All about caffeine

How caffeine affects performance

We have all been there. After a night of sleep-deprivation, or a time of intense stress, or as a last resort to keep us awake… our tired hands reach for the kettle and we brew ourselves a nice, strong cup of survival juice: coffee.

Or maybe, if you are like me, coffee is an absolute pre-race or pre-game must-have.

According to the ISSN (International Society of Sports Nutrition) exercise and sports nutrition review update, an ergogenic aid is “any training technique, mechanical advice, nutritional ingredient or practice or psychological technique that can improve exercise performance capacity or enhance training adaptions”.

Today we are taking a closer look at caffeine as ergogenic aid.

I decided to write this article after I got some questions regarding why some athletes drink coffee before workouts and races. I think it is important to talk about caffeine because it is something that is dose-specific, not only to performance but also to doping protocols and athletes need to be educated and empowered on how much they as INDIVIDUALS need to perform and stay within safe ranges. Always remember that what you put into your body is your responsibility (and this applies to every type of ergogenic aid or supplement you may consider using).

In a review published by the ISSN on caffeine and performance that examined numerous studies on the subject, it was concluded that caffeine effectively enhances sport performance in trained athletes when low to moderate dosages of about 3-6mg/kg is consumed.

However, reactions to caffeine can differ between individuals, and in some cases increase some anxiety and heart palpitations before competitions, and this should be considered before taking caffeine before events. People react differently to caffeine, and in some cases the effects of caffeine can be negative or neutral.

HOW IT WORKS

Caffeine has effects on your central nervous system by acting as an “adenosine receptor antagonist”. Adenosine plays a role in the regulation of your sleeping and waking cycles. While you are awake, it accumulates in the brain and eventually causes drowsiness, which signals to your body that it needs to slow down and rest. When you have caffeine in your system, it increases brain activity, makes you feel more energetic and may decrease your perception of fatigue. In other words, it enables you to go harder for longer before you fatigue. This is the most significant action of caffeine.

Another possible explanation for caffeine’s ergonomic effects is that it increases β-endorphin concentrations, which has analgesic properties and this may lead to a decrease in your perception of pain.

In addition to this, the performance benefits of caffeine can be attributed (to a lesser extent) to the fact that it can “spare glycogen” in the muscle by increasing free fatty acid mobilisation.

CAFFEINE TIMING

Although most of the studies followed a protocol where caffeine was ingested about 1 hour prior to activity, the effects of caffeine can be seen within 15-30 minutes.

Caffeine concentrations are decreased by 50-75% within 3-6 hours of consumption. It is important to time caffeine intake in such a way that it does not disrupt your sleep! Caffeine can benefit recovery by enhancing muscle glycogen resynthesize, but not getting enough sleep is counterintuitive to the recovery process.

WHO BENEFITS FROM CAFFEINE?

Caffeine has shown benefits for sustained maximal endurance activity, and has effectively benefited time-trial performance. It also has shown performance benefits for athletes participating in prolonged, high-intensity sports like rugby, hockey and rowing, but this effect was specific to trained/conditioned athletes.

CAFFEINE AS A DIURETIC

Concerned about the fact that having caffeine will have you running to the loo mid-session or race? You will be glad to know that science does not support the idea of caffeine having the same diuretic effect during exercise as it does during rest. Several studies have failed to prove any change in the amount of water lost, sweat rate or negative change in fluid balance following caffeine ingestion.

WHAT ABOUT DOPING?

Because caffeine can enhance performance, the IOC (International Olympic Committee) mandates a limit of 12µg of caffeine in the urine, which equates to approx. 9mg/kg. That would be about 4-6 smaller cups of brewed coffee containing about 100mg per cup, depending on gender and body weight.

It is INCREDIBLY important to know how much caffeine you can ingest without going over the allowed threshold! NOTHING is worth risking testing above the allowed threshold, so when in doubt, rather be safe than sorry.

Also, remember that the caffeine content of drinks depend on how strong you make it. It should be noted that some retailers sell coffees or espressos that come in extra-large containers with extra strong varieties of coffee. Some of these brews can provide 500-1000 mg of caffeine at once. So, always be aware of the amount of caffeine you are putting into your body. If you are unsure about how to calculate safe amounts, consult a registered dietitian to help you do that.

WADA (the World Anti-Doping Agency) does not put caffeine on the list of banned substances, but has included it as part of the monitoring program in order to “establish patterns of misuse in athletic competition”.

HOW MUCH LEADS TO PERFORMANCE?

When caffeine is consumed in low-to-moderate dosages – about 3-6mg/kg – performance enhancing benefits can be perceived. However, higher dosages above this range does not lead to any further benefits. Therefore, multiply your body weight by 3-6 to get the amount you need to reap the benefits. Below is a summary of how much caffeine different products used frequently in sport contains.

References:

Goldstein, E.R., Ziegenfuss, T., Kalman, D., Kreider, R., Campbell, B., Wilborn, C., Taylor, L., Willoughby, D., Stout, J., Graves, S.B., Wildman, R., Ivy, L.J., Smith, A.E., Antonio, J. 2010. International society of sports nutrition position stand: caffeine and sports performance. Journal of the International Society of Sports Nutrition. 7(5):1-15.

Kersick, C.M., Wilborn, C., Roberts, M.D., Smith-Ryan, A., Kleiner, S.M., Jager, R., Collins, R., Cooke, M., Davis, J.N., Galvin, E., Greenwood, M., Lowery, L.M., Wildman, R., Antonio, J., Kreider, R.B. 2018. ISSN exercise and sports nutrition review update: research and recommendations.

Journal of the International Society of Sports Nutrition. 15(38).