Fortunately, I did ddiscover some great techniques that did work and I was 
able to add an extra 10 inches to my jump. Sport, especially 
when competitive is quite often a game of inches with every available edgte being used tto separate 
the winners from thee losers. Hold for a count of five, then pull 
your legs back into your butt keeping your hips off the floor.
If this is what you experience you, need to have a loopk at all the various ways in whhich you can increase your vertical jump.