Caffeine is the most well-known tonic substance used in supplements and stimulant drinks.

How does he act?
The first effects of intake of caffeine are felt after 15 minutes, being eliminated slowly (thinking about individual variables) maintains its effect for several hours after intake.

The probable factors related to the improvement of the performance are three:
- l effect on tiredness and fatigue
- the mobilization of fats, thus an additional long-term energy source
- l’increase in the absorption of sugars in the small intestine

But with the heat?
Studies done on trained runners show how the heat and especially the humidity hide the ergogenic effect of caffeine during the activity.
Also In addition, if the athlete is dehydrated, there is a risk of cramping.
So caffeine yes, but very moderately on hot-humid days.

Dott.ssa Annalisa Faè