Caffeine as a naturally occurring drug has a very rich history. It has travelled around the world in mysterious ways through coffee beans. It originally required specified equipment to brew, but with the invention and popularisation of instant coffee, it has truly reached the masses. While many drink coffee and derived beverages for enjoyment, it has physical benefits too. Athletes and any other population can reap the performance boost that caffeine provides. The way in which it works is fascinating. Caffeine moves through the blood into the brain (only a few molecules are able to cross this barrier). Once in the brain, it attaches to receptor sites of the molecule called adenosine. Adenosine is responsible for the perception of tiredness and fatigue. Since caffeine molecules have blocked the sites, adenosine is not able to attach there and thus the feeling of fatigue is alleviated. This is exactly why people drink coffee to pull an all nighter before an exam. Caffeine has been found...