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Fuelling your Marathon - Nutrition for Before, During and After your Endurance Event

You are what you eat. So, to run a marathon maybe you should be tucking into large portions of ostrich (it’s estimated they could run 26 miles in 45 minutes!). It’s not such a crazy idea, being high in protein, low in fat and cholesterol. But it’s a rather expensive option, and you still wouldn’t get all the nutrients you need. As a marathon runner, triathlete or any other endurance athlete the following advice will still be useful, even if you’re friends with an ostrich farmer.

Ostrich head

A balanced, high-quality diet with the right levels of macro- and micronutrients is an essential part of any healthy lifestyle and critical to athletic success. Macronutrients make up most our diet and provide bulk energy via proteins, carbohydrates and fats. Micronutrients are the vitamins, minerals, and trace elements that we need regularly in very small quantities for the healthy functioning of all our body's systems - from bone growth to brain function.

The general rule of thumb from the Eat-Well model is that carbohydrates should make up a third of our daily calories. However, since carbs are an athlete’s main fuel source during training and competition, we need more than people who are sedentary or only do light exercise. Typically, carbohydrate needs will vary from 5 to 10g per kg of body weight per day, depending on the type of training that you engage in. If you know how much you weigh and have a good training plan you can work out roughly how many grams of carbs you need daily:

Carbohydrate needs

The rest of your diet should be made up of: fruits and vegetables (try to eat at least 5-a-day and the more varied the colours, the better range of vitamins and minerals that will be available to your body); protein (2-3 servings daily, dependent on your training volume); and healthy fats (20-30% of your diet).

Protein needs

It is important to get the right balance of nutrients in your diet and everyone’s requirements will be slightly different, so find something at works well for you.

Before Exercise

Exercising on an empty stomach can lead to the breakdown of muscle tissue, as it could be converted to glucose, which in turn can negatively affect your metabolism. So it’s always important to properly fuel your run or workout. There is a general rule of thumb that says you can eat at any point prior to exercise, but closer you leave it, the more simple the food needs to be in order to ensure you can digest it in time to be of use. So, if you eat two to three hours beforehand, your body will have sufficient time to break down complex meals containing plenty of slow release carbohydrates, as well as a moderate amount of protein and fat to properly fuel your body. But if you have to eat less than an hour before your run you would be better off eating something that can be digested quickly, such as fruit.

Good examples of complex foods are:

poached egg on toast
  • Porridge (complex carbs and if made with milk some protein) with fruit (simple carbs and vitamins & minerals - and one of your 5 a day!)

  • Eggs (protein and fat) with wholemeal toast (complex carbs), tomatoes (carbs) and mushrooms (carbs and protein)

  • Chicken (protein), tuna (protein) or egg (protein) sandwich (complex carbs) and fruit (carbs and vitamins and minerals)

  • Bagel (complex carbs) with nut butter (e.g.: peanut, almond or cashew) (protein and fat)

  • Quinoa porridge (complex carbs and protein source) (also suitable for vegans)

During Exercise

It's important to replenish your glycogen stores during runs of 90 minutes or more (anything less than that and you won’t have enough time to digest and process the nutrients). Your body can only store around 2,000 kcals of glycogen and after an hour or so of running, your fuel tank warning light will flicker on unless you frequently top up your carbs. Foods that can be quickly digested are ideal:

  • Sports gels / isotonic drinks

  • Bananas, oranges, or dried fruit such as dates

  • Sugar-rich sweets such as jelly beans/babies

  • Chocolate-covered nuts

  • Honey/jam/chocolate spread sandwiches

Fuel every 45-60 minutes during a long run, with around 30-60 grams of simple carbs (120-140 calories) per hour (equivalent of one banana). During your race it is also important to drink fluids and top up your electrolytes, which are necessary for digestion as well as your muscles, heart and nervous system. Everyone is different and sweats at different rates, so as a guide you should aim to drink between 300-800 ml of fluid per hour.

After Exercise

It is important to replenish your muscles’ glycogen stores as soon as you can after a run, ideally within 20 to 30 minutes, as well as providing your body with protein to help to rebuild muscle and repair damaged tissue. As you re-hydrate to replace water and electrolytes lost through sweat and re-fuel, muscles soak up nutrients and fluids. The hard part about re-fuelling is that runners often don’t feel like eating for several hours after a strenuous workout. This is where recovery drinks can be especially helpful because they are properly formulated for refuelling fatigued muscles and they are easy to get down. Real food alternatives can also provide the right blend of protein, carbohydrates and fat for replenishing depleted muscles after a run:

chocolate milkshake
  • Chocolate milk (protein, fat and carbs)

  • Frozen banana milkshake (that’s my favourite!) (protein, fat and simple & complex carbs)

  • High protein yogurt and jam (carbs, fat and protein)

  • Cottage cheese (protein) on crackers (complex carbs) or with sweet potato wedges (prep this in advance) (carbs)

  • Poached eggs (protein and fat) with salmon (protein and fat) or spinach (carbs) (or both, yum!)

  • Grilled chicken (protein), rice (complex carbs) and steamed vegetables (carbs and vitamins & minerals)

We are all different, so try and find out what fuels and fluids work best for you before, during and after running. Remember to rehearse your fuelling and hydration strategy before your event and don’t try anything new on race day!

#nutrition #marathon #marathontraining #LondonMarathon

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