Caffeine, a cyclist's friend

The perfect excuse to rethink the world as a group, philosophize about life, and daydream, coffee is a very popular beverage. According to the International Coffee Organization, in 2017-2018, 162 million 60-kg bags were consumed worldwide! More than three-quarters of Canadians consider themselves heavy drinkers, with 72% consuming at least one cup per day—nearly 15% more than our American neighbors.

Although the data is difficult to quantify, I am almost certain that every seasoned cyclist recognizes coffee as an integral part of their practice. Whether drunk before or after, the secret to its success sometimes lies in unique encounters and anecdotes that forge close bonds...

Block this, activate that...

Caffeine provides experienced athletes with an advantage by giving them a feeling of lightness and absolute power. In recent years, some have even gone so far as to seek out other products that generate the same effects, in addition to providing carbohydrates, such as the famous energy drinks. Can we really expect the same results? Are we in the era of ordering an "energy latte"?

Recognized as a substance that improves athletic performance, caffeine was banned by the International Olympic Committee from 1962 to 1972. It was subsequently reinstated, then banned again by the World Anti-Doping Agency in 1986, and is now permitted under certain conditions. Since caffeine elimination varies from person to person, it is impossible to establish precise limits; therefore, a personalized monitoring program is put in place.

The popularity of caffeine lies in the ergogenic effects associated with this small molecule. Specifically, caffeine works by blocking certain receptors involved in feelings of fatigue and pain, while activating the locomotor system. In addition, it increases adrenaline secretion, which enhances the use of glucose and fatty acids in circulation (Figure 1). Finally, by inhibiting other key enzymes, it allows for better use of fatty acids during exercise (lipolysis) while conserving glycogen (Davis & Green, 2009).

Rolling on coffee

Caffeine ingested at least 3 hours before exercise may increase exercise performance. In a study conducted on amateur cyclists, it was found that a supplement of 10 mg/kg of body weight before exercise improved endurance parameters in a progressive maximal exercise test on a stationary bike. The results show that supplementation was effective, especially in athletes who did not consume much coffee. In addition to seeing their exercise time prolonged, they eliminated lactic acid more efficiently and were less breathless for the same effort compared to the placebo test (Flinn, Gregory, McNaughton, Tristram & Davies, 1990).

Another study looked at the sensation of breathlessness experienced with or without caffeine supplementation in a maximal time trial test. It also concluded that performance in athletes who took the caffeine supplement increased due to better oxygen utilization during exercise and a reduced or delayed sensation of breathlessness (Larson, 2018).

Considering certain parameters essential to good performance, other researchers observed the mood of athletes who ingested caffeine before a 20 km cycling effort. They noticed that athletes experienced more positive emotions, were more motivated, and were less mentally affected when they took a caffeine supplement (Franco-Alvarenga et al., 2019). Knowing that a bad mood can outweigh our iron legs, this is a remedy that will appeal to refined palates!

Not all equal

We all remember our first cup of filter coffee—our eyes wide, our hearts beating a little faster... The alertness it brought may have helped us finish an important assignment. As we repeated the experience regularly, we quickly realized that these effects tended to fade, leaving only a slight, continuous stimulation. For others, even after three cups, no stimulating effect is apparent. It must be said that caffeine is not metabolized in the same way in all individuals. While some people are said to be "responders," others seem to be immune.

In addition to this distinction between responders and non-responders, a certain degree of tolerance may develop if our caffeine intake is regular and relatively high. Thus, it may be that the metabolic effects are only felt at a certain dose and are less effective when we consume a lot of coffee from the outset, regardless of the dose.

Researchers wanted to compare this response to caffeine between well-trained athletes and those who exercise more recreationally. They concluded that elite athletes would benefit more from supplementation due to their higher muscle mass. The effects were more pronounced in athletes who did not consume much caffeine on a daily basis (Graham, 2001).

The downsides of energy drinks

Caffeine therefore appears to have potentially beneficial effects in those who are genetically responsive to it, who do not consume it excessively on a daily basis, and who are slightly more trained. Can the same be said of energy drinks, which sometimes claim to give endurance athletes wings?

Composed mainly of carbohydrates, energy drinks can also contain a significant amount of caffeine, ranging from 80 mg (the equivalent of an espresso) to nearly 140 mg, depending on the brand. In addition, several other ingredients may be present in varying amounts, such as taurine, natural health products, and sometimes vitamins and minerals.

The fear surrounding energy drinks is often attributed to taurine, which seems like an ingredient straight out of a laboratory. Naturally present in small quantities in meat and dairy products, taurine is actually a quasi-essential amino acid that aids in the digestion of lipids and detoxification of the liver. It is estimated that energy drinks can provide nearly 10 times the recommended amount, which can be concerning since little is known about the negative physiological effects of taurine. Furthermore, it is known that when intake is increased, the central nervous system appears to quickly become saturated and the concentration in the brain remains stable. Taurine may also help regulate several functions of the cardiorespiratory, nervous, gastrointestinal, and muscular systems (Tremblay, 2010). A recent meta-analysis looked at the effects of taurine in endurance sports and concluded that a supplement of up to 6 g per day could slightly improve endurance during sporting events (Waldron, Patterson, Tallent & Jeffries, 2018).

However, as I said, its negative effects are little known, and some authors believe that taurine could increase the harmful effects of caffeine, such as heart palpitations and tremors.

As with any product, moderate consumption is recommended, and above all, it should not be combined with alcohol.

Choose wisely

There are a few nuances to consider when choosing a food product as a sports supplement. First, it is important to understand that the positive effects on performance are attributable to the amount of caffeine present in both coffee and energy drinks. The advantage of coffee is that it is relatively inexpensive, minimally processed, and often has a social dimension that can boost motivation. Energy drinks, on the other hand, if taken safely, can indirectly fuel endurance athletes by providing them with a dose of carbohydrates during exercise. Be careful not to overdo it, however, and stick to one can per workout. It's still a good idea to consider other sweet, caffeine-free options so you can ride without discomfort. Once again, moderation tastes much better.

 For some people, excessive caffeine intake will have an almost immediate laxative effect, which is undesirable, especially considering how difficult it is to quickly remove a bib... As for energy drinks, they can be somewhat addictive, encouraging us to drink them even outside of training sessions. With added sugar cubes, unnecessary calories and energy fluctuations will only increase.

 Obviously, these drinks will not quench your thirst as well as a good glass of water would, and, as mentioned earlier, the more you drink, the more your system gets used to it, and the less noticeable the physiological effects will be.

Nothing is ever black and white, in nutrition as in other areas of life. By understanding these different factors, you will be able to make an informed choice that suits you, while ignoring food marketing that tries to convince you that critical thinking is not your cup of tea...

 Table 1: Recommended caffeine intake for ergogenic effects 

References

Davis, J. & Green, J. M. (2009). "Caffeine and anaerobic performance," Sports Medicine, vol . 39, no. 10, pp. 813-832.

Flinn, S., Gregory, J., McNaughton, L., Tristram, S., & Davies, P. (1990). "Caffeine ingestion prior to incremental cycling to exhaustion in recreational cyclists," International Journal of Sports Medicine, vol. 11, no. 3, pp. 188-193.

Franco-Alvarenga, P. E., Brietzke, C., Canestri, R., Goethel, M. F., Hettinga, F., Santos, T. M., & Pires, F. O. (2019). "Caffeine improved cycling trial performance in mentally fatigued cyclists, regardless of alterations in prefrontal cortex activation," Physiology & Behavior, no. 204, pp. 41-48.

Graham, T. E. (2001). "Caffeine and exercise," Sports Medicine, vol. 31, no. 11, pp. 785-807.

Larson, E. (2018). Exercise Performance and Perception of Breathlessness After Caffeine Ingestion in Cyclists, Appalachian State University,

Tremblay, P. (2010). "Taurine and energy drinks," Toxicology Information Bulletin, vol. 26, no. 1, pp. 14-18.

Waldron, M., Patterson, S. D., Tallent, J., & Jeffries, O. (2018). "The effects of an oral taurine dose and supplementation period on endurance exercise performance in humans: a meta-analysis," Sports Medicine, vol. 48, no. 5, pp. 1247-1253.