Get those miles in

A current trend is to do high intensity gym training to get fit quickly. That won’t help with a marathon. You have to get mileage into your legs because the key to success is having what I call an ‘aerobic base’.


That doesn’t mean you need to cover vast distances. For those who are new to marathons, you need to build up to 45km (28 miles) a week on average, with that distance split over several runs.


Plan a big(-ish) run

You need to experience a long run before the marathon itself. Less experienced runners tend to do a longest run of about 29km (18 miles). You want to do that about three to four weeks before the marathon.

If you are new to the marathon, you don’t want to be doing that a lot because you cause muscle damage, muscle fatigue, pain in the legs and so forth.

Need to know...

  1. Don’t run distances that are too long in training.
  2. Training increases the number of capillaries in your muscles and makes your heart larger.
  3. Refuel your body with food within 60 minutes of a training session to speed up recovery.

Increasing the ‘miles per gallon’ of your body is key

You want to be able to use less energy per footfall. As you train, you get more capillaries in the muscles to get oxygenated blood to them.

Your heart gets bigger on the outside, and the cavities inside – the ventricles – also enlarge. So per beat, the heart can eject more blood. You get increased levels of aerobic enzymes and increased mitochondria, where aerobic metabolism takes place.


Plan faster runs into your weekly training

We’re talking about the kind of running where you can’t quite hold a conversation. You could run in the ‘tempo zone’, as we call it, for 40 minutes non-stop, which is pretty hard. Or you could do it in 10-minute blocks with a short recovery in between.

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© Cathal Duane
© Cathal Duane

Eat those carbs to help you prepare

The big fuel for your body is carbohydrate. It also helps during recovery. You need to ensure your diet is carb-rich, with plenty of foods like pasta, and bananas to help recovery. You are causing muscle damage when you run, so you need protein to help with muscle repair – things like chicken, fish and pulses.

If you refuel your body within about 60 minutes of stopping your run, you get metabolic recovery and all the fuels are restored within 12 to 14 hours. Leave it longer than an hour and you’re looking at anything up to 72 hours for recovery.

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On marathon day, eat what you can keep down

Things like muesli or porridge with fruit are good as they release the energy slowly. If you eat fast-energy-release foods you get an instant hit, but you might run out of energy.


Pace yourself to avoid pain

The two biggest causes of pain in a marathon are when you lack preparation – you’ve not run enough miles in training – and poor pacing in the marathon itself. The former results in just having to run slowly throughout. The latter leads to pain.


Most runners go too fast at the start of the marathon and will burn energy too quickly. This will lead to them running out of energy too soon and having to slow down. It then becomes an uncomfortable run.


Andy is a Senior Lecturer in Science Communication at the University of the West of England in Bristol, Programme Leader of the MSc in Science Communication and an award-winning journalist