Been there, seen it done it !
When I was young, I was like you. I was strong, knew I was strong/young/fit/fast. and was used to beating people by being stronger /faster.
When I kime'd my chudan punch against your block, at exactly the right moment last night, instead of the shock being generated from your block to my punch, I managed to reverse the process and generated the shock to your block. Result being that because you weren't in shimme, the whole body muscle system was upset. To compensate, your Latissimus dorsi said "Sod this for a game of soldiers" and went into spasm.
Did this once to Lloydie on a block, I don't do it very often because of the damage it causes.(With you it wasn't intentional but accidental because you get my adrenaline going, being so BIG,YOUNG,STRONG,and DANGEROUS.)
Gave me a great idea for the final lesson though, and I taught the class a lesson on generating "kime" without
force = mass x acceleration. Whereas mass and acceleration are irrelevant compared to interaction with immoveable object = floor.