it is important to learn how to keep your emotions in check as martial artists we must stay focused as people we are lead by our feelings when we feel that your hearts is telling to do something some times it might not be the right thing for example as martial artist we are taught to defend yourself when we are put into a position were we have to use what we learned the first thing that happens is you panic .when you learn who to control that you can calm your mind then focus at the task at hand and take control the same thing when your are angry you have to control your emotions.when your happy sad fearful when your training just stay focused.the most important feeling to control is fear it can it can work for you or against you.there is an old saying the only thing to fear is fear itself.