Fueling Your Workouts: What to Eat Before Exercising
This post will guide you on what and when to eat before a workout.
The double-edged sword of fueling your workouts
Exercise requires energy, and by “energy”, I mean “food”. Although, the foods you choose and when you eat them can impact your workout in many ways.
Having 3 eggs with spinach and a large bowl of oatmeal with peanut butter and banana might be a great way to fuel a hard workout in 2-4 hours. However, this is a bad idea if you plan on exercising 20 minutes later.
Fueling your workouts is a fine line of getting enough energy and avoiding stomach issues, and some of us have stronger stomachs than others.
Fueling your workout >4 hours away
This study examined the effect of skipping breakfast on evening exercise performance.
Subjects were either given a breakfast or instructed to skip breakfast. Both groups were allowed to eat as much as they would like for both lunch and dinner.
The timeline was as follows:
Breakfast or no breakfast
4.5 hours later, lunch. Both groups at as much as they wanted.
9 hours after breakfast, both groups performed a 30-minute maximal cycling test after a 30-minute sub-maximal warm up.
11 hours after breakfast, dinner. Both groups at as much as they wanted.
The results showed that the group that ate breakfast outperformed the group that skipped breakfast. Even with the exercise test being 9 hours after breakfast, and both groups being allowed to eat as much as they pleased at lunch, eating a breakfast had a significant impact on the outcomes of the exercise test.
Fueling your workout within 2 hours
This study examined how eating before a workout impacts exercise performance.
Both groups in this study ate the same breakfast and lunch, and they were free to eat as much as they wanted after the evening workout.
The only difference between the groups was that the “fasting” group skipped dinner, while the “fed” group did not. The fasting group had their last meal 7 hours before the exercise bout, while the fed group had their last meal 2 hours before.
The authors spoil the results in the title. The fed group outperformed the fasting group by 3.8% in total work during the exercise test.
While 3.8% might seem small, it is not when brought into context. 3.8% is the difference between lifting 200 pounds or 207 pounds and running 10:00-minutes per mile instead of 9:46-minutes per mile.
Further, the researchers looked at the psychological impact of skipping the pre-exercise meal and found that the “fasting” group had lower subjective ratings of motivation, readiness, energy, and overall exercise enjoyment.
I would argue that these psychological findings are the most important of the whole study.
An important highlight of both studies
Both studies tracked total caloric intake across the whole day. Even though the meal-skipping groups were allowed to eat as much as they wanted during their allotted mealtimes, they ate fewer calories across the whole day.
As it was stated in the first sentence of this article, “Exercise requires energy”, and we get our energy from calories. More calories = more energy to put towards exercise. *****
Composition of your pre-workout meal
While the International Society of Sports Nutrition studies athletes, I find that their work can apply to the average exerciser. Their article on nutrient timing looked at “what” to eat and “when” to eat to maximize exercise performance.
This position stand is lengthy, but there is a general trend. It seems to be beneficial to have a meal high in carbohydrates before exercise, as well as some protein (20-40 grams is recommended in this article).
The amount of carbohydrates you should have before exercise is dependent on the intensity and duration of exercise, whether you plan on having carbohydrates during exercise (like a sports drink), and time until exercise.
Summary
There is strong evidence to suggest that eating before you exercise will improve performance, whether that meal is 1 or 8+ hours away from your workout. Also, the evidence suggests that most of that meal should be composed of carbohydrates along with some protein.
With all of this in mind, it is important to note that, unless you are a professional athlete, you can’t only focus on your physical performance. What might be good for exercise performance might be detrimental to your health.
For example: Drinking 2 cans of coke 20 minutes before a hard strength training session would probably help your performance, but I certainly wouldn’t call it healthy.
Here are some general rules to follow:
When eating 2-3+ hours away from your workout, your meal should look like a standard, well-rounded meal. It should include a source of protein, carbs, fat, and fiber.
When eating closer to your workout, fat and fiber intake should be decreased. This is because you risk having GI distress when having these foods before exercise.
Carbohydrates should increase when doing longer or harder workouts.
Examples of what I would eat leading into a workout
3-4+ hours away: Any meal with plenty of fiber, protein, carbs, and fat.
1.5-2 hours away: Oatmeal with peanut butter and fruit, pasta with a small amount of vegetables, protein pancakes, or a fruit smoothie with some protein powder in it.
15-60 minutes away: Peanut butter and jelly sandwich, a banana (or 2), or cereal that’s meant for children (my current go-to is Cinnamon Toast Crunch).
These are examples of what I would have, and it might work for everyone. But it highlights the priority of fueling my workouts properly while minimizing the risk of wrecking my stomach.
Weight loss and exercise performance
Since there is a strong correlation between energy availability (calories) and exercise performance, it can be difficult to properly fuel your workouts when trying to lose weight. And that’s okay!
Exercise is a stress on the body, and so is weight loss. It is completely reasonable for exercise performance to be suboptimal while you prioritize achieving your weight loss goals.