I think this is right tag
In: 52
The other answers have come close but missed out explaining why. Humans are usually operating on stay alive for 100 years and keep your energy expenditure even across the whole day, doing anything that risks either is hard.
Panic responses generated by adrenaline change that focus to survive the next minute. So amongst the extra blood flow, oxygen, and lack of higher order cognitive functions, it significantly changes the psychology of how you utilise your muscles. Rather than the usual of a small percentage of your muscle fibres distributed across the whole muscle firing when you use a muscle, it makes the whole muscle fire synchronously. The first method controls your force output, and also allows for endurance of your body. The second risks snapping your bones or tearing your muscle off the bone, the average person will do one of either without the conditioning of regularly lifting heavy weights. Despite the risk of damaging yourself it can be worth it to keep you alive.
Powerlifters and olympic weightlifters have to train themselves to support full muscle firing and get around the psychological block that prevents you from doing this. So, under adrenaline you’re jumping into temporarily being an olympic weightlifter and can do feats like push a tractor off your dad as a toddler, stop a car rolling down a hill towards your child, flip a car on its side to free somebody stuck underneath, but without the conditioning these real life ‘superheroes’ all got spinal damage from their own muscles.
So in summary, a psychological block being removed allows you to be insanely strong but also gamble over if you cripple yourself by moving
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