I recently attended a workshop on the Kinetic chain followed by a workshop on the feet. This was a very interesting 2 hours. First was a review of the importance alignment plays in power production of the muscles. If your alignment is off by a centimeter in either direction there is a measurable loss of power generated by the muscles.
How to increase your vertical jump?
First off I am assuming that you have gone and addressed any alignment issues in the kinetic chain. (The Kinetic Chain is essentially everything in the body that relates to movement). If the kinetic chain is out of balance you simply will not be able to maximize your potential to generate power under any circumstance. So if you have not had a movement assessment to ascertain if there are movement issues due to muscular imbalances or improper form, do this first. Correcting muscular imbalances will not only improve your ability to produce power in your muscles it will prevent future injury from occurring. Misalignment or imbalances in the muscle producing inefficient movement patterns will lead to injury and a loss of power in the muscles. This is due to improper length tension relationships in the muscles.
Having balanced muscles and movement patterns supported by your anatomy will allow you to maximize your potential and increase power output in the muscles as well as, prevent injury. Once balance is achieved your full potential is available to you in your vertical jump or any other measure of power, speed, or strength you could imagine.
The number one exercise to improve vertical jump is the squat. Second to that is building strength in the calf muscles. After proper form is mastered a foundation of endurance, strength, and stability can be built. Then using explosive exercises like plyometrics reduce your reaction time and help generate explosive power.
The most important thing is to start slowly and make sure that form is correct when doing any exercise, especially those that require loading the muscles with weight. Proper form beats number of reps and total pounds every day of the week. So movement pattern and alignment are addressed first then add in endurance, strength, power, and explosive power training. Good Luck with your vertical jump and stay safe