Weird thing that bothers me in movies

I just watched Mission: Impossible 4.  Totally unrealistic, but I can handle it, because it’s supposed to be over the top.  Scaling a building?  No problem.  Jumping onto moving cars?  OK.  It’s the realistic parts that bug me.  There was a 60 year old scientist battling an agent from the team in a fight to the death.  It drove me nuts.  I can handle aliens, vampires, fill in the blank, yet the thought of man close to retirement beating ass is too much.  Much like the hot chick that beats up five Russian mafia guys or special forces soldiers.  I have no doubt a woman can toss a punch after some training, but the thought of Jessica Alba/Drew Barrymore taking a full on overhand right to the grill and shrugging it off is just silly.  Unless she’s a superhero.  No problems there whatsoever.