The emotional impact of sugar as running fuel

Do you ever feel yourself hitting an energy wall just over an hour into an exercise session? Running experts advise taking onboard some kind of fuel if you’re going to run for over 75 minutes. I’m generally terrible at doing this, but I realise I’m going to have to experiment with some kind of running fuel before the London Marathon. When I ran the Ultra Marathon, I was happy eating things like wraps and chocolate bars because it was such a long, slow run. But a marathon is different. So last time I went for a run, I needed to grab something to eat en route. The mistake I made was neglecting to realise the emotional impact of sugar as running fuel.

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Sugar as running fuel

I went for a long run a couple of weeks ago and really felt my energy levels depleting after I’d run for around two hours. I had intended to buy some sort of running fuel to stick in my jacket pocket. But when it came to this week’s long run, I’d forgotten. All I had in the house was a box of the children’s sweets that they often accumulate and rarely eat. The only thing that was vegetarian was a stick of rock, so I broke half of it off and stuck it in my pocket.

I took a small bite of the rock after I’d been running for about 45 minutes. From then on, I’d nibble on it around once every half an hour. And my legs felt strong. The energy wall I’d hit the previous week didn’t seem to be bothering me.

The problem was the emotional impact of sugar as running fuel. Every time the sugar started to wear off, I felt miserable. I started to think that the time I’d had off training over the past couple of weeks was too much. I wasn’t going to manage the marathon. My time would be terrible. Training on the hills was no good for a road race. And on it went.

In fact, it carried on long after I’d finished running. By the end of the afternoon I was slumped on the sofa, making a half-hearted attempt at working. I’d convinced myself that I was too tired to go out that evening. And, that I couldn’t handle the social situation. What if there was no space at the table with people I know when I arrived? What if I got drunk and swore at someone? Or worse still, I didn’t have the confidence to speak to anyone at all? I cancelled my plans.

Why do I think this was the emotional impact of sugar as running fuel?

With hindsight, it’s not the first time this has happened. I look back on other long runs I’ve done and the hideous emotions I was feeling towards the end and directly afterwards. The last time I ran the London Marathon, I fuelled it on Skittles, along with the energy drinks being given out on the course. As the run went on, I got progressively more sad that none of my family or friends had come to watch me. At the beginning of the run, I had been perfectly happy without them. Then at the end, there were no trains home. Which wasn’t a big deal really, but it seemed it at the time.

I’ve done some research and it seems that taking sugar onboard causes fluctuations in blood sugar. The sugar high is soon replaced by a drop in blood sugar, so each time you take sugar on board you end up with energy peaks and troughs. The troughs are thought to cause low moods and make you more emotional.

Alternatives to sugar as running fuel

Advice from both Map my Run and the BBC suggests fuelling on high-sugar options. These include sports drinks and sweets. I’m fairly certain though that these won’t work for me. As well as carbohydrates for energy, many websites suggest taking on caffeine. I’m going to try out some natural fruit, nut and seed bars that are easy to eat. I like the sound of the ones that Sarah reviewed as part of her fuelling experiment series.

Additionally, I may try to get hold of some coffee beans. Caffeine definitely gives me a boost, so if I can take that on without sugar then I think that would be helpful. If you have any other suggestions then please do let me know, I’d love to avoid the emotional impact of sugar as running fuel without forgoing the benefits of fuelling properly.

Emotional impact of sugar as running fuel | If you run long distances, you'll be aware of the need to fuel properly during your run. Many experts advise taking sugary energy drinks, bars or sweets. But have you thought about the emotional effect of all the sugar? Could the psychology of being mentally stronger without the sugar highs and lows improve your times? #running #distancerunning #marathontraining #diet #sugar

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  1. Fuelling with sweets does sound couner-intuitive – I’m surprised the BBC suggest high-sugar options. Would something like dried mango work instead? That would be my fuel of choice! Good luck with your training x

  2. Wow! Who would have thought sugar could affect you quite so badly? I think there is a time and a place for sugar in exercise, but it should defyinky be used sparingly when you need a quick energy burst – probably not for a marathon! Thanks for the mention. I’m very happy with the Go Bites and intend to stick with them. I just need to work out how often to take them!

    1. That’s great to know. I’m not going to buy the go bites in bulk just yet but I’m definitely going to get something similar by tomorrow morning when I do this week’s long run!

  3. I have the same problems with sugar, i have found since having children i am less able to balance my sugar levels, i get ‘spaced’ much more easily, hope you find the ‘right’ fuel for you!!