Adrenaline stimulates the release of endorphins, which are natural pain relieving compounds. They bind to opiod receptors in the brain, which produce analgesic effects that diminish the perception of pain, Essentially. It's like smoking dope.... or taking opiods. (roxies, oxys, hydros etc.) It influences the central nervous system by heightening alertness and cognitive focus... meaning you're in a state of heightened awareness and fight or flight, so your brain prioritizes immediate survival actions over processing pain signals. The sympathetic nervous system, when adrenaline is activated, further modulates neural pathways, reducing those that are receiving transmitted pain signals through the spinal chord. The neural suppression of pain ensures that the individual can maintain physical performance and focus without hindering due to discomfort. The redirection of blood flow also plays a crucial role. Adrenaline causes vasoconstriction (the narrowing or constriction of blood vessels by small muscles in their walls) in skeletal muscles. This enhances blood flow to areas needed for rapid physical response.