Starting out, athletes should always err on the conservative side and only perform 10-20 maximal effort jumps in a training session. Because of the explosive nature of a vertical jump, the body can only perform a handful before performance starts to drop. Training beyond this point will not improve jumping height and will only lead to injury. At the completion of a training session, it is generally recommended to rest 48 hours before completing another intense training session.
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.