Caffeine is a substance that improves performance and is used by many athletes, both in everyday life and during competitions. The positive effect of caffeine on performance has been known for over 100 years. Indeed, the first study on the effect of caffeine on participants was published in 1907.
Over the years, studies have shown positive effects on:
- Maximum strength
- Isokinetic force (movement assisted by a machine at constant speed)
- Vertical jump height
- The power developed through different sports (cycling, rowing, etc.)
- Muscular endurance
- Aerobic performance
Caffeine also reduces the feeling of fatigue and the perception of effort during physical exertion. A meta-analysis showed that caffeine ingestion reduces the perception of exertion by six per cent during physical exertion.
Caffeine also has a positive effect on cognitive performance, even more so in a state of sleep deprivation.
It has also been observed that ingesting caffeine before strength training would reduce the effect of pain and soreness following training, but more studies are needed to confirm this effect. Also it has been shown that the ingestion of caffeine, especially coffee (due to the presence also ofothermolecules such as caffeic acid and cafestol) following physical exertion, can improve the replenishment of glycogen in the muscles.
The placebo effect of caffeine (and any supplement)
We must also not forget that the simple fact of knowing that we are ingesting a substance that is supposed to have a positive effect has a placebo effect that allows us to perform better (placebo is a positive effect caused by the simple fact of believing that we have consumed something that is supposed to improve performance). For example, one study investigated the placebo effect of caffeine. The researchers told the participants that they would consume a control solution in one of the experiments, and a solution with caffeine in the other experiment. On the other hand, in fact, in both cases they had a caffeine-free control solution. When they thought they had ingested caffeine there was an increase in their performance on a muscle endurance test and their perception of exertion decreased. This placebo effect of caffeine has also been demonstrated in bicycle tests.
How much caffeine?
It is recommended to consume 3 to 6 mg of caffeine per kg of body weight 60 minutes before physical exertion. For a 75 kg (165 pound) athlete, this represents 225 to 450 mg of caffeine, which is a very high amount of caffeine. In comparison, the average amount of caffeine consumed by Americans is 165 mg per day.
Why do some people need more caffeine to feel an effect?
There is a lot of inter-individual variation, that is, some people react much more than others to a certain amount of caffeine, so they need less caffeine. This can be explained, among other things, by genetic variations. Also, there seems to be an addictive effect, so over the years if you drink a lot of coffee, it is quite possible that you will have to drink more coffee to feel the same effect as when you first drank coffee. It is for this reason that some athletes decide to stop drinking caffeine the week before a race to have an even more significant positive effect on the morning of the race. On the other hand, this period of caffeine withdrawal before the competition can be associated with negative effects, such as fatigue and irritability. Another way to increase the effect of caffeine on the day of the competition is to increase the amount of caffeine consumed compared to the amount usually consumed. For example, if you usually consume 2 to 3 mg of caffeine per kg of body weight, on the morning of the competition you could increase the amount to 4 to 5 mg/kg. Obviously, it’s important to test it a few times before training!
Potentially negative effects of caffeine
Although caffeine has several positive effects, it is still important to mention some potentially negative effects.
- Caffeine can increase feelings of anxiety
This can be problematic especially before a big competition when the level of anxiety is already very high.
- Caffeine ingestion, especially in the afternoon, can impair sleep quality and thus impairrecovery.
For example, ingesting 400 mg of caffeine 6 hours before sleep time has been shown to increase the time before the person falls asleep and decrease the duration and quality of sleep.
The day before a competition, or even an important workout, try not to consume caffeine in the afternoon since the shelf life of caffeine in the system is long and, so even if you have a coffee around 2pm, it could still affect your sleep.
A coffee, an energy drink or in the form of gum?
The majority of people ingest their caffeine in the form of coffee. On the other hand, the amount of caffeine can vary significantly depending on the brand of coffee, the type of bean and the duration of infusion. So, if you want to consume a specific amount of caffeine before your competition, it may be better to find another option. Also, coffee can be an irritant to the stomach, especially before an intense effort.
Caffeine-containing gums are a good option and they allow for faster caffeine absorption than a caffeine pill. However, the long-term effect is the same. Energy drinks can be another option, but you must be careful since the majority also contain other ingredients like taurine and gurarana, and the majority contain a lot of added sugar.
During competition, it is possible to ingest caffeine in the form of gels or jujubes (personally I eat Clif shots containing caffeine), or in liquid form (I sometimes use the TailWind drink which contains electrolytes and caffeine).
In short, caffeine is a supplement that can significantly help you perform better. On the other hand, it is necessary to make sure to take enough to have positive effects without taking too much and risking having negative effects (palpitations, high level of anxiety etc.). Also, it is important to think about when we ingest caffeine so that our caffeine consumption does not affect our sleep or recovery.