Caffeine is used by nearly 100 percent of adult men and women, making it the most widely used stimulant drug in the world. Caffeine has also become more popular amongst endurance athletes as an ergogenic (energy generating) aid since it was removed from the list of banned substances list in 2004 (although it is still banned in high quantities). While research into the performance enhancing effects of caffeine is controversial, many athletes claim caffeine enhances performance.
Effects of Caffeine
Caffeine has a stimulating effect on the central nervous system (CNS), reducing the sensation of fatigue, perception of work effort and even pain. Moreover, caffeine improves mental acuity, focus and technical skill during and after strenuous activity or fatigue. Caffeine is believed to enhance fat utilization in the body and has also been shown to effectively increase time to exhaustion during endurance activities, as well as sprint, power and strength performance.
A number of studies that used runners, swimmers or cyclists found that caffeine did tend to be an effective ergogenic aid, but the improvement in performance depended on many factors, including:
- duration and intensity of the activity
- how much caffeine you ingest
- when you take it
- whether you are a habitual caffeine user (the body quickly develops tolerance for caffeine and effects may be diminished in habitual users)
Some studies indicate that caffeine might be most effective in restoring high intensity performance rather than enhancing it, which is a good thing for endurance athletes. There is less information about the effects of caffeine in ultra-endurance events such as Ironman. Pre-race caffeine may be beneficial though, because the longer the race, the more important fat is as a fuel.
A small study in the International Journal of Sports Nutrition and Exercise Metabolism suggested that caffeine may help to prevent muscle soreness during and after exercise by blocking the activity of adenosine in the body, preventing activation of pain receptors.
Side Effects
Although caffeine has not been shown to significantly alter water balance or body temperature during exercise, dehydration is a potential concern because caffeine is a mild diuretic. Some athletes may also experience abdominal cramps and diarrhoea related to the large intestine contractions caused by caffeine. The combination of dehydration and cramping can have particularly detrimental effects on performance.
Caffeine can also produce restlessness, headaches, and irritability. Caffeine elevates your heart rate and blood pressure and can disturb sleep patterns.
The decision on whether to use caffeine as a performance enhancing aid rests with the athlete. Though caffeine has some benefits in relation to exercise performance, risks have been documented. Most problems seem evident with very high consumption. As with everything else, moderation is the key to healthy caffeine consumption. Further research is needed to clearly determine whether the performance-enhancing benefits of caffeine outweigh the potential risks.
Using Caffeine as an Ergogenic Aid
If you are an athlete who is already accustomed to caffeine (perhaps in coffee or tea), you may want to consider the following with regards to caffeine as a performance enhancer:
- Decrease your caffeine use or abstain completely for 3-7 days before your race.
- If possible, ingest caffeine 3-4 hours before the race for maximum effect on fat stores. Peak blood levels occur within 45-60 min after ingesting caffeine, so use this as a guideline just before the race. Use should be continued during competition for it to be most effective.
- Moderate quantities (3 – 6 mg.kg-1 body weight) have been shown to be most effective in athletes
- Consuming caffeine either in pill form or in a carbohydrate beverage seems most effective, as substances in coffee may diminish caffeine’s overall effects
- Make sure that you have used caffeine extensively under a variety of training conditions and are thoroughly familiar with how your body reacts to this drug. Never try anything new on race day
