do somebody/yourself an injury

do (oneself or someone) an injury

To do something that harms or injures oneself or someone else. I think you'll do yourself an injury if you try that risky skateboard trick. You sure did your brother an injury by including him in that dangerous game.
See also: injury

do yourself an injury

suffer physical harm or damage. informal
See also: injury

do somebody/yourself an ˈinjury

(often humorous) hurt somebody/yourself physically: I nearly did myself an injury carrying those heavy suitcases.
See also: injury, somebody