Fuel for outdoor sports


Trail runner in the mist
Credit: Myke Hermsmeyer


I started off with the title of “nutrition” for this blog post, but decided to change it.

Nutrition for sports and indeed health in general has become an absolute minefield in recent years. Conflicting information abounds on what we should be putting into our bodies to elicit peak performance. While massive amounts of time, energy and money have been spent on identifying the best approach to nutrition a consensus has yet to be reached except in the broadest terms. Coupled with the fact that diet is one of the major factors that impact body image, nutrition is an emotive topic with few concrete answers.

But lucky for me, we can ignore most of that when I am talking about what to pack for outdoors food. Because rather than macro-nutrients, micro-nutrients and meal plans, we are simply concerned about fuel for the body. So rather than weighing up the relative merits of plant-based, paleo, and low-carb diets, we are interested in just a few simple factors:

-Calorie content – lots of accessible calories

-Size/transportability – small, light, robust

-Convenience – no preparation/clean up


Yeah, but why should I care?

Energy gels and chews
Credit: running.competitor.com

As I covered before, in exercise taking place over a period of hours, athletes produce energy via two mechanisms: fat metabolism (the aerobic system) and glycosis (the anaerobic system). Fat metabolism uses fat as a fuel. Body fat is plentiful and calorifically dense, which makes it an excellent fuel source. However, fat metabolism only powers “low intensity” exercise, so the faster/harder you are going, the more energy your anaerobic system will have provide. The anaerobic system uses glycogen as a fuel. Compared to fat, which is effectively limitless in supply in this context, the body can only store a limited supply of glycogen. A run, cycle, cross-country ski or similar session of several hours will easily deplete this store.

When your supply of glycogen is gone, you experience you experience something called “the bonk” and have two options: slow right down to an intensity that your aerobic system can cover 100% or consume accessible carbohydrates.


“The Bonk” aka “Hitting the Wall”

Cyclist sitting on the road
Bonking makes you regret your life choices that led to this moment. Credit: ilovebycycling.com

Lots of people call it “hitting the wall”, but I prefer “the bonk” or “bonking,” because it makes me snigger like a teenager. It is quite an experience. Coming on fast, your brain and body feel like shutting down and you have almost no energy to continue moving. Motivation plummets. Muscle power drops by about 20% and coordination suffers. In my case, I tend to start swearing under my breath, but your method of enjoying the experience may differ. In short, it is quite unpleasant, seriously hampers performance, and is definitely something to be avoided.

The simplest way to prevent The Bonk is through consumption of simple carbohydrates – or sugars. Yup, even though sugar has recently come to be viewed with the same level of distrust reserved for hard drugs, it still has its place as a fuel for endurance athletes.

You can get your sugars from sports drinks, candies, fruits, or whatever you choose. But it’s important to consider just how many calories you need. Running, for example, expends 100 to 250 calories an hour. Depending how hard you are pushing it the majority of this will probably come from glycogen rather than body fat. In terms of fresh fruit alone, 250 calories equates to 2-5 apples or about 1-3 bananas, which means sourcing your calories from fruit would not be practical for a long run. Unless you happen to be running through an orchard. But even then, you have to consider what volume of food your stomach can handle during intense exercise. Accordingly, serious endurance athletes generally use a reconstituted sports drink (such as tailwind), or energy gels.


Energy gels

Gu gels
GU energy gels. Nasty and effective.

To tell the truth, energy gels are fairly nasty and I dislike them. But they work. Essentially, they are a sugar syrup mixed with a few other choice nutrients. They are designed to absorb quickly into the blood stream and raise blood sugars. Some also contain caffeine for an extra performance kick. The most popular brand by far is GU, but Clif also make them and there are many other smaller brands out there, each with its own angle on the concept of accessible calorie intake on the go.
One caveat though, some people find these gels can cause GI issues, so as with anything you take on your outdoors adventures, be sure to test them first before relying on them.


Yeah, but I’m not an endurance athlete; seriously, why should I care?

If you are hiking or taking it slow, then you can pack a picnic and enjoy a much more wholesome method of fueling your body. But even so, it is still good practice to carry a gel or other source of simple carbohydrate. Think of it as a piece of your emergency kit. If something happens and you are out much longer than expected, an energy boost could make a big difference. Really, you don’t want to be worrying about running out of energy if you are already in a difficult situation. Also, if you ever come across a diabetic suffering from hypoglycemia, administration of some simple carbohydrates will resolve the situation almost instantaneously.



Pack some simple carbs with you when you go. This can just be some candies, but sports gels offer a more complete – but less delicious – solution.

So do you use energy gels/chews, sports drinks or other form of sports nutrition? What is your go-to brand and why? Do you find some particularly more palatable than others? Let me know in the comments below!

5 Essential Items for Outdoor Sports

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  • Yachiyo Maruyama

    Have you tried Carbohydrate Loading for race before? So, trendy low carb diet in women.
    but it’s very difficult for athletes, volume of carb hey need in a endurance.

    • Rowan White

      I make sure to pig-out on pasta the night before a big mission or long event, but I am not really sure of the science behind it. That is, I have no idea just how much carbs I should eat or in what time frame.

      I hesitate to talk about nutrition at all, but I do think modern western and Japanese diets tend to be too carb-heavy, especially considering how little exercise most people do. For an athlete, aiming to get your calories from an equal balance of protein, carbohydrate and fat seems to be popular.

  • Naoko Komuro

    When I and Thomas go for a long distance run we do carry some energy gels or at least sports drink. Especially if it’s a race we do make sure we have enough energy to get through. For races we normally check course map and elevation so we know when is the good time to take energy. Knowing the course and elevation helps mentaly to prepare and I often try to take gels when it’s flat so it’s easy to do or before big ups coming up. Sometimes during running I realy feel like not taking gels or don’t want to break my running rythm by putting my hand around in a pocket and opening gels etc, but I try to stick to my plan of when to take to avoid running out of energy later on! I also cut gel’s slit a little bit more to help opening easily. I get cold hands after a while and it gets hard to open those gels.

    Thomas was reserching about those carb load before the race. I think it’s better to have lots of carbs 2 and 3 days before the race to store it in your body but not the day before so the body doesn’t get too heavy. or something like that….

    So when is your next big race, Rowan ;)??!!

    • Rowan White

      I have never tried eating gels in the cold, but thanks for the tip! I also did not realize carb loading 2-3 days before was even possible!

      I am getting more interested in sports drinks because I think they are easier to ingest and they make it much easier to maintain a constant energy level. Have you heard of Tailwind? It seems to be popular and I am going to try it out soon.

      I know what you mean about not wanting to mess around with gels during a race. Not only do you have to reach into a pocket, but gulping down the goop can be quite difficult when you are running hard. That said, I think it is so important to have a nutrition plan and to stick to it. I decided to skip one scheduled gel and try and push through to the end in the marathon I ran recently. I ran out of energy about 7-8 km from the end and probably lost 6 min in total…

      My next race will be a short but steep 25 k in September, a coastal 35 k in October, and then a 50 k in November (although I might cancel this and go for a steep 3-day/100km stage race instead).

      Onwards, upwards!!