What should you eat before endurance exercise?

Jan 12

If you’ve ever opened the fridge door, pondering what to eat before your workout, you’re not alone. Sports scientists, exercise physiologists, and nutritionists have debated this for decades. And while significant progress has been made in our understanding of nutrition, the body, and exercise, there is no still no one-size-fits all answer.

Pre-exercise nutrition has the ability to alter our metabolism during exercise, stimulate training adaptations, and enhance performance.

For example, eating higher fat foods before exercise will increase fat oxidation (burning) during exercise and may help to “save” muscle glycogen, additional energy reserves for later in the session. On the other hand, carbohydrate-rich meals or drink before endurance exercise will increase body’s carbohydrate use and suppress fat oxidation.

Some athletes choose not to eat before morning exercise (i.e. fasted training). This is based on the belief that this type of training will enhance their ability to “burn” fat and reduce any gut discomfort. However, other athletes find this trade-off does not work for them, as the quality of their sessions suffer as a result.

What we do know from research and from athlete experience, is the importance of the following factors, which could help to decide what to eat and drink before heading out:

Exercise intensity (e.g. low, moderate, and high)
Exercise duration
Personal tastes and preferences.

LOW-INTENSITY

(COMFORTABLE, CONVERSATIONAL: FEELS LIKE 1-4 OUT OF 10)

Low-intensity exercise doesn’t always require high carbohydrate availability, as we can tap into our fat stores to supply energy for working muscles. Therefore, a meal or snack a few hours before exercise that has higher protein and fat content can work well. This way your body will favour fat-burning, while preserving muscle glycogen for later stages of exercise.

Some examples of higher protein and fat pre-exercise foods:

Roam ENB (nut butter) with a piece of fruit.
Eggs with avocado.
Protein shake or protein smoothie with nut butter blended in.

MODERATE-INTENSITY

(SUSTAINED EFFORT: FEELS LIKE 5-7 OUT OF 10)

During moderate-intensity exercise your body will start favouring carb-based fuels while still maintaining reasonable fat burning. It is very individual what ratio of fat or carbs we burn in this intensity zone, something that also depends on your level of fitness, your overall diet and other factors. The most important preparation for moderate-intensity sessions actually happens the day prior, by eating meals that supply all macronutrients and top-up energy stores for the following day’s session. Thus immediate pre-workout choices will depend on your goals. If your focus is solely performance — a carbohydrate-rich breakfast/snack will provide immediate energy for the session. If you are after metabolic benefits— a protein/fat-rich meal or snack is also a great option.

HIGH-INTENSITY

(CHALLENGING: FEELS LIKE 8 OUT OF 10)

These sessions will be demanding on your body, and you should consider consuming carbohydrate-rich meals beforehand to replenish muscle glycogen (this is how your body stores the majority of carbohydrates in your body). Ideally, you will start thinking about “restocking” muscle glycogen at least 24 hours before the session, as it takes time to pack your muscles with energy, it is not a fast process. However, eating carbs 4-6 hours before your workout will top off muscle and liver glycogen stores. Meals (breakfast, lunch) before these workouts are important, don’t skip them! If you are confident that your body has plenty of energy stored earlier in that case you can even enjoy a snack either rich in carbohydrates or protein/fat, usually 1-2 hours before the session.

Some examples:
Breakfast: oats with berries and Roam
Pre-workout: half-banana, energy bar, Roam

WHAT IF I’M RAVENOUS HALF AN HOUR BEFORE MY WORKOUT, BUT DON’T WANT TO EXERCISE ON A FULL STOMACH?

Sometimes we just need something to ‘fill the gap’ before training. A full meal will be too heavy and could compromise your workout, and foods like bread and crackers don’t always sit well.

In this situation, foods that are easy on the stomach and small are good:

Half a banana
A packet of Roam (ground nuts will be easier for your gut to handle than whole nuts)
Half a protein shake.

EXERCISE DURATION

Long workouts or races don’t necessarily mean that you need to increase the volume of what you eat pre-exercise. Over-eating can make you feel heavy and sluggish and can adversely affect your performance and overall experience. For sessions over 1.5 hours in length, you will likely need to consider bringing energy with you.

Andrius Ramonas