How to get your race-day nutrition right

How to get your race-day nutrition right

Author: Women's Running Magazine

Read Time:   |  February 22, 2017

How to get your race-day nutrition right

When preparing for a long race like a marathon or half-marathon, we naturally pay a lot of attention to our training, ensuring we clock up enough miles to stand us in good stead on race day. And while we know it’s sensible to practice a nutrition strategy to avoid any stomach issues on race day, many of us are still confused about what to eat and whether or not gels or energy drinks should play a role in race-day nutrition. Some sports nutrition companies will recommend taking gels every half an hour in a long race, while nutrition experts generally say we’ve got enough stored fuel to keep us going for around 90 minutes before we need to take anything extra.

When running legend Kathrine Switzer completed the Boston Marathon in 1967, there were no gels, bars or drinks. She ran her first marathon on nothing but water. It was the same for Joyce Smith, who was the women’s winner of the London Marathon in 1981.

And some people still run without extra fuel. “There are an awful lot of people who run half-marathons, and to some extent marathons, without ever using gels,” says John Brewer, Professor of Applied Sport Science at St Mary’s University.

To fuel or not?

So should you fuel up during a race or not? Expert opinions vary, but ultimately it depends on whether or not you’ve consumed enough carbohydrates before race day, and how far and fast you’re running. Brewer says: “I think it’s useful to look at what the body has when it stands on the start line in terms of its energy, and as long as a person’s diet has been sufficient, and by that I mean has plenty of carbohydrate in it, then most runners stand on the start line with enough glycogen to get them to around 17-18 miles’ worth of running. In terms of a half-marathon, one could argue there is no real need to take on a gel because you have enough energy to get you around the course.”

Emma Barraclough, senior nutritionist for Science In Sport, agrees it’s important to consume sufficient carbohydrates beforehand. She recommends looking at your carbohydrate intake the night before and the morning of the race. “If you’ve got an early morning start for race day, have your evening meal not much later than 6pm, so you’ve plenty of digestion time and then your breakfast in the morning two to three hours pre-race,” she says. “The recommendation for carbohydrate intake is 8-10 grams per kilogram of body mass beforehand (throughout the day). The app My Fitness Pal will count grams of carbohydrates, protein and fat. If you’re not sure of your food amounts, and what’s in your food, it’s a good way to do it.”

If you weighed 55kg for instance, you’d have around 480-500gm of carbohydrate the day before your race.

Brewer advises not getting too hung up on weighing foods. “For most people, and it’s certainly true for a half marathon, race-day nutrition is about making sure that there is carbohydrate on your plate,” he says. “You probably had a pasta meal and all the carbohydrate snacks like bananas, wine gums, jelly babies and sultanas. It is about looking at your plate and making sure there is rice, pasta or potatoes to give you that sufficient carbohydrate boost. If you’re running a marathon, you’ll burn about 3,000 calories. A half-marathon is about 1,500 calories. We just have to make sure our portions contain a bit more carbohydrate than normal.”

Carb training

Some people find it hard to consume too many carbs, but your body can be trained to get used to it. “We know that the gut does adapt,” says Barraclough. This means you can practise consuming more carbohydrates in the weeks leading up to race-day.

Nutrition doesn’t have a one-size-fits-all solution – we’re all different and our needs vary. Some people can run well without gels or drinks, while others prefer to know they have extra fuel if needed.

However, if you’re going for a personal best in a half-marathon, you may want to look more carefully at your nutrition strategy. “If you’re really going for a half-marathon PB, it’s actually a short enough distance for caffeine right from the start,” says Barraclough. “So I would have a gel with some caffeine in it half an hour before the race starts.” Barraclough recommends taking gels on average every 30 minutes if you’re aiming to run a half marathon in around 90 minutes. “Even if you’re going at a reasonable pace, you’re probably not needing more than two or three gels within the half marathon race itself,” she adds.

Whether or not you take gels or energy drinks depends on how well you can cope with liquid. “You need to be able to tolerate the volume of liquid in your stomach,” says Barraclough. “If you have got to take 500ml of a sports drink to get the same amount of carbohydrate that you get in a 60ml energy gel, that’s a lot of fluid jostling around in your stomach. Gels are the most convenient way to make sure you get energy in.”

Caffeine buzz

On a longer race like a marathon, avoid taking a gel with caffeine at the start, as a caffeine buzz could mean setting off too quickly. If you need fuel, take gels every half an hour, after an hour into the race. If you had breakfast more than three hours before the start of the race, you may get hungry. “A bar beforehand might be a good option, and the sports energy bars are designed with this in mind,” says Barraclough. “Avoid bars with more nuts and fibre.”

How to get your race-day nutrition right

During the marathon, take a drink that contains electrolytes, to replace lost sodium. “You want to avoid Hyponatremia, where people have drunk too much water and over-diluted the salt levels within their system. If you use an electrolyte drink, it should minimise that risk,” says Barrclough.

Energy reserves

You can also conserve energy by running more slowly. “Most carbo gels only have enough carbohydrate for one mile of running,” says Brewer. “It’s usually about 120-130 calories. You can spare carbohydrate by running at a slow pace and pacing properly. If you set off at a slow pace, you could get to 20 miles before you run out of carbohydrate. If you’re going for a time, you don’t want to set off at such a slow pace that you’ll miss the time, but you have to be realistic and run at the pace based on your training. There is a balance between knowing what you’re capable of and what your body requires.” Brewer adds: “If you set off a comfortable training pace then so long as you trained for the marathon, that should be the pace where you are still burn a mixing of fat and carbohydrate. If you set off a bit slower than that, in the early stages you may well spare carbohydrate which will give you more to use at the end of the race, so in the end, your final finishing time might be quicker than if you set off faster.”

Women's Running Magazine

NMA’s 2020 Lifestyle Magazine of the Year, Women’s Running provides expert advice on gear and training, motivation from your favourite runners and the latest running news.

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