Vincenzo: Squat. Squat lightish and fast and squat heavy as well. And practice.
Eddie, in 1968, at the Olympics, a study was done to determine the best average vertical leap and short sprint (30yd, I think) of all athletes. The weightlifters (including the SHW ones) beat everyone else in both (Including High Jumpers and sprinters). So I wouldn’t be surprised if there are a few verticals approaching 40" there.
I don’t have the reference for the study, maybe Kelly or someone can help out.