Coffee, caffeine and performance

COFFEE IN THE MORNING OR EXPRESSION OF MEAL END, WE ARE ALL RESTAURED IN OUR DAILY DOSE OF COFFEE. Whether for taste or boost, its stimulating effects are appreciated by amateurs and, scientifically, they are not wrong. “Caffeine acts as a stimulant of the central nervous system and the cardiovascular system,” explains Laurent Monassier, professor of Pharmacology at the Faculty of Medicine in Strasbourg.

Its pharmacological effect occurs even at low doses, but it is already necessary to absorb a certain amount to observe an effect on performance. Caffeine is a molecule that is well known today and has no secrets for scientists. “According to clinical studies, there is an improvement in performance from 5 mg of caffeine per kilogram.

For an individual of 80 kg, it will be necessary to take 400 mg of caffeine, equivalent to three to four espressos, “continues Laurent, also a trailler of good level and author of several conferences on the doping.


Studies have shown that caffeine primarily improves performance for activities based on endurance, but also for disciplines that require attention and responsiveness (such as combat sports). “By acting on speed, caffeine increases the level of arousal, but the effect is not immediate, the development of capacities is rather over time. “In endurance sports,

Caffeine increases lactic anaerobic capacity, in other words, it maintains a very high level of intensity a little longer. But the effects do not last, the more you take regularly and the shorter the performance benefits are felt. Continuous increases in doses are needed to achieve a truly measurable effect and an effective improvement in performance.

What are the risks

For an endurance athlete, caffeine is not without consequences. Its diuretic effect is proven: consequently, you run the risk of stopping running often. “You may need to take regular breaks to meet an urgent need; On the other hand caffeine promotes dehydration, so we must be vigilant and compensate by increasing its water intake, “adds our specialist.

In addition to this first reversal of the medal, at high doses, the molecule can also promote cardiac arrhythmias and tachycardia and increase the risk of stroke (and therefore all cardiovascular problems) Of persons of a certain age, between 50 and 60 years “.

These two combined effects thus multiply the health risks and greatly temper the benefits on sports performance.


Beyond sports and endurance, caffeine can help you charge the batteries for your morning meeting. But how do you dose it so you do not turn into an electric battery? If you are a daily drinker of coffee, your power of concentration will be temporarily strengthened after having ingested 400 milligrams *.

To determine the amount of coffee, tea, or what is needed for an energy drink, divide by 400 caffeine per cup of beverage. For those mornings where you are too sleepy for this simple calculation of arithmetic, rub your eyes and refer to the table. (You can even mix and combine drinks to reach the magic number.)


Be careful to program the boost: the caffeine takes between 30 and 45 minutes to take effect, whatever its mode of setting. However, as it takes longer to no longer feel the effects – four to six hours to metabolize about half of what you have ingested – you should need less to stay alert in the afternoon.

Drink too much and you may suffer. Side effects include palpitations, tremors, upset stomach. So do not exceed 600 milligrams. No way to get nauseous in a meeting.