Caffeine has been shown to have many positive effects on performance. These include the increase usage of fat stores during endurance exercise, increased force production from the muscle, reduction in perceived effort during hard exercise, stimulation of adrenaline and improved alertness and reaction time.
It is unclear exactly how caffeine improves performance but it is likely to be due to a reduction in the perception of effort or fatigue, as well as direct effects on the muscle. There does appear to be individual variations in the effect of caffeine on performance. Sources of caffeine include:
Food or Drink
Caffeine content (mg)
Instant coffee (250 ml cup)
Brewed coffee (250 ml cup)
Tea (250 ml cup)
Green tea (250 ml cup)
Milk chocolate (60 g)
Coca Cola (375 ml can)
Red Bull (250 ml can)
Concerns Associated with Caffeine Use:
There is considerable individual variability in the response to caffeine. Some people will gain an advantage from caffeine use, while others may experience no effect or negative side-effects from the same caffeine dose. It is VERY important you trial the caffeine dose using the guidelines provided during a training session before using it in a race.
If you are caffeine sensitive and you take high doses, there is the potential to cause increases in heart rate, impairments to co-ordination and technique, and sleep disturbances. These concerns add to the importance of finding the lowest effective dose of caffeine that can be used to achieve a performance enhancement. More is not always better!!