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Ed's Story: Marathon running and diabetes

Meet Ed

Ed Straiton ran his first London Marathon in 2016.

He was diagnosed with Type 1 diabetes when he was 8. Now 25, Ed has been training hard in the run-up to the event and will be fundraising for Diabetes UK.

Interested in his personal journey from here to the finishing line, we asked him to share with us how he manages his diabetes, his diet, and how he’s preparing for such a tough endurance event...

Marathon running and diabetes

 Ed Straiton"I’ve always been active – it’s part of my diabetes control,’ says Ed. ‘In preparation for London, I’ve already done a couple of half marathons and a triathlon. For me, running is what works. If you’re thinking about taking up exercise, do what you enjoy. I have grown to enjoy running – but, if you enjoy swimming or cycling, do that. Whatever you do, it all helps!

Benefits of running

"The benefits I gain from running and training include...

  • more self-confidence
  • larger friendship groups from clubs
  • more connections at work through having common ground
  • a very firm bum!

Eating and running

"I roll out of bed at 5.45am – I pull on my clothes, test my bloods (usually around 5 upon waking), and eat a banana and either a small portion of cereal or half an SiS energy bar. A seven-mile run before breakfast requires fuel, although I often find that much of the energy comes from the meal I’ve had the night before. My evening meal is always balanced and I’m careful never to skip meals. Before my run, I put the rest of the bar in my pocket as insurance in case my sugars go low due to the exercise.

Generally, running drops my sugar levels by about 1 mmol per mile, which is why I eat a banana beforehand. They are ‘magic’ as they have 20-30g carbs in them – I give myself 1 unit of insulin to balance this. High-density energy bars provide the rest of the energy. I’ve worked out that seven miles of running can change my blood sugar as much as 7 mmol, which is why eating close to beginning a run is so important.

On Sunday I tend to do a long run, and my food prep starts the night before. I will eat three times the normal amount of complex carbs on the Saturday evening – for example, 200g of brown rice (uncooked dry weight), meat to provide protein and then vegetables. Breakfast on Sunday is 60g (uncooked dry weight) of porridge oats with two crumbled dark chocolate digestives in it (my weakness!). I drink 1.5 litres of sugar-free squash and let it all settle for an hour, before I head out.

I calculate that my body requires insulin for approximately three-quarters of the food I have eaten – the other quarter serves to keep my blood on a plateau while I train.

When I run for more than an hour, I need to refuel and hydrate along the way. I carry 500ml water with me and use SiS energy gels (22g of carbs per gel) which I take strategically along my route. For a two-hour run, I’d have one energy gel on the hour mark.

After the run, I do a blood test and use my pump to raise my insulin levels. The main thing I remember when training is that my body needs fuel - starving it means that my performance is compromised and often I don’t see the improvements that I want. Eat smart and cleverly, and be prepared. A little bit of thought and planning will help to deliver better results.

Diet, training and food

"I follow what I know works - eating right. Everything we eat has an impact on us. I am careful that most of what goes into me has a purpose. I believe in everything in moderation; I’m not a crazy health-kick person, if I want some chocolate, I have it, but a KitKat for me is a special occasion (and I enjoy it all the more!).

For snacks I tend to choose fruit, all of my meals are typically balanced, limiting any or all simple sugars. I recently converted to black coffee from lattes as I was finding these had a detrimental effect upon my blood sugar levels – it’s a question of working out what is right for you.

Foods that help my running - and those that don't...


  • Bananas
  • Sugar-free squash and electrolyte drinks
  • High-performance energy bars
  • Complex carbs (brown rice, porridge)
  • Milk - I find it hydrates me quickly


  • Pizza
  • White carbs
  • Drinks like Coca-Cola
  • Anything that spikes my blood sugar

Training and insulin

"As my blood sugar generally drops when I train, I reduce my insulin before a run. For any run under two hours, I remove my pump. Through experience, I can predict how my body will respond and adapt accordingly.

Eating prior to a race

"Lots of people ‘carb load’ before a race, which is fine, but personally I find it hard. For previous races, I have ‘loaded’ for two days beforehand, raising my intake of brown rice to massive scales. However, I then find I really struggle to keep my blood sugars under control, which makes me feel unwell.

On race day I go out hard – in the case of the Reading half marathon, my blood was 6 before I started, and 1 hour 40 minutes later it was 5.8. Clearly, it does work, but I don’t feel the best. For this marathon, I will load for two days before, keeping an eye on my glucose levels and aiming to keep it under control. The night before, I will increase my complex carb intake like usual, and breakfast on race day will be porridge and a trusty banana.

During a race

"I don’t drink any energy drinks during the actual race, I go for gels and SiS cereal bars. This works, so it’s the routine I’ll be sticking to. Any endurance event requires you to refuel. If I feel my sugars dropping, I neck a gel or a bar. The 60g bars have 40g of carb in them, plenty to try and correct it. I don’t stop unless my body gives way and luckily I haven’t ever got to this stage.

I have researched my bloods before, utilising a one-mile circuit to test the ‘one-point drop’ theory out - run a mile, do a blood test, run another, do a blood test. I will not be testing during the marathon, but I will test just before it, and have ordered a FuelBelt which means I can carry everything I need with me. Usually, I can figure out what is going on in my head and I won’t be stopping unnecessarily as I am quite competitive!

After a race

"After a 10-14 mile run, I eat something sweet, like a bar of chocolate or a flapjack. It’s important to begin to replace the calories I’ve lost. Following that, I tend to eat a couple of big meals (with high protein and complex carb content) to help re-fuel me."

This article is one man’s own personal experience and his management of his diabetes may not be appropriate for you. Before making any changes to your diabetes management, discuss with your healthcare team.

Training room

You'll find tips and training plans on our marathon training and diabetes page.

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