Home > Trail Running

Fuelling for a trail race: solid versus liquid calories

Learn how trail runners train their tummy for the long run

To each their own seems to be the broad rule that defines trail running nutrition. The longer we go in trail running, the more opportunities we have to experiment with the right mix of calories for the long run. One size fits one for most trail runners, and it can be a game of experimentation as we train our tummies, figuring out what works. These days, the plethora of fuelling options can be overwhelming, especially when some of it does not even resemble real food. More options on the market can mean more confusion. Holistic nutritionist, mountaineer, 50K and 100K treadmill world record holder, and national level OCR racer Arielle Fitzgerald shares her thoughts on solid versus liquid calories.

RELATED: How to fuel for a 50K trail race

Photo: Instagram

Solid calories

Solid fuelling options range from gels to dates to burritos and sandwiches on the trail. Most gels we are familiar with are simple carbohydrates with added electrolytes. Other solid calorie choices, however, don’t necessarily take into account your electrolyte needs. Although there is more variety for fuelling when choosing solid food, and foods like avocado can satiate you longer, they don’t necessarily provide you with what you need in harder efforts.

Fitzgerald recommends solid food for longer and slower days. She explains, “the slower you’re moving, the slower you want your food to move through you. Solid food usually maintains blood sugar levels at lower intensities. As the duration of a race increases, you don’t want to be dependent on sugar, as it can upset your stomach. A long race could result in more frequent ‘bonks’ (as well as digestive distress) with too much sugar in our system. Solid food is often better for lower intensity, as it can allow you to be in more of a fat burning state.”

Liquid calories

Liquid calories for running are usually products that dissolve in water. They are more than your average electrolyte tab, and include carbohydrate, electrolyte, and some protein calories that are fast absorbing. Fitzgerald says that when running at higher intensities, we need a higher concentration of carbohydrates that our bodies can use quickly. “Liquid calories can be easier on the stomach. Ideally, we don’t want to be entirely dependent on simple sugars for longer endurance races.”

RELATED: RECIPE: Chocolate trail truffles

Photo: Tory Scholz

All the calories

Many athletes are moving toward relying on both solid and liquid calories for their trail and ultrarunning races (think Tailwind in conjunction with gels or whatever your heart desires). Fitzgerald recommends that your calorie source depend on the type of terrain you’re running. For example, if you’re running a 100K mountain race, then your body requires food that can maintain blood sugars for longer (think nut butters or avocado). If you are racing a shorter trail race at a higher intensity, you may be able to get by with just liquid calories. Choosing both solid and liquid calories may mean you are going at a high intensity for a longer trail ultrarunning event (like racing for a Golden Ticket). Like most things in life, choosing solid versus liquid calories depends on the individual event as well as the individual runner.

RELATED: How to run a stage race