imo its up to debate.
my opinion that yes, physical size and biology is the biggest factor in how good a persons chin is. in my experience keeping your eyes open can help somewhat, now i know it sounds ridiculous but hear me out. you get hit your sense of balance is gone from your inner ear, its a scary feeling but if you see where you are that split second you can allows you to catch your footing instead of falling. who knows maybe im wrong, just in my experience.
the factors you can control are where and how hard you get hit, blocking/ducking/dodging/weaving or even choosing to take it right on the forehead. hardest punch ive ever taken i took right on the forehead, didnt even knock me down.
also ur footwork is what determines how hard you are hit, unless ur moving into their power your movements make you harder to hit and when you get hit its more likely to be glancing and less damaging
If a law is unjust, a man is not only right to disobey it, he is obligated to do so. ~ Thomas Jefferson
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