Has this ever happened?

So, I was reading an old Fortean Times when I stumbled across a reference to women and children who, in times of panic, gained superhuman strength and lifted cars or other heavy objects. This certainly isn't the first time I'd heard of this--I suspect most people believe that bursts of superhuman stregth occur under the right circumstances. But has there ever been a real, documented case of this happening on film? It seems like if people really go gain superhuman strength in panic situations, we would see that caught on police chase film or something. There are thousands of rescue situations caught on film each year. Can someone point me to proof that panic strength is real? Or is the last second surge of superhuman strength just a myth we embrace to comfort us?