Finally, to make things even more complicated, it is likely that the roles of the lower body muscles may differ according to if: (1) the jump is maximal or sub-maximal, (2) long-term training has occurred, and (3) the individual has a “hip-dominant” or a “knee-dominant” technique. Indeed, the vertical jump is more dependent upon the hip extensors in maximal jumps, compared to in sub-maximal ones. And after long-term jumping training, the increase in the amount of work done in the jump by the hip extensors is related to the increase in height, while the increase in the amount of work done by the knee extensors is not.
To start the test, you need to stand with your right side against a wall. If you have access to a chalk board or a vertex (the measuring tool used by biokineticists), it makes this easier, however, you can use an outside wall. For the first marking, stand in your training shoes with your right hip against the wall. Reach up with your right hand to touch the wall at the highest point possible (while keeping your heels flat on the ground). Mark this point with chalk, as this is your “standing height.”
High pulls can also be done using a dumbbell or kettlebell,. When doing so, position the weight between your feet and pull with one arm at a time (switching arms halfway through the set). A trap bar (aka, hex bar) is also an option, particularly for individuals who have a hard time keeping the lower back flat; the trap bar allows the hands to be positioned behind the shins to help pull the shoulders back.
When tendons elongate to a greater extent during a jumping movement that is preceded by a countermovement, the muscle lengthens less. This produces two effects. Firstly, the greater elongation of the tendon means that more elastic energy is stored during the countermovement, which is then released in the subsequent jumping phase. Secondly, the smaller elongation of the muscle means that countermovement depth can be greater for the same shortening velocity in the subsequent jumping phase, because the muscle never lengthened that much to begin with. Since shortening velocity determines force, this allows the same muscle force to be produced, despite the larger joint range of motion.
The method described above is the most common and simplest way to measure one's vertical jump, but other more scientifically accurate methods have been devised. A pressure pad can be used to measure the time it takes for an athlete to complete a jump, and then using a kinematics equation (h = g × t2/8), the computer can calculate his or her vertical jump based on the time in the air.