Shutter speed is essential here for freezing the action. Not sure what it should be for people jumping… but I’d reckon you’d want to be getting it quiet fast… 1/250th or 1/500th of a second or faster maybe (anyone else feel free to correct me).
Any idea what the shutter speed was on the shots?
What I would normally do in this sort of situation would be to shoot in Aperture Priority mode and adjust the aperture value and ISO to values that give me the required shutter speed… don’t go too low on the aperture or your depth of field may be too shallow.
Others might use Shutter Priority mode… where you dial in a shutter speed and the camera works out the aperture for you.
The best way to get fast shutter speeds is to shoot in good light. The less light, the longer your exposure times will be.