Board Thread:The Flash discussions/@comment-13895380-20151024171607/@comment-3423279-20170313124402

If a human sized entity punched someone going Mach 1 the entity in question would turn that human into a disgusting smear on the wall, Barry generally does all he can to avoid killing anything, so of course he doesn't super speed smack them.

His reaction time could easily be that, in the moment, he has fantastic reflexes, but when he isn't in the moment he is just as human in that regard as the rest of humanity.

Or, anytime he experiences pain/needs surgical assistance, Barry is feeling that pain for hours from his perspective.