Alba, who has two children, admits she also trains for her action scenes away from home as she thinks fight scenes are not "appropriate" for them right now, reported Us magazine.
"I don't even do fight training at home. I go to the gym for that. And they won't see this movie. It's not appropriate," she said.
The 35-year-old star recalled a particularly eventful day of shooting on the set of "Mechanic: Resurrection" where she accidentally punched a stunt man in the groin.