Caffeine is a very popular chemical that is used very frequently in American culture. It is actually one of the most psychoactive drugs used in the world. Like other substances, caffeine should be used after consideration and discussion with your health care provider.
Caffeine is an interesting chemical compound. Some research shows that the drug caffeine can increase the strength and contraction of certain special muscles in our bodies. Caffeine has also been shown to prevent the degradation of catecholamines, such as adrenaline and nor-adrenaline which are responsible for the "fight or flight" response that our body experiences when we work out, exercise.
In a dutch study, studying the effect of caffeine on the nervous system and muscles on our body, the researchers showed that caffeine caused higher arousal and increased acceleration of motor processes.
Although these studies show that caffeine can have these changes in our bodies, more studies need to be performed to describe the exact affect of caffeine on our bodies. Given that caffeine can be classified as a drug, you should discuss the use of the drug with your physician before you consume it since it can be harmful.