Russell Crowe may have given to the poor in “Robin Hood” … but what he really needed was to take time off for himself — ’cause he fractured both his legs on set!

The actor sat down with People for an interview published Saturday … and, he revealed he suffered a pretty serious injury while filming the movie almost 15 years ago.

The way RC tells it … he was performing a stunt where he jumped off a castle gate onto uneven ground. It was late, and Crowe said they probably rushed the prep before the stunt — deciding not to bury a crash pad to land on.

Lo and behold, Russell landed and said he felt something akin to an electric shock shoot through his body … but he managed to struggle through the scene since the epic battle sequence was already in full swing.

And, Russ said he didn’t stop struggling on the movie … saying he had trouble even walking over the final month of shooting for the action-adventure film, though he didn’t take a day off.

Fast forward about a decade, and Crowe said some pain in his legs sent him to the doctor … who X-rayed him and asked when exactly he’d broken his legs ’cause he could see the residual damage in his shin bones.

Crowe said he thinks a year off he took between finishing “Robin Hood” and training for “Man of Steel” let his legs naturally heal enough to overlook the pain … proving the man’s kinda superhuman himself.

BTW … Russell’s new movie “Land of Bad” came out yesterday — hopefully, he’s not finding out about a couple broken elbows in 2034!!!