Getting Ready: What to Eat Before a Run?

For many, running is not just a workout; it’s a passion and a lifestyle. You have been putting in the work, building up your endurance and routine, and now have decided it is time for the big challenge — the long run. Maybe you are even working up to your first half-marathon. Or perhaps you already have some long runs under your belt but felt like you hit a wall during them, felt fatigued, or even had digestive issues.

In either case, the question is, what should you eat before a run? Properly fuelling your training can significantly impact your performance and recovery.

In this article, I explore what to eat before a run, providing examples of pre-run meals and different approaches based on the time available before your session. I also explain the importance of nutrition in sustaining energy and reducing digestive discomfort.

Why is thinking about food before a run important?

Investing in good shoes, clothes, and other gear is essential to making your run more comfortable and enjoyable. However, focusing on nutrition is key to ensuring you have the fuel to perform and recover. Without proper nutrition before your run, you may find your energy levels tanking too soon or feeling overly hungry, or the opposite, where you feel sluggish and heavy. Undereating, overeating, or simply hitting the wrong macronutrient balance can make or break your run.

Even if you are used to running on an empty stomach for short runs, I strongly suggest against it for runs over 60 minutes — more extended periods of high-intensity exercise, such as running, strain energy stores, and fluid regulation. The body relies on glycogen stores in the muscle to fuel the workout. Glycogen stores are like a bank account where carbohydrates are stored to fuel activity when needed. Thus, eating adequate amounts of carbohydrates before the run is required to ensure the stores are full to the brim and give you instant energy so you have fuel before tapping into the saved stores.

You should not go out running on a full stomach, but eating something before a morning run will likely leave you feeling better and may even allow you to push yourself harder. Of course, the running police will not come for you if you choose to run fasted, but your long run may end up being shorter than expected, as starting prolonged exercise on low glycogen stores may reduce workout capacity.

What kind of foods should I focus on?

The general recommendation is 1–4 grams of carbohydrates per kg of body weight 1–4 hours before exercise. The more time you have until your run, the more you can eat. As filling up your glycogen stores and fuelling your run is the primary goal, your pre-run meal should comprise simple carbs, like whole-grain toast, rice cakes, fruits, white rice pasta, and similar. You should also have some protein to keep you full during your run but limit your fats — yes, including healthy fats — as they may slow down digestion and make you feel sluggish.

There is no single best pre-run meal or snack, as it depends on your metrics, running intensity and distance, your nutrition in the previous days, and so on. Most studies have been done on athletes, mostly male marathon or half-marathon runners. These people are usually chasing goals and aim to optimize their nutrition, but if you are more of a recreational athlete, you may not need to track your carbohydrates by the gram and just focus on eating more before your long run.

If you consume caffeine, you may also want to drink 3–6 mg of caffeine per kg of body weight 30–90 minutes before your run for maximum benefits. However, remember that the FDA recommends not exceeding 400 mg of caffeine daily.

In summary, you should focus on:

Foods to consider avoiding

I avoid labeling foods as bad to eat as it screams diet culture, but when it comes to long runs or other intense exercise, there are some ‘wrong foods’ you may want to avoid for a smoother experience. Most of these are part of a healthy diet, but the goal is exercise performance right now, which requires a different approach.

• High-fat foods. Fats slow digestion, which can result in food not being fully digested before your run, leaving you feeling heavy and full. These include bacon, cheese, a large amount of nut butter, fried foods, creamy sauces, and similar.
• High-fiber foods. Fiber can increase gut motility and clearance, which is essential for gut health but not great for a run. High-fiber foods like cruciferous vegetables, whole grains, legumes, or large quantities of any plant-based food before your run can leave you feeling bloated, gassy, and needing to go to the bathroom mid-run.
• Spicy food. Spice can irritate your gastrointestinal tract and may even cause diarrhea when combined with running. So, no hot sauce on your eggs before the run.
• Carbonated drinks. Bubbles are gas, equal to bloating and even burping, especially when combined with running. So opt for still water and refrain from energy drinks.
• Large meals before the run. Avoid large meals 3–4 hours before your run so your body has enough time to digest and feel light rather than full and sluggish.

When should I eat before my run?

When you should eat before running depends on whether you run in the morning or afternoon and how much time you have.

If you prefer a morning run, aim to have a light pre-run snack of easily digestible carbs at least 30 minutes before your run and focus on higher carb intake the day before.

If you run later in the day, you should focus on more digestible meals and carbs throughout the day. Eat your last big pre-run meal 3–4 hours beforehand, and have a pre-run snack later if needed.

Here are some of the best foods to eat before running:

Fueling for longer: what about prolonged runs?

The term ‘long run’ is a bit vague, and it is better to focus on the distance and intensity of the workout, as these factors impact nutrition more. Most of the studies on nutrition for runners focus on half or full marathons or ultra-long distances, and participants are usually elite athletes or well-trained individuals. Another caveat is that most studies have been done on males. Yet, females may require slightly different approaches due to their hormone fluctuations, different metabolisms, overall muscle mass, and other factors.

I asked registered dietitian and avid runner Jennie Waegelein for some insights. She says that whether a run requires special nutrition depends not only on the duration of the run but also on personal goals. “If you are planning on running more than 90 minutes, or running a half or full marathon, a carb load starting a few days (3–5) out from the race, with increased electrolytes + hydration, is super important! However, if you are hoping to compete or hit a personal record in a shorter race, like a 5k, I would say it is equally important to increase carb intake + hydration with electrolytes 1–2 days before the race to optimize glycogen stores. Otherwise, for shorter races, eat some easy-to-digest carbs ahead of your run, but don't stress too much about changing your nutrition — just go out and enjoy yourself!”

Many marathon runners and other endurance athletes use carb loading. It involves increasing carbohydrate intake one or several days before your long run.

If you are running a longer race, like a marathon, carb loading a few days out will be essential to allow your body to hold on to the necessary glycogen stores needed to maintain muscle energy and integrity throughout the race. These carbs, along with those you consume during the run, will be what allow you to finish strong and avoid ‘bonking’ mid-race, as many runners experience. Again, carbs are important, but hydration (with electrolytes!) are equally as important.

Jennie Waegelein

This does not need to be overly complicated. She says you can just “include a higher carb snack or two or increasing portion sizes of your carbs at meals to take the ‘stress’ out of it.”

Specific amounts depend on your body weight, running intensity, overall diet, and preferences. When asked, a registered dietitian, Liz Wyosnick, advised timing “a bigger meal 2 hours before the run, and then a small carbohydrate snack 20 minutes before the run. This meal plus a ‘top-off’ snack should last someone for 60–75 minutes of running. If you plan to run more than 75 minutes, you may need some ‘during fuel,’ such as a sports drink or energy gel.”

Focus on nutrition, with a bit more carbs a few days before your run to have sustainable energy. Eat well on race day, have easily digestible carbs for a quick energy boost, and hydrate before and during the run, not just after.

Listening to your body: what works best for you

Despite the science, different foods can affect each person differently. One may thrive off having whole-wheat toast with jam as their pre-run snack, while another may swear by oats and a banana as their pre-race meal. The general rule is to focus on easily digestible foods, carbohydrates, some protein, and hydration. Do not try new foods or combinations as your pre-run meal, and save foods high in fats, fiber, and protein for your recovery.

Final thoughts

Despite numerous available guidelines, fuelling for a run is not a one-size-fits-all. You should focus on balanced meals with more carbs several days before your run, hydration, and easily digestible carbs as a pre-run snack. Ultimately, the best meal or approach will differ from person to person.

You should not do a long run on an empty stomach, and even if you did not adjust your nutrition on the days before the race, eating a pre-run snack could still improve your performance and recovery. For best results, you should consult a registered dietitian or sports nutritionist for a personalized approach. If that is unavailable, try a few tactics and find what works best for you and leaves you with sustained energy levels.