There is only 1 way to win > fairly and on your own merit. Each and every time. Have integrity!
From my own experience and upbringing, I will say do not hold back like I did to fit in or when people took from me without my permission. The only way to handle a bully is to stand up to them. Bullies come in all shapes. You cannot clean someone up of their own negativity — that is their job and being a doormat does not mean you escape it. You cannot make someone good. That person has to come to you good!
Holding yourself back just means you did not use your own abilities nor did you enjoy the journey, discoveries and thrills of your own successes.
Go all the way! Do not hold back. See what you are made of.
And lastly, when you lose, do it gracefully. Enjoy the game.
True freedom lies in going all the way and seeing what you are made of and knowing the only person you are competing with, is yourself. The goal is to be a better version of yourself and to grow! : D