Is Achilles tendon long or short?

Shit, it's 90, 13 years old! You're provoking me. I can't touch the board yet, 17, but what I want is that technically, the rebound is average. We are idols, and I like to imitate his movements. Of course, the longer the heel, the better, and it will jump higher. By the way, Kobe's heel is several centimeters longer than Jordan's. How do you think it's better to do it or short it?