Caffeine has been widely studied and used around the world, particularly in sports. Many athletes turn to caffeine, whether in their morning cup of coffee or in the form of energy supplements, to boost their performance. But what are the true effects of caffeine, and how can it be incorporated safely and effectively?
The effects of caffeine on your body:
Caffeine acts as a stimulant for the central nervous system, which can:
- Reduce the sensation of fatigue
- Improve alertness and concentration
- Stimulate the release of endorphins, the feel-good neurotransmitters, providing a mental and emotional boost during exercise.
Benefits of caffeine for endurance:
- Improved performance: it can increase endurance, delay fatigue, and improve concentration.
- Reduced perception of effort: it makes intense exercise more tolerable.
When and how to consume caffeine for sports?
Before exercise: It is recommended to take a dose of 3 to 6 mg of caffeine per kilogram of body weight. For example, for a 56 kg athlete, this equals 170 to 335 mg of caffeine. This dose should be consumed 60 minutes before exercise to maximize its effects.
During exercise: For prolonged efforts (more than one hour), doses of 1 to 3 mg of caffeine per kilogram can be effective. Caffeine can be consumed in the form of capsules, gels, drinks, or energy squares to maintain energy and concentration.
Pre-workouts: be cautious!
It is important to be careful with “pre-workout” blends, which are very popular, as their caffeine content varies between 50 and 300 mg per serving. It is also essential to check the other ingredients and make sure the product is Informed Sport certified to avoid ending up with banned substances in your body. And yes, there are unreliable products!
Sources of caffeine:
Caffeine is naturally found in coffee, tea, dark chocolate, certain sports supplements, and caffeine capsules available at pharmacies. Be sure to choose reliable and safe sources.

A caffeine boost from Zenit
The Zenit chocolate and coffee energy square contains 10 coffee beans with a high caffeine content. It provides the equivalent of a small espresso — perfect for helping you perform while enjoying a delicious treat!
In conclusion, caffeine can be a valuable ally for improving your athletic performance, but it is essential to test it during your training sessions to adjust the dose according to your individual tolerance.
For personalized advice, do not hesitate to consult a sports nutritionist.
References: Bas, Fatih. What are the roles of caffeine and creatine in improving athletic performance?. Faculty of Pharmacy and Biomedical Sciences, Université catholique de Louvain, 2020. Prom.: Thissen, Jean-Paul.
Bagchi, D. (Ed.). (2017). Sustained Energy for Enhanced Human Functions and Activity. Academic press.
Burke, L. M. (2008). Caffeine and sports performance. Applied physiology, nutrition, and metabolism, 33(6), 1319-1334.
Guest, N. S., VanDusseldorp, T. A., Nelson, M. T., Grgic, J., Schoenfeld, B. J., Jenkins, N. D., … & Campbell, B. I. (2021). International society of sports nutrition position stand: caffeine and exercise performance. Journal of the International Society of Sports Nutrition, 18(1), 1-37.
La Vieille, S., Gillespie, Z., Bonvalot, Y., Benkhedda, K., Grinberg, N., Rotstein, J., … & Krahn, A. D. (2021). Caffeinated energy drinks in the Canadian context: health risk assessment with a focus on cardiovascular effects. Applied Physiology, Nutrition, and Metabolism, 46(9), 1019-1028.
Landolt, H. P., Dijk, D. J., Gaus, S. E., & Borbély, A. A. (1995). Caffeine reduces low-frequency delta activity in the human sleep EEG. Neuropsychopharmacology, 12(3), 229-238.
NDA, E. S. P. (2015). Scientific opinion on the safety of caffeine. Efsa Journal, 13(5), 4102.
Rotstein, J., Barber, J., Strowbridge, C., Hayward, S., Huang, R., & Godefroy, S. B. (2013). Energy drinks: an assessment of the potential health risks in the Canadian context. International Food Risk Analysis Journal, 3.
Health Canada. Caffeine: Frequently asked questions – Information for parents about caffeine in energy drinks.