Athletes are forever striving for ways in which to compare themselves to other athletes and prove superior. We measure ourselves in miles run, weight lifted (or pressed, or pulled), laps completed, and height jump (among other things, of course). There are reasons to increase these things ranging from improvement of your game to sheer competition, but any reason is reason enough to better yourself.
If you are a basketball player, a volleyball player, or a participator in track and field, you might be looking for ways to increase your vertical jump. The first step in any training program is to find out where you are already. Stand on a flat surface in front of a wall, and reach up as high as you can while flat-footed. The spot you reached is marked for reference, and is known as your standing reach. The next step is to take several (usually three) jumps from a standstill and have your reaches marked at the peak of each jump. The difference between the two is known as your vertical jump. It is important to remember that you are jumping from a standstill, and not from a run-up.
Now that you know how high you can jump already, you are ready to increase your vertical jump. Your vertical jump is a measurement of how high you can lift your bodyweight off the ground. To do this requires producing power, which in physics is measured as power equals work over time (P = w/t). In sports like this, the equation means that you must increase your strength and speed in order to jump higher. Strength training will take you the first part of the way.
Strength training does not need to include upper body training if you don’t want to bulk up above the waist. The most important muscles to improve are the p-chain, which consists of the hamstrings, calves, lower back and glute muscles, and your quadriceps which are not part of the p-chain, but which are possibly the most important muscles to train for your vertical jump. Two of the most beneficial lifts that you can do for yourself are the full back squat, and the dead lift. Head to the gym and ask about other lifts that will help with the p-chain muscles and your quadriceps.
The second factor that you will want to increase is speed, but this is not important at all compared to strength training. Without the strength to get yourself off the ground, speed is unimportant. After you have focused on increasing your strength, though, increasing you speed might give you a little extra edge on your vertical jump skills. Your speed is a measure of how fast you can exert force, and in the vertical jump there is no way to build up speed before the final leap. There is a miniscule period of time (much less than a second) in the vertical jump for you to exert your force and gain height in your jump. It is important for you as an athlete to be able to exert the maximum amount of force in the shortest period of time possible.
They two types of exercise that are best for increasing the speed aspect of your vertical jump are plyometric exercises (exercises which allow you to absorb the more energy during the counter movement, or eccentric contraction of an explosive action) and explosive training like jump squats or power cleans.
If you are serious about increasing your vertical jump, a few hours a week in the gym doing the right training could be your ticket to better performance.