Should I eat? If so, what? And when? Not to mention that the “what” depends on the “when.” Knowing what to eat before an activity raises several questions, but don’t worry, it’s simpler than it seems!
In brief
- 3 to 4 hours before: a normal meal, moderate in fat.
- 1 to 2 hours before: a snack mostly rich in carbohydrates, with a little protein.
- Less than 1 hour before: a small snack rich in carbohydrates and easy to digest.
- Training on an empty stomach is possible for a short, moderate session, but not for intense effort or activity lasting more than an hour.
- Before an event lasting more than 90 minutes: increase carbohydrate intake for 1 to 2 days.
Can I train on an empty stomach?
You can… if your body wants to.
Many athletes are able to train without breakfast, but it’s largely a matter of experience. It’s not recommended for less experienced athletes, as they might feel weak, see stars, or experience another similar type of discomfort. If it’s something you’d like to do, gradually get your body used to it by starting with short sessions at moderate intensity. Always keep a bar, an energy ball, or a sports drink on hand, just in case.
In any case, training on an empty stomach isn’t advisable if the activity is intense or lasts more than an hour.
How should I plan my pre-workout snack or meal?
When you work out, you want to have energy and feel light. If your activity takes place around lunchtime or at the end of the day, your previous meal may be enough. If you feel hungry in the meantime, that’s a sign you should eat a snack. Here’s a guide to choosing suitable foods:
| Time before the activity | What to eat | Examples |
|---|---|---|
| 3 to 4 hours | Normal meal, ideally moderate in fat (no fried foods) | Chicken stir-fry and rice, tuna pasta, sandwich and raw vegetables |
| 1 to 2 hours | Snack or very light meal, mainly carbohydrates and a little protein | Bread, muffin, Zenit energy square, yogurt, hummus |
| Less than 1 hour | Light snack rich in carbohydrates and easy to digest | Zenit energy balls, dried fruit, banana |
For those who are more curious: it’s generally recommended to consume 1 to 4 g of carbohydrates per kg of body weight in the 1 to 4 hours before strenuous exercise. The shorter the time, the smaller the portion.
How do I prepare for a BIG workout?
The goal is to maximize energy stores so you can perform at your best. Here’s what you can do during the 1 to 2 days before the event or mega-workout, especially if it lasts more than 90 minutes:
- Eat meals rich in carbohydrates, with pasta, bread, rice, potatoes, etc. making up about half the plate. (To learn more, read our article on carbohydrate loading.)
- Choose carbohydrate-rich snacks when you’re hungry: Zenit energy squares or balls, muffins, banana bread, fresh or dried fruit, yogurt, smoothies, etc.
- Drink enough water. It’s important to be well hydrated to store energy in your muscles and to keep your cooling system (sweating!) working optimally.
- Avoid alcohol: it has a dehydrating effect and interferes with energy storage.
IMPORTANT: each of us tolerates foods differently. Sometimes we need to use trial and error to find out what works best for us. Try these foods during your training sessions and avoid doing so before an important event or competition. In these situations, stick with what you know you tolerate. It would be a shame to have a stomachache ruin the outing…
Frequently asked questions
How long before exercising should I eat?
Ideally, have a meal 3 to 4 hours beforehand, or a light snack 1 to 2 hours beforehand. Less than an hour before, choose a small snack rich in carbohydrates and easy to digest.
What should I eat 30 minutes before running?
A small snack rich in carbohydrates and low in fat and fiber: a banana, dried fruit, or an energy ball.
Is it bad to train on an empty stomach?
No, for a short, moderate session if you’re used to it. It’s not recommended for intense effort or activity lasting more than an hour.
How can I fuel up before a race?
During the 1 to 2 days before an event lasting more than 90 minutes, increase your carbohydrate intake at every meal and snack, drink enough fluids, and avoid alcohol.
By Stéphanie Côté, M.Sc., nutritionist
Speaker and author of “Knowing What to Eat – Sports Nutrition,” published by Modus Vivendi, 2019
Reviewed and updated in October 2026 by Danielle Dubois, nutritionist.
References
- Thomas DT, Erdman KA, Burke LM. Position of the Academy of Nutrition and Dietetics, Dietitians of Canada, and the American College of Sports Medicine: Nutrition and Athletic Performance. Med Sci Sports Exerc. 2016;48(3):543-568. PMID: 26891166
- Kerksick CM, Arent S, Schoenfeld BJ, et al. International society of sports nutrition position stand: nutrient timing. J Int Soc Sports Nutr. 2017;14:33. PMC5596471