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The fact that appropriate amounts of caffeine can increase both performance and motivation when it comes to sport is widely acknowledged in sports science. The question, however, is: how exactly should we use caffeine? Here are some key questions and answers about caffeine.

How does caffeine affect the body?

Caffeine is a stimulant and increases alertness and concentration. It primarily affects the central nervous system. The caffeine molecules “infiltrate” the adenosine receptors to reduce feelings of tiredness. Other effects include an increase in adrenaline and noradrenaline along with a greater distribution of calcium around the muscle cells. This enhances the ability of the muscles to contract. It also reduces our subjective sense of exertion and pain while doing sport. This offers additional positive benefits for athletes, particularly where physical, mental and muscular fatigue is already at an elevated level, for example at the end of a long, endurance workout.

Does caffeine increase fat metabolism?

Caffeine can slightly increase the release of fatty acids from the fat tissue and, under specific laboratory situations, fat burning. However, studies have also shown that caffeine does not have a relevant impact on fat burning during sport. Athletes don’t burn more fat by consuming caffeine.

What is the perfect dosage?

The dosage and effects of caffeine vary from person to person. The ideal recommended dosage is 3 to 6 mg per kg of body weight. This corresponds to around two or three espressos, three cups of filter coffee, two cans of Red Bull or one caffeine tablet.

Even lower doses (1 to 3 mg per kg of body weight) can have positive effects during sport. Higher doses, on the other hand, can produce negative effects and even result in a reduction in performance.

The maximum concentration in the blood plasma is reached around 30 to 60 minutes after consumption. After this point, the greatest or largest positive effects can be seen. The timing may vary slightly depending on how the caffeine is administered. The half-life of caffeine is 5 hours and the positive effects begin to wear off over time, meaning more caffeine must then be consumed to maintain the desired effect.

How much caffeine is found in what?

• Coffee 150 ml = 80-150 mg depending on how the coffee is brewed
• Espresso 30 ml = 30-80 mg
• 1 cup of black tea = 20-40 mg
• Milk chocolate 100 g = 15 mg
• Coca Cola 250 ml = 25 mg
• Can of Red Bull 250 ml = 80 mg
• Caffeinated gel = 25 to 100 mg depending on portion size
• Caffeine tablet = between 50 and 200 mg depending on the supplier
• Caffeine booster = 160 to 200 mg depending on the supplier

What are the disadvantages of caffeine?

Possible side effects - particularly for people who do not regularly consume caffeine - include insomnia, heart palpitations, trembling, headaches, feelings of panic and an irregular pulse. For evening competitions, it may negatively impact quality of sleep and recovery. Since half of the maximum caffeine quantity remains in the bloodstream after 5 hours, those who are more sensitive to caffeine may experience issues falling and staying asleep, resulting in a poorer quality of sleep.

Is caffeine more effective after a withdrawal?

For many endurance athletes, stopping caffeine consumption before a competition is a popular and subjectively effective strategy for increasing its impact. However, study results are unclear as to whether caffeine does in fact have a greater impact after a period of withdrawal, or whether this is just a perceived benefit. A far more decisive factor seems to be if someone is a responder or non-responder.

Also, the potential side effects of caffeine withdrawal must be taken into consideration. Some people can experience severe withdrawal symptoms such as strong headaches, which speaks against drastic caffeine reduction. Athletes with a very high daily caffeine intake can try reducing their consumption before a major competition.