On Sunday morning, thousands of people will undergo a ritual familiar to anyone who has run the London Marathon. The extremely early wake-up call after a fitful night’s sleep. The enormous breakfast bowl of porridge, or multiple slices of toast, to store energy for what lies ahead. Vaseline smeared on the nipples, inner arms and thighs. The last-minute trip – or rather trips – to the loo. Excitement, fear and adrenaline at the start. A glorious wall of noise from the hordes of spectators lining the course. And then, 26.2 miles later, an overwhelming buzz of success.

Last year, the London marathon celebrated its one millionth finisher since its first event in 1981, yet the demand for places continues to swell. This year, more than 250,000 people entered the ballot: 39,000 will toe the starting line. Whether you are one of those about to pin a number to your chest, or you suspect that you might one day catch this mysterious bug, here are 10 points to guide you to a good marathon – from someone about to tackle her eighth ...

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How long do I need to train for?



The first step is to choose a realistic training plan and a realistic timeframe. Such plans usually range from 12 to 20 weeks, but even those for beginners tend to assume that you are already capable of running three times a week. So if your running shoes have been left in a musty cupboard for years, you need to get to that point first. The London marathon ballot results come out in October, so if you bag a place for 2018, you need to spend October to January gently building up. Then do your research and find a plan that is right for you and which has been devised by a reputable coach, either online, or in a book or magazine. Don’t, however, be a mindless slave to this plan. Marathon training is a fine balance between pushing yourself, and recovering properly. Feeling knackered is normal, being unable to get up in the morning is not. Niggles are par for the course and a few days’ rest may sort them – proper injuries may disrupt your plans. Accept that, and listen to your body.

How much commitment does it take?



Let’s not beat about the bush. Marathons can be brutal. It’s a long-term commitment. There will be freezing Sunday mornings when your alarm shrills at your groggy head and your body is a bundle of mysterious aches, facing the prospect of a training run longer than you have ever tackled before. You will have to alter your schedule to sneak in extra miles, perhaps running to work, running at lunchtime or forgoing social occasions. There will be moments when you question your sanity. This all takes support, sometimes lots of it. If you have a partner, they must, for all practical purposes, sign up, too, whether it’s by having a hot bath ready for your return, or by happily acquiescing to quiet Saturday nights in. A running buddy training for the same race is invaluable, as are running clubs, or look online and find a forum for people with similar goals. Or, of course, join the Guardian running blog.

Why London anyway? Aren’t there other marathons?



There are – and most have a distinct, special atmosphere. Whether you prefer a big city marathon or something a lot smaller and off road, there’s a race for you. However, I have run marathons in New York (epic), Tokyo (unbelievably friendly), Berlin (flat and fast) and then I’ve run London three times – four, come Sunday. London simply blows the others out of the water. I ran my first in 2014, cynical hack, fully prepared to be underwhelmed. I’ve never experienced anything like it. The support is spine-tingling. Marathon day is a little flashback to the 2012 Olympics, when cynicism evaporated overnight and total strangers shared eye contact – even (gasp!) conversation – on the tube. What’s more, London’s organisation is unbelievably slick. You stagger across that finish line on the Mall, wobble fawn-legged as a kind soul puts a medal around your neck. Seconds later, someone is holding out your bag to you. Yes, your odds of a ballot place are slim, and fundraising for the charity ones is onerous. But if you get the chance: do it. It’s simply the best race in the world.

Setting a goal



It doesn’t matter how fast you can zip round a 5k parkrun, or how much you fancy your chances of smashing a colleague’s personal best: the primary goal before your first marathon should be to finish it. Anything else is just the icing on the well-earned cake. The course of 26.2 miles is – forgive the glaring lack of logic – more than double a half marathon. The cliche that “the race begins at 20 miles” is true. Push beyond that barrier, and suddenly things fall apart – the body cannot hold. By all means use a “race time predictor” on the internet to estimate your time, and aim for that, but remember that is probably a best case scenario. Adapt, and adjust – both before, if injuries threaten – and during, if things don’t go right on the day. And hey, remember, the first time you race any distance, it’s a guaranteed personal best.

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How long should your longest run in training be?



People get fixated on this, but really, the best advice is to not to worry about distance but to work to a maximum “time on feet”. Whether that takes you to 18, 20 or 22 miles is irrelevant – the point is that you need to recover from that before you run the marathon itself. Most people do this three weeks before, but four is fine, and might be better. Pushing yourself further into unknown territory, just so that you know you can, will only risk still-tired legs on race day. And when your stomach fills with dread at the prospect of 20 miles in grey drizzle, remember that everyone feels like this. Those slogs, on your own, with no adrenaline, no rest, and no crowd support are the hardest part. Get your training right and race day will genuinely seem easy in comparison.

What should I eat?



Before his first London marathon, the former 10,000-metre record holder Dave Bedford had four pina coladas, countless beers and a large curry – having entered the race for a bet a few hours before. Needless to say, this is not the optimum strategy. But how seriously you take your training nutrition depends on your goals. If you surveyed regular runners, one of their top reasons for running would be “so that I can eat more cake”. By all means, reward yourself within reason – and don’t go overboard on “recovery shakes”. Almost all sports nutrition products are simply a more convenient way in which to replace lost carbohydrates and protein – particularly important for recovering muscles. But really, proper food is better. The week before your big race is a good time to try and eat as healthily as you can, drink minimal alcohol but plenty of water, and sleep as much as possible

Yet wonderful though it is to have a legitimate excuse to binge on pizza, try not to go overboard

What about carb loading, and gels during the race?



Around two to three days before the race, you can start carb loading. When we run, we burn fats – of which we have a near-limitless supply, regardless of body shape – and carbohydrates. The latter, in the form of glycogen, starts to run out after about 90 minutes. Carb loading ensures that your glycogen levels are at their peak when you start. Yet wonderful though it is to have a legitimate excuse to binge on pizza, try not to go overboard. You don’t want to give yourself stomach problems. And make sure, whatever you have for breakfast on race day, that you have tried and tested it before a long run.

During the race, your glycogen tank will start depleting. If you don’t top it up, you could hit the dreaded “wall”. Whether you replace it in the form of gels, jelly beans, or sports drink (or nothing) is a personal choice but one that it is absolutely essential to practise in advance. Find out what works for you and what your stomach can tolerate. Race day is not a day for sudden random experimentation.

Be the tortoise, not the hare



The waiting is done. Pre-race nerves have settled. You are across the line, and suddenly feel great. The single most important thing you can do now is relax and take it easy. Starting too fast is the most common race mistake. Yes, for the first few miles, marathon pace will feel really easy. It always does, right up to the point when it doesn’t. You cannot wing a marathon. If everything in your training points towards a reasonable goal, you are simply NOT going to miraculously shave 45 minutes off that. Guard against the rush of blood to the head and do not hare off. If you still feel good at 20 miles, then by all means put the hammer down. A negative split – running the second half faster than the first – is one of the holy grails of marathon running, but it’s one even the elites don’t always hit.

You will overcome



What makes a marathon such a challenge is partly the amount of time you spend in your own head. How do you cope with crashing from grinning highs to desperate lows? How do you shut up the voice that whispers, insistently, at 16 miles that there’s no way you can do another 10? By remembering the long training runs when you did it all by yourself. By trusting in that training. And by blocking out the negative voices. There are many strategies for this – counting in your head is one (Paula Radcliffe counted to a hundred when times got tough) or adopting a mantra (my favourite is Commonwealth Games runner Steve Way’s: “Don’t be shit!”). Break the race down into chunks, and take each mile individually. Talk yourself through bad patches, in your head or – why not? – out loud. Now is not the time for self-consciousness. You are a marathoner now.

Enjoy it. Or as much of it as you can



When you cross the finish line, you will probably be elated, exhausted and quite possibly find yourself howling: “I’m never, ever doing that again!”. Until a few days, weeks or months later, when you suddenly find yourself online, credit card in hand, inexplicably entering another one. Marathons can be addictive. I remember waking up the morning after my first and thinking: “Oh my God. I ran a marathon yesterday. I RAN A MARATHON.” It doesn’t get better than that. Until you do it again, only faster.

Facebook Twitter Pinterest London marathon competitors head to the finishing line. Photograph: Anthony Devlin/PA

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