Interesting, didn't know about this sport. Geez that is quite some power in that ball they are throwing.

Definitely makes me think how important lag angle is

Archaic Arms wrote on Apr 1^st, 2021 at 11:48pm:


the motion of jai alai sidearm throws (170mph+) looks a lot like slinging,I consider length 60 -70cm low for records. I think Luis gets 52m/s with 200g (270J), usually when lowering mass joules lower too and velocity goes up, I don't think Luis could get the same speeds (76m/s) with the same projectile (130g 375J), maybe just reach it and there is a team of people passing 170mph repeatedly.

yes other sports are also interesting, e.g. some pitchers have reached 100mph ~45m/s 145g 146J by hand which as I understand a lot of people will find difficult to do with a sling. But other sports have higher budget which means better selection & better training and focus. I dont really know but I'd say Jai Alai nowadays has a much lower budget than baseball and the track n field sports, making it more comparable to slinging.

correction on the video conclusion:
It is not only the extra muscles and the stiffness of the cesta that help reach those velocities.
After more observation of the throws by professionals* I would say the high velocities are achieved also by the conservation of angular momentum. Going from a high radius early on the throw to a lower radius late on the throw before release. this means that the short length of the cesta is actually balanced to have a short late radius and a long length of early acceleration.

early in the record throw (underhand) the cesta pulls the ball towards the ground in an almost straight line.
after that the arm pulls and rotates the cesta changing the ball direction almost 90degrees.
the trajectory curve  resembles a J
reminder L=mur

could this be applied to slinging?
it's already applied to slinging but to a smaller degree and there are limiting factors because the use of a string creates different curves and different changes in radius.
I think I've seen the most pronounced use of it with AA using short slings and heavy stones. Initiating the wind up with a long arm arc motion and ending with the arm closer to the body.

generally it is used by everyone to some degree when we are in the cocked position before turning the body we tend to raise the shoulder to increase radius and then as we pull part of the acceleration is due to the decreasing the radius.

In the past months I haven't practiced because I dont have time. But I am more and more starting to believe there is great potential for speed in pirouette styles where the angular momentum of the body is greater and there can be greater manipulation of the curve of the projectile even with longer slings.

In simple styles with a step, using a long sling nullifies the effect our arms have on the change in radius through the throw, and that seems to be the reason we settle for a particular range of sling lengths.

I hope that those who read this know at least that the radius of curvature is not the sling length or cesta length. Radius of curvature has to do with trajectory of the projectile. see a visualization in the intro and outro of this video https://www.youtube.com/watch?v=ZCJfq77sFE8

*edit: throws by professionals https://youtu.be/N_KFXjOJHOk?si=P8t2j2jXtaQsHU9W