Nutritional Advice for Marathon Runners

London Marathon 2008 - Dorset Web Team

As your training and excitement builds, whether you’ve run five, one or none yet, each Race is unique and special, and demands your commitment – especially if you want to enjoy it as well as just finish!

This page is provided by George Petry MBA Dip.(Nutrition) a Bournemouth-based nutritionist at Nutri-Balance Health in Poole and Barnstaple (North Devon), to help visitors to this site with some important nutritional advice to help prepare for their big day.

Over the years George has run 24 marathons, and countless half marathons, 10k races and other running and cross-country skiing disciplines, so he knows from experience what works and what doesn’t. His nutritional advice below is so important for all 3 phases of the run: pre-marathon preparation, during the race, post-race recovery.

Surprisingly, the advice is essentially simple and sometimes obvious – yet so many people don’t bother…..and suffer accordingly. So lets put your challenge in perspective. You are about to enter a short and very intense phase of your life (between 2½ and 5 hours) that will sap every ounce of energy from your body and mind. You will expend more physical and mental energy in those few hours than you do in a whole week. In preparation for the run you will [hopefully] and sensibly push yourself to build strength and stamina over weeks if not months. After the run you will probably collapse in a heap with a silly grin of well-earned smug satisfaction, shivering aching muscles, blistered feet and salt-covered skin.

So what can you do now (nutritionally) that will reduce your agony (or fear of agony) and raise your performance before during and after the run?

The real basics - what to eat generally:

Eating a healthy balanced diet will provide you with all the nutrients you need to take part in your favourite sport or activity. This means eating a wide variety of foods, to get the balance right.

As a runner, the best way to get the most out of your sport is to:

Timing of meals around workouts is just as important as what you eat if you want to keep your energy levels up. For the first two hours after exercise, muscles can refuel their glycogen stores twice as fast as normal so it's important to eat carbohydrate-containing foods as soon as possible after a workout or exercise session.

Good sources of energy

Carbohydrate is the most important fuel for energy, so you should eat lots of foods (at least 55% of your diet) that are rich in starchy carbohydrates. Carbs are the nutrient most easily converted into ATP (the chemical product in our bodies from the nutritional breakdown of carbs, fats and proteins for the production of energy). Protein is stored in the body as muscle; fat is stored in the body as fat and carbs are stored in the muscles and liver as easily obtainable glycogen.

Many different foods contain carbohydrate. The richest sources are bread, rice, pasta, cereals and potatoes, but other foods also contain useful amounts, such as: fruit, vegetables, beans, pulses, yoghurt and milk.

The more you exercise, the more carbohydrate you need. The actual amount you need depends upon the type of exercise you're doing, the intensity, duration and frequency of the exercise, and your fitness level. This becomes so important the closer you get to race day and the more you train on longer runs to build your endurance. The bigger the glycogen stores in your liver and muscles, the longer you can perform. If you exhaust your glycogen stores, the body will start to breakdown the fat stores, and when these are depleted, then it will start to breakdown protein in the muscles. Examples of this body fuel consumption are seen in photographs of concentration camp victims.

Protein and sport

We need protein for our muscles to grow and repair themselves. Protein is also a source of energy. The amount of protein athletes need has been a topic of huge debate for many years because people who are very active, especially those who train frequently, generally require more protein than those who don't.

However, most people in the UK eat more protein than they need, so even top athletes should be getting enough protein to meet their needs. This means there should be no need for you to increase the amount you eat of foods rich in protein and there is no need to buy protein supplements – unless you are also looking to bulk out. If you are………then skip the marathon – you will hurt.

Remember, you should be able to get all the protein you need by eating a variety of foods.

Drinking for sport

If you get dehydrated it can stop you getting the most out of your activity, so it's essential you drink enough. To help keep you hydrated:

And remember that the fluid we have when we're exercising should be on top of the usual 1.5 litres (6 to 8 glasses) we need every day to stop us getting dehydrated.

If you're exercising for longer than 1.5 hours such as pre-Race training, try to eat a high-energy snack such as a banana or some dried fruit before you start or during exercise (if this is practical). If you can't manage this, you might find it useful to have some diluted fruit juice or squash to help give you energy.

It's not usually necessary to drink sports drinks just because you're active. Fruit juice mixed with water, well diluted fruit squashes, or juice drinks will hydrate you and give you some energy. There are basically 3 types of sports drinks:

  1. Carbohydrate drinks, rich in carbs, these should be drunk BEFORE and event to help replenish and store glycogen reserves in the muscles and liver
  2. Isotonic drinks, designed to be taken while running to quickly deliver glucose to the muscles for extra energy
  3. Hypotonic drinks, contain few carbs. These are designed to replenish water and mineral salts lost from the body during the race, to prevent dehydration pains

Mineral and isotonic drinks may be useful, and the Lucozade brand promotes such drinks. Try them to see if they work for you. Electrolyte replacement during a run is useful [many race organisers offer these at watering points], and AFTER a long run is vital. A bottle of Lucozade Sport or similar may be a valuable quick top up. Try some during your pre-race training.

Running and supplements

You should be able to get all the nutrients you need from a healthy balanced diet - and remember that taking supplements won't make up for not eating well.

If you have a medical condition that restricts your diet eg food allergies, Coeliac, or food intolerances, then you must seek professional advice. If your GP is unable to help, then you can contact George on 01202 707072 for a food intolerances screening. If you mention this website, he will offer you a 15% discount.

What to eat in the final stages of training

Now you're in the final stages of training then it's best to:

But you don't need to increase the amount of protein you're eating. Even though you're running the marathon, eating a balanced diet will give you enough protein to meet your needs. Current evidence doesn't support the idea that performance can be improved by taking protein or amino acid supplements.

Practical meal tips:  Here are some suggestions for what you could eat to give you a balanced diet on a typical day in the last couple of weeks before the race:

Breakfast

Snack

There are lots of healthy snacks available when you're preparing for the marathon, such as:

Lunch

Snack

Pick a snack from the list above or try:

And don't forget to keep drinking, you could have some fruit juice or a smoothie.

Dinner

Supper

Bowl of cereal and low-fat milk or soup and roll

The week before the race

At this point you need to focus on topping up your glycogen stores by increasing the amount of carbohydrate you're eating.

Carbohydrate is the most important fuel for energy. It's stored in the liver and muscles as glycogen and if these stores run low it can often causes tiredness when you're running.

The bigger the glycogen stores in your muscles, the longer you can perform. So this is particularly important for running marathons. Base your pre-marathon meals and snacks on carbohydrates, such as: bread, rice, pasta, cereals, potatoes, fruit and vegetables.

Avoid drinking large amounts of tea, coffee or alcohol. These have a diuretic effect by increasing the amount of urine produced by your body.

The night before the race

Tonight you should aim to eat as much carbohydrate as you can to make sure your glycogen stores are at their maximum.

Aim to eat lots of starchy carbohydrates such as rice, pasta, bread and potatoes. But this is the one time that it's NOT a good idea to go for wholegrain varieties. This is because high-fibre foods take a long time to digest and fill you up, which means it's hard to maximise your glycogen stores. So for this final meal, avoid foods that also contain a lot of fibre.

You can top up your meal with a low-fat high-carbohydrate snack such as a cereal bar, a slice or two of malt loaf, or a couple of fig rolls.

Remember, even if you do sport regularly, this advice only applies to the night before the marathon.

Practical tip: If you’ve ever run behind a runner who got their pre-race diet wrong, and seen diarrhoea running down the back of their legs….you’ll understand this warning.

DON’T try something new that you haven't tried before. Rehearse everything – especially the “night-before” meal. You DO NOT want bowel problems during the race – because you will be nervous and excited enough before the whistle blows. The last thing you want on the day is an upset stomach and no where private to stop.

On the big day

Despite any pre-race nerves you may have it's important to eat breakfast on the morning of the race. Pick something you enjoy eating that is rich in carbohydrates and low in fat but that isn't too bulky or heavy.

You could choose:

And drink a glass of fruit juice (diluted if you prefer), a smoothie or an isotonic sports drink.

What time you eat breakfast is up to you, but it's a good idea to make this at least two to three hours before the race to give you plenty of time to digest your food. Some experienced runners say a couple of cups of coffee are useful before the race because the caffeine acts as a stimulant. It never worked for me…..the excitement was usually stimulation enough.

Lastly; if you include meditation in your life, then spend 20 minutes meditating before you go out, gently focussing your energy, and relaxing your body whilst preparing your mind to drive your through that inevitable wall around the 21 mile point.

After the Race

Well done. You are now overjoyed the race is over and you are weary, legs hurting, blisters a worry perhaps, and probably getting very cold. If you’ve run a marathon before, you’ll know that the best things to do now are:

I should say avoid alcohol…..but hey……just don’t drink too much. You are on empty and the alcohol will go straight into your bloodstream

Keeping hydrated

Dehydration and heat stress can stop you getting the most out of your body, so it's important that you drink enough.  Water accounts for 80% of our bodies. During the marathon (and training) our muscles generate internal heat. In order to prevent the body temperature from rising too high, we sweat. Water and salts are excreted through the pores of the skin to cool the body, and are therefore lost to the body to continue the cooling system. Therefore water must be replenished regularly.

It’s around the 16 mile point you will have notice how dry you feel, and by then you will realise that you must keep topping up with water. With 10 more miles to go and your dreaded “Wall” approaching as your glycogen energy reserves become consumed, a healthy hydrated body will help keep you going.

Symptoms of dehydration include: general discomfort, headache, exhaustion, aching limbs and apathy. Yes….sounds like “The Wall”.

Remember that during training, you need extra fluid on top of the usual 1.5 litres (6 to 8 glasses) we need to stop us getting dehydrated.

So make sure you're well hydrated BEFORE you start the race. And during the race, grab a drink from the drinks stations along the course, if these have been provided. Around half a pint (225ml) every half an hour is a generally accepted guide.

Don’t drink too much water because this can cause problems too. More than 3.5 litres (6 pints) while sweating profusely risks low blood sodium levels (hyponatremia) which lead to clear symptoms that include: nausea, cramp, fatigue, drowsiness, muscle twitching confusion, seizure and possibly coma. Hence the value of Hypotonic drinks after race to replenish the mineral salts.

For short bouts of activity, it's fine just to drink water or diluted fruit juice before and after you exercise. However, when you're running the marathon you'll be exercising for a long time so you will probably find that carbohydrate or isotonic/electrolyte drinks will help keep you going.

And finally, best of luck!

George Petry MBA Dip.(Nutrition) - Nutri-Balance Health

Nutri-Balance
George Petry

For any further nutritional advice, please contact George Petry on:

Nutri-Balance Health
Clinic: 01202 707072
Mobile:  07831 258789
Email: george@nutri-balance.co.uk
Web: www.nutri-balance.co.uk