Caffeine is a central nervous system (CNS) stimulant of the methylxanthine class of psychoactive drugs.
It is effective in increasing the state of wakefulness and suppressing sedation.
Reliable research suggests that caffeine intake results in a significant increase in power output in both trained athletes and sedentary persons. As a result of this power output as well as caffeine’s ant-fatigue effects it seems also to benefit anaerobic cardiovascular exercise. However, it has been shown that caffeine can increase aerobic exercise capacity as well.
Some studies have suggested that caffeine possibly increases the feeling of well-being and mood. It is felt that this mood improvement may be as a result of fatigue reduction or from the increase of Serum catecholamines (adrenaline, noradrenaline).
Limited evidence suggests caffeine may also reduce the risk of: Parkinson's disease, liver disease, colorectal cancer, type 2 diabetes and dementia.
How it works
Caffeine’s main mechanism of action is to antagonize adenosine receptors. Adenosine causes sedation and relaxation when it acts upon its receptors, caffeine prevents this and causes alertness and wakefulness.