Hysterical strength

Hysterical strength is when a person can do something really surprising and amazing with their body, like lifting something really heavy or running really long distances, even though they usually don't have the strength or endurance to do it. It's called 'hysterical' because you don't do it because you want to, it just kind of happens when you feel like your life is in danger. It's like your body does something it never could before because of fear.