The NV Racks Non-Varying Resistance is designed to allow athletes to generate their max power output at a light repeatable weight. With jumping athletes are already generating their max power output when jumping, or they should be. This article gives a great breakdown of the science behind a vertical jump. However just practicing jumping over and over again as high as you can is not the most effective way to increase your power. That is where the NV Rack comes into play. Using the power of Non-Varying Resistance along with the French Contrast Method, the NV Rack takes your training program to a whole other level.