http://www.higher-faster-sports.com/verticaljumpfaq.html
There are many different ways to get to the same end result but the principles never change. Anybody that ever increases their VJ did so because they boosted either:
A: The force behind the movement (consisting of strength plus the ability to rapidly display that strength)
B: The efficiency of the movement
That's regardless of whether you trained with platform shoes, rubber bands, weighted vest, pool work, weights, or whatever.
Instead of haphazardly engaging in various training methods and maybe getting lucky and impacting one of those qualities, why don't we start with the end result and work backwards and find the quickest way to our end goals? So, what if we ask ourselves, "ok, what is the quickest direct way to improve the coordination in the vertical jump? What is the quickest way to improve the maximum force production in the vertical jump? What is the quickest way to improve the ability to rapidly display that force?
The answer to any of those questions is not difficult. For example, let's take the case of improving maximum force potential. Some would have you believe that they've invented some new age gimmick or training technique that is the end all and be all to develop that quality. But if we look at a sport where the ENTIRE SPORT is based on who can develop the most force. What sport is that? Powerlifting! If such and such gimmick was so effective for force production why aren't ANY top powerlifters using it?
Now how about taking the shortline approach towards improving the rapid display of force. If something is really a miracle for increasing this quality why isn't it being used by olympic athletes like high jumpers, triple jumpers, sprinters, and long jumpers? There is no shortage of information on this. Through 50 + years of research and observation it is quite clear that the most potent training methods to improve the rapid display of force are variations of the following:
1. MOST IMPORTANT: Practice the specific movement (jump if you're a jumper - sprint if you're a sprinter)
2. Lift light weights with great acceleration (use jumps squats and other various explosive lifts)
3. Engage in plyometric "shock" training (a.k.a. - depth jumps)
Two and three are frequently not even necessary.
Are there any secrets here? No!
So basically we can just put those things together and take the shortest path towards reaching our goals.
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so IMO, just get stronger, practise jumping a bit, but not so much it hurts your ability to get stronger, and you will be sorted. I doubt anyone who can full oly squat 2.5x their bodyweight or higher and practises jumping frequently has a vertical jump under 35 inches....