Caffeine does not actually give us energy. It just makes our body numb to energy or the lack of energy, right? So we use caffeine to feel less tired and we end up making ourselves more tired because of all kinds of other things. There's a balance between two hormones: insulin and glucagon. Insulin is anabolic; it builds things like cellular machinery. If you play games like RTS based on insulin, your strategy will turn away from building up sugars into glucose that can't be used for activity.