When it comes to nutritional supplementation for athletes, there are only a few (legal) substances which have decent scientific evidence for their improvement of performance. We’re not talking about massive improvement, but there are some supplements which do provide statistically significant benefit in the right scenario. Perhaps the most often used, and misused, in this category is caffeine.
Caffeine is found in coffee and tea, making it the most widely-consumed psychoactive substance on the planet. It is estimated that human beings ingest, on average, one serving per person per day across all cultures. Physiologically, caffeine acts at a neurological level, decreasing the activity at adenosine receptors. Adenosine causes relaxation and a sedative effect, so blocking this will lead to a heightened sense of alertness. Caffeine also leads to secondary benefits at a muscular level, aiding in contraction of the muscle fibers.
As an athlete, the effects of caffeine can be harnessed for modest performance gains. Again, these are not huge benefits, but they can be significant. I bet I know what you’re thinking. If caffeine is legitimately performance-enhancing, why is it not banned by WADA? Well, it was conditionally prohibited until 2003, but it is hard to justify banning one of the most commonly consumed products in the entire world! Additionally, for a substance to be banned by WADA, it must meet 2 of these 3 criteria:
1. It has the “potential to enhance or enhances sports performance”
2. It is "an actual or potential health risk to the athlete”
3. Its “use violates the spirit of sport” as outlined in the WADA Code
* “Substances or methods which mask the effect of prohibited substances are also prohibited.
Caffeine only meets one of these three criteria. However, WADA maintains a “watch list” of substances that are closely monitored despite being legal. Items on this list are reviewed each year and could face prohibition, but that is unlikely to happen with regard to caffeine.
Chances are, you are already using caffeine. Maybe you drink coffee or tea, or perhaps you are using caffeine gels or even tablets. From a performance standpoint, do you know why or how to use it?
Effects of Caffeine on Athletic Performance (not all beneficial!)
- Increases aerobic capacity
- Increases power output
- Increases available fuel (free fatty acids and blood glucose)
- Decreases perceived exertion
- May improve reaction time
- Decreases fatigue
- Increases heart rate
- Increases anxiety
- Increases body temperature
- Increases lactate production
- Can lead to insomnia and poor recovery
Dosing - Amount
- Needs to be individualized. Habitual consumption can lead to tolerance.
- Benefits generally shown to occur at doses of 1-3 mg per kilogram of body weight. For most, that works out to roughly 100-200mg. That is roughly the amount of caffeine in a cup of brewed coffee.
- Moderate doses (as above) are all that is needed. More is not necessarily better, as there are potential performance detriments that can occur.
- Caffeine can exacerbate some common medical conditions. You should not use caffeine without first consulting with your physician. This is not just the standard medical disclaimer! It can cause problems for many people. Talk to your doctor.
Dosing - Timing
- Timing depends somewhat on the purpose.
- Central nervous system stimulation (wakefulness and attention) occurs relatively quickly after ingestion.
- Muscular effects lag a bit.
- In general, it is recommended that caffeine be ingested roughly 60 minutes before it is desired to take effect.
In general, caffeine for athletic pursuits is best reserved for competition. I don’t see a significant role for training, other than enjoying a cup of your favorite espresso before a ride or run. One caveat though, is that you should always practice your nutrition and supplementation strategy before the race. As there is some individuality to caffeine use and its effect, do take the time to hone your strategy in training before you toe the line of the big race.