Spider legs do not have extender muscles. Therefore, after stretching their legs to jump, they jump using the hydraulic pressure of the blood, not their muscles.
There are multiple explanations for Spider-Man’s ability to hold on to walls and climb them.
In the original comics, Spider-Man was able to hold on to surfaces thanks to an electrostatic force.
In Sam Raimi’s trilogy, we see Peter Parker making small, very sharp hairs that allow him to grasp surfaces with his fingertips. In real life, neither of these methods has anything to do with spiders’ ability to climb.
Regarding spiders, Crawford said, “Every spider can climb hard brick walls using its paws. “But jumping spiders and other species have special microscopic hairs at the ends of their legs that allow them to cling to smooth surfaces.”
