Shivering in the legs on seeing someone fight, urge to stop it - Online Doctor Chats

Doctor :   hi
Doctor :   Dr.XXX here.
Doctor :   please proceed with your health query.
Doctor :   how can I help you?
User :   Hi Doc, need your expertise advise.....this might be a weird question but why do my legs shiver when I see someone fighting and there is a big urge to stop te fight by intervening in between
Doctor :   it could either be due to anger or anxiety. does this happen all the time?
Doctor :   what are your thoughts in such situation?
User :   I initial thought is to stop that fight....Is there a way to stop this feeling?
User :   *my
Doctor :   If it is a natural response coming, then it cannot be stopped. if it is due to any past experience, then you can train yourself with help of counseling
User :   it's very unlikely that it is due to some past experience, however, it seems more like a natural outcome
Doctor :   then it might be difficult to control. However you can try with counseling with psychologist, it may help you.
Doctor :   it is anyways a good response that you want to stop people from fighting
Doctor :   unless it is bothering you or affecting your day-to-day life, you can leave it alone
Doctor :   are you there?
Doctor :   have you followed what I have said?
User :   ok doc, I have followed you,,,,,will surely try practicing it....thx a lot
Doctor :   is there anything else I can help you with?
User :   thats it...thnks a lot
Doctor :   thanks for consulting me. bye for now.