Caffeine, glorious caffeine.
Known for its mind and body stimulating effects, caffeine is the most widely consumed drug globally.
You might even be caffeinated as you read this.
Caffeine is found in many plants' leaves, seeds, and fruits, including tea leaves, cocoa beans, and coffee beans.
Over 90% of adults in the U.S consume caffeine EVERY DAY. That’s one hell of a statistic.
But what does the science say about caffeine, is it really beneficial for physical performance? Mental focus? As a fat burner?
Grab yourself a brew, and let’s get into it.
How it works - caffeine exerts its effects by blocking adenosine receptors in the brain from binding. Think of adenosine as an “I’m sleepy and relaxed” signal that accumulates over the course of a day.
Caffeine blocks this effect, thus producing the stimulating effects we know and love.
Physical performance: The International Society of Sports Nutrition found caffeine to acutely enhance various aspects of physical performance including muscular endurance, muscular strength, and movement velocity in addition to sprinting, jumping and throwing performance.
Mental performance: Another study concluded that caffeine improved alertness, vigilance, attention, reaction time and attention, along with some less consistent effects on higher cognitive functions like judgement and decision making.
Fat burning: A meta-analysis published in 2020 demonstrated that caffeine significantly increased fat oxidation during exercise, which would scale dose-dependently. This increase in fat oxidation was also glucose preserving, thus increasing performance.
All that said, how much caffeine should you consume for optimal results?
The recommended dose varies by body weight, but it’s typically about 200–400 mg, taken 30–60 minutes before a workout.
One cup of coffee typically contains around 95mg of caffeine, while an energy drink like Monster Zero contains 150mg.
While we’ve discussed the benefits of caffeine, be aware that it can lower your sleep quality if consumed too close to bedtime. My recommendation would be to cut it out after 2 pm, but caffeine processing and sensitivity vary by individual. See what works best for your body and schedule.
References
Collado-Mateo, D., Lavín-Pérez, A., Merellano-Navarro, E. and Coso, J., 2020. Effect of Acute Caffeine Intake on the Fat Oxidation Rate during Exercise: A Systematic Review and Meta-Analysis. Nutrients, 12(12), p.3603.
Guest, N., VanDusseldorp, T., Nelson, M., Grgic, J., Schoenfeld, B., Jenkins, N., Arent, S., Antonio, J., Stout, J., Trexler, E., Smith-Ryan, A., Goldstein, E., Kalman, D. and Campbell, B., 2021. International society of sports nutrition position stand: caffeine and exercise performance. Journal of the International Society of Sports Nutrition, 18(1).
McLellan, T., Caldwell, J. and Lieberman, H., 2016. A review of caffeine’s effects on cognitive, physical and occupational performance. Neuroscience & Biobehavioral Reviews, 71, pp.294-312.