What is the Physics Behind a Jumping Spider's Impressive Leap?

[Manoj]

I recently viewed this video:



shttps://www.youtube.com/watch?v=FhpL5h8sEHo (without the s at the beginning)
i really don't understand how the high blood pressure acts on the legs. The physics i understand is that - A body to do some action needs to put opposite force on the stationary body for relativistic action, yearning a reaction force on the body itself thus providing motion. But you can see that the spiders legs are frail, weak, then a sudden high release of blood would destroy the legs. And even for that high blood preassure, the legs must have enough strength to bear the high pressure, which it doesn't look like it can.

I know impulse provides large forces in short time to provide more energy, but does it concern an area of action? I suppose the impulse acts on a point of their legs to generate more pressure to lift, but it doesn't even look like its been concentrated at a point while it propels. It seems like the power to jump is coming from somewhere else.
Can someone please explain me the science behind its jumping? It would be really grateful for the community and me, as this jumping nature keeps bugging me.

 

[A.T.]

... the spiders legs are frail, weak,...

https://en.wikipedia.org/wiki/Square-cube_law#Biomechanics

 

[Lonnie Klein]

Thanks for sharing the video .

 

[256bits]

the high pressure

I don't know how they mechanism in the joints actually works for their legs to extend, but high pressure certainly doesn't mean like 100 psi.
If you take one of those long tubular balloons and blow in it, you can see the rigidity with comes about from the slight pressure difference from atmospheric.
Something similar to that I am assuming from watching the video.
I don't have a spider here to dissect to see if there is such a structure in the legs that would do what they say could be the reason for the capability of the jump.