To replay the video just click and drag the time bar back to the start.
Broad Jumps are a good exercise for improving reactive strength and reducing ground contact time for two legged jumpers.
The idea with broad jumps is to jump for both height and distance whilst minimizing ground contact time. When the goal is an improved vertical jump however I believe this exercise is more effective if you place greater emphasis on height over distance.
Broad jumps are a good staple of vertical jump training, but for truly astounding results you need to try something different. If you want something a lot more effective than you need to check out Game Changers: The Greatest Vertical Jump Exercises Known To Man. These exercises produce jump training results far beyond the regular drills. To find out more click on the link.