My Cart

Fueling the Fire: Success Through Pre- and Intra-Run Nutrition

Not getting the most out of your runs? Maybe proper fueling is the missing key to getting you to the next level.
Fueling the Fire: Success Through Pre- and Intra-Run Nutrition Featured Image

Most runners are obsessed with having all the right gear.

How a shoe feels can make or break your training session or race, and chafing can ruin an otherwise fantastic session. But there’s one tool most runners are underutilizing, even at the collegiate and professional levels.

One of the best tools a runner has? Proper fuel.

As a lifelong runner turned collegiate sprinter, fuel has become central in my racing and training plans to keep me physically on top of my game and mentally refreshed for school. 

Athletes need to pay attention to what they eat immediately before and during activity to minimize fatigue, maximize recovery, and feel their best during a session or race. But there are a lot of different opinions out there and knowing where to start can be confusing.



When we think “energy," we often think of caffeine. There are certainly links between caffeine and performance: moderate amounts have been shown to improve athletic performance. But when you chug a cup of coffee and head out on an otherwise empty stomach, disaster is brewing.

For one, caffeine can cause digestive upset in some athletes, especially on an empty stomach (as anyone who has downed an iced coffee too close to go time can attest). The main issue with relying on caffeine as a source of “energy” is that your muscles can’t access caffeine to fuel them. Caffeine stimulates your central nervous system but doesn’t provide food for your muscles.

Relying on caffeine alone is like pouring kerosene into an empty fire pit: it’s going to light up quickly but burn out just as fast.

Our muscle's main source of fuel? Carbohydrates. Affectionately known as carbs, these familiar friends are the most efficient fuel source we have as they are easily tolerated and quickly converted to energy by our digestive systems. The best carb immediately preceding or during a session is simple sugar.

Yes, you heard me: sugar.

You may think, “Hold on, isn’t sugar bad for me?” Of course, in excess amounts, sugar consumption can have less than desirable effects. But there is an unnecessary fear among athletes around sugar as a tool for training.

At the chemical level, all carbohydrates—including whole wheat 12-grain bread—are composed of sugars. Most sports dieticians recommend approximately 20-60g of carbs per hour of activity. I don’t know about you, but I don’t feel like stopping to have a piece of whole wheat avocado toast in the middle of a tough interval session (nor would I be able to keep it down, in all honesty).

However, simple sugars are easily digested without causing any unwanted side effects.

Enter GU Gels, Chews, and Stroopwaffels

These products provide a quick dose of carbs in an easily-digested, energy-packed combo: maltodextrin, which is made from rice, and good old sugar. As a bonus, the flavours include varying amounts of caffeine from 0-40mg per serving, so you can pick and choose based on the kind of pick-me-up you might be needing that session.

Pairing your caffeine with a carb ensures you can reap the performance benefits of caffeine with fewer potential drawbacks.

Wait, are GUs just sugar?

Nope! The GU products also pack two essential ingredients: sodium and amino acids.

Sodium is essential in maintaining electrolyte balance in your body as it's what you lose the most of in sweat. When our electrolytes are out of balance, we might feel dizzy, tired, and increased muscle fatigue. Basically, the run becomes that much more difficult. The GUs play double duty here in keeping you performing well: they fuel your muscles and help keep you on top of electrolyte imbalance.

Amino acids have been shown to reduce mental fatigue and support muscle recovery. Known as the building blocks of protein, our body needs amino acids for everything from building proteins to balancing our hormones. Our body is unable to make the essential amino acids naturally. A well-balanced diet will cover most of them, but the GU products can give athletes, who may need more of these acids, a boost.

What fuel is right for me?

Each GU product has its pros and cons. I like to consider these pros and cons in three parameters: portability, chewability, and deliciousness.

Portability refers to how portable the product is on a long run. Could I fit it in the teeny tiny pocket of my run shorts or on a run belt? Chewability refers to how easy the product is to consume on the go: am I risking choking or drying out my mouth? And finally, deliciousness is measured not just by taste, but by the experience of consuming the fuel. If the texture is funny, it’s a no from me.

The gels are the most portable by far.

The packaging is compact and because of the gels’ inherent squishiness, they can be jammed into a pocket or run belt with ease. They also get a gold star for chewability as they’re somewhere between a solid and a liquid, so they’re chewable but not drying. The major con for me is deliciousness. I love the taste of my favourite flavours, but if you’re not a fan of the texture of, say, honey, gels might not be your favourite option. They can also be quite sticky if an open gel is left in a run belt or a bag.

Gels are my go-to for pre-race and between intervals.

My personal favourite flavours: salted watermelon, birthday cake, and campfire smores.

The chews are the bulkiest to carry. The package is large, but as a bonus, it does pack two servings rather than one.

They are definitely hard to chew on the go. I think the chews are best suited for pre-run or mid-interval workout when you have a second to chew thoroughly. These are super delicious though. Who doesn’t love gummies? My go-to's are the strawberry ones.


Finally, the stroopwafels are very thin but will break in the package if you are too rough with them. They did fit in a pocket on one of my run leggings, and the breakage didn’t bother me since I was going to eat it anyways! They are definitely the most difficult to eat on the fly as they’re the dryest- be sure to have water at hand.

I find the stroopwafels shine as a pre-run snack.

I’ve been enjoying a coffee with a stroopwafel before my training sessions recently and I love having my little coffee and stroopwafel moment. It rates super high in deliciousness as a result. My absolute favourite is the campfire smores one.


Don’t make your run harder than it needs to be

Next time you head out for a run, try fuelling with a GU product.

Since I learned proper fueling techniques when I became a collegiate runner, I have experienced far less digestive distress and have finished training sessions and races with far less fatigue and feeling much stronger.

The most important thing to remember is everyone has their own “secret recipe” for fuel. Don’t be afraid to experiment to find what makes you feel your best.


An R&R staff member and lifelong runner, Cayla is passionate about helping all runners think like top-level athletes.

Related Articles