In our daily life, we rend to do some things which are easy ,but can make us feel relaxed. The only disadvantage of these things is that they easily lose effect after doing them for few times. For example, you just enjoyed a fantastic meal yesterday that made you very happy, but if you still enjoy it today, will it still make you feel happy. In that case, we are conteolled by one special kind of chemical called Dopamine. The chemical can make everyone feel excited but can't last too long. Meanwhile, another chemical in our boby has the same effort but it can last for longer time. It is Endorphin which is usually hard to create in our bodies. The process of creating is is very complex. We should experience some tough time at first. For example, running or working out. Everyone has might experieced the feeling that we were tired while doing exercise, but if we kept it up, finally we would feel relaxed a lot. It is related to Endorphin relaesing during exercise. The better thing is that we find that we become patienter and stronger by doing physical exercise.