-blossoming effects seem to be central to the whole business. He says other neurological and psychiatric disorders may also respond to exercise: Alzheimer's, Parkinson's, schizophrenia.

Transcribing the interview later, I linger on what Anthony said about the brain being completely embedded in the body. "It's not this separate, dissociated organ. If you have a healthy heart, healthy cardiovascular system, healthy immune system, which all talk to the brain very closely, then you'll have a healthier brain." I wonder if he's indicating that we're all mentally deteriorating in our own ways and that a little exercise could help us all. I hope so. Inadvertently, Anthony has also started to address my other question, about why I run. It's my mind perhaps more than my body that benefits from the 50-km-a-week training programme. I know what I have to do next: find a shrink.

2:49:25

At the end of November I run my fastest ever 5 km on a pitch-black freezing-cold course, in denial of a sniffle. My training has been going well, but I'm half-convinced the result is down to mental strategies deployed during the race – an idea I got from Duncan Simpson, a psychologist at Barry University in Miami. He's not what you'd call a shrink exactly, but when we met on Skype our conversation quickly descended into a pep talk/counselling session and I decided to give positive self-talk a whirl, even if it did feel a bit like ditching the science for self-help magazines. Duncan assured me there's good evidence to back up the use of psychological skills in runners and said that I'd need to practise these before the marathon. "If you just turn up on race day and expect to be able to cope with pain, or negative thinking, and you haven't dealt with it in training, you're not going to be able to." So throughout the 5 km race I try to catch my doubts – "I've gone off too fast", "My legs feel like lead" – and swap them for more encouraging thoughts. "It's okay, you're just feeling fresh", "What's 5 km to a marathon runner, hey?" I'm just practising, having sandbagged around the race because of the sniffle, but as I cross the line and stop my watch, it announces: "New Record!"Top ten tips for a first-time marathoner

The next day, despite the personal victory, I feel like crap. The sniffle has developed into a full-blown cold, not to mention the fact that my dad passed away two weekends ago. The morning after it happened, I pulled on my tread-worn electric blue shoes, opened the door at my parents' house and headed out on an undulating 15 km run. As I often do, I started out thinking I'd take it easy, give myself a break, but slipped quickly into a steady rhythm. The hills that had looked insurmountable when I'd surveyed them from the car seemed to fall away beneath me. There were tears but I returned feeling, as I knew I would, a little better.

Made for a Marathon: The Science of Long Distance Running

Besides talking to my editor, I've barely done any work today. But between funeral arrangements, constant nose-blowing and exchanging miserable emoticons with my other half over Skype, I've purchased a new pair of running shoes online. In the last couple of weeks, I've clocked up nearly 100 km, including last night's personal best. It's not because the marathon is looming. This is just how it goes. Between life and work, and love and death, comes running. To continue with such a demanding regime under the heavy weight of grief might seem to some like punishment. On the contrary, it's self-preservation.

I'm already convinced of the effects of exercise on mood and Duncan has confirmed that exercise is linked to emotional wellbeing, as well as preventing depression and anxiety. Flicking uninterestedly between one social network and another, I remember that he's just written up a study on exercise addiction, and that one of the criteria he used to define addiction is the use of exercise to modify mood. I retrieve a copy of the paper from my email and immediately scan to the methods section for the addiction test, which was taken in the study by a bunch of triathletes.

I take the test and score 23, which, it turns out, is at the top end of "strongly committed" (24 equals a high risk of exercise addiction). When I message my husband, Jonny, to tell him, he replies, "That figures," before joking that he should take a test for computer gaming addiction. I swiftly adapt the exercise test. Jonny scores 14, but admits that he's "not being that honest". Unwittingly, he's pointed out an important limitation: the answers are self-reported. In the discussion section of the paper, the authors suggest that "addicts" may give higher answers in order to seem more committed. It's hard to know if I've fallen into this trap, but I am satisfied with the thought that I am the most committed exerciser I could be without being addicted. Not addicted, but probably a bit nuts: it seems an appropriate diagnosis for someone training for a marathon.

3:33:20

When you're training for a marathon, you make up reasons for why your body isn't performing the way you want it to. You didn't stretch properly after your last run. Your shoes are getting old. It was windy. Muddy. Below zero. You're still congested after that cold you had two weeks ago. Um… It's January? The truth is you're tired. You're really, really tired. By Friday, a rest day, the lethargy of the week's training – the hills session, the night at the track, the core strength exercises, the stretching, the 15 km 'easy' run at 6.30am – it takes its toll, and you start to doubt whether the 30 km run you have planned for the weekend is a good idea. You reappraise your training schedule. You wonder if you should swap one of those Sunday long runs for a swim, to reduce the impact on your niggling ankle. You wonder whether a few long runs are really going to make any difference to your fitness and if, in the end, it's all about confidence. Then, just as you're about to update your Google Calendar, you realise what you're up to. Slacking off. Ha! Think again, cheater. Come Sunday morning, you rise at 7am to force down a bowl of sugary porridge. No one drags you out of bed. The niggle is barely noticeable. As you check for the third time that you have your keys, you realise it has started to drizzle. By the time you're two kilometres down the road, the drizzle has turned to hailstones. You curse out loud as you're pelted by balls of ice the size of small planets. Your bare arms sting. If you had any sense you'd stop and hide in that bus shelter. But you carry on.

It's difficult to explain what's going on in the head of someone who has committed to training five, sometimes six, days a week, to running hundreds of kilometres every month. It's difficult to explain, even when that person is you. I've thought for a long time about whether it takes a certain kind of person to run a marathon. Whether there's some genetic signature that underlies not only the right physiology but the right personality.

The final piece of advice that Duncan the psychologist gives me is to write down why I'm doing the marathon. "What are the things that you really value and how can you connect those deep personality values with what you're going to do as a runner? Because that's what's going to help you when everything else goes to shit and it hurts like hell and you want to stop. Those are the things that are going to keep you going."

It takes me several days to write my list. Meanwhile, I read a couple of papers about some scale that psychologists have developed for categorising marathon runners' motivations, but I don't seem to fit neatly into any of their boxes. The marathon is a personal challenge, yes, but I'm not one of their "personal goal achievers" (and there isn't a box marked "DIY avoidance"). What I come to accept is that the race itself is just an excuse for all the rest of it. For venturing outside more than once a fortnight, for staying on top my life, for preventing each week from disintegrating into a sea of unanswered emails, unwashed coffee cups and unopened post. For guilt-free time out. For solace.

One of the points on my list goes like this: "I love to train. I love to train more than I love to race. But if I don't achieve my goal in the race it will make all my training seem futile. Values: I enjoy order and structure in a life that can be and has been chaotic recently. This is what training gives me, as well as a sense of wellbeing. I don't want all of that to be for nothing though. There has to be a goal and an opportunity for achievement to create motivation for training."

I think, wrapped up in the guise of a psychological tool, there are great big hulking nuggets of truth here. It seems kind of stupid that I had to go through this whole charade to be able to write down the answer to a question I didn't know I was asking. But what I found out is that running the marathon is not about running the marathon. It's about everything else.

3:45:09 — Epilogue

It's Sunday afternoon, and I'm submerged in a steaming hot bath. In the room next door, my husband, my friend Zia and her boyfriend are sniggering over having conspired to play 'Chariots of Fire' through the bathroom speakers. I remember the creep of first light through the curtain this morning, the eight hours I had lain awake, plagued by the neighbours' bedroom antics and conscious of the task ahead. I remember the last, excruciating push for the line and the embrace I received from a stranger as I swayed and struggled to stay upright on the other side. I remember pebbles against my back on Brighton beach, watching my calves twitch visibly.

Today I ran a marathon in 3:45. I wonder what more my genes will permit, but I quickly rein in the fantasy. After all, there are other reasons for running.

Contributors

References

  • Adharanand Finn's experiences in Iten, Kenya, described in Running with the Kenyans, make for a fascinating exploration of the cultural factors that contribute to the Kenyans' success.
  • How does your running style affect your speed and your risk of injury? No one study on this subject provides all the answers but this 2011 paper addresses the link between running style and finishing time in a marathon.
  • In What I Talk About When I Talk About Running, Haruki Murakami gives his personal take on running and its influence on his life and work.
  • A study on motivation that asks what drives runners to endure pain and personal sacrifice to achieve their marathon-running goals.
  • In Jamie Timmons's work with gene chips, he identifies genetic profiles – not just single genes – that can help identify people who respond well to endurance training.
  • According to sports scientist Ross Tucker and his colleagues, few would dispute that important aspects of sporting success, such as biomechanics and metabolism, have at least some genetic basis. But actually pinning down the genes responsible isn't that straightforward.

This article first appeared on Mosaic and is republished here under Creative Commons license. Mosaic is dedicated to exploring the science of life. Each week, it publishes a feature on an aspect of biology or medicine that affects our lives, our health or our society; it tells stories with real depth about the ideas, trends and people that drive contemporary life sciences. Mosaic is published by the Wellcome Trust, a global charitable foundation that seeks to drive extraordinary improvements in human and animal health. It covers subjects that fit with the Trust's mission and vision, but isn't limited to the research the Trust funds. Images by Alain Limoges,Ricardo Bandiera, Jacson Que Rubin, Shutterstock