A second, more efficient and correct method is to use an infrared laser placed at ground level. When an athlete jumps and breaks the plane of the laser with his/her hand, the height at which this occurs is measured. Devices based on United States Patent 5031903, "A vertical jump testing device comprising a plurality of vertically arranged measuring elements each pivotally mounted..." are also common. These devices are used at the highest levels of collegiate and professional performance testing. They are composed of several (roughly 70) 14-inch prongs placed 0.5 inches apart vertically. An athlete will then leap vertically (no running start or step) and make contact with the retractable prongs to mark their leaping ability. This device is used each year at the NFL scouting combine.
“There’s something about dunking a basketball that lures us in,” he said, reflecting on his first jam, during lunch period his sophomore year at De La Salle High in Concord, Calif., back when his driver’s license read 5' 11", 112 pounds. “It stokes the imagination. It’s something you always dream of doing. I have a friend whose father, at age 50, is trying to dunk.”
Shocks work and the ride is much better but installing them is a pain. They don't come compressed and are hard to compress by hand. For a 2012 F250 I bolted the lower portion of the shock up then took a racket strap and hooked it around the top bolt collar. Racket it till its close to the hole then release the strap and knock it over in the hole. That was the way I did it. The first side took forever trying to muscle it in then I busted out the strap and had it on in 5min.........Good product but I wish it would have came compressed.
Scaling the back squat for beginner-level athletes generally entails sticking to lighter loads (even bodyweight only to start) while learning proper technique. Goblet squats with a kettlebell or dumbbell can be used to practice form, but keep in mind that goblets are an anterior (front-loaded) variation and won’t directly mimic the mechanics of the back squat.
An important component of maximizing height in a vertical jump is attributed to the use of counter-movements of the legs and arm swings prior to take off, as both of these actions have been shown to significantly increase the body’s center of mass rise. The counter-movement of the legs, a quick bend of the knees which lowers the center of mass prior to springing upwards, has been shown to improve jump height by 12% compared to jumping without the counter-movement. This is attributed to the stretch shortening cycle of the leg muscles enabling the muscles to create more contractile energy. Furthermore, jump height can be increased another 10% by executing arm swings during the take off phase of the jump compared to if no arm swings are utilized. This involves lowering the arms distally and posteriorly during the leg counter-movements, and powerfully thrusting the arms up and over the head as the leg extension phase begins. As the arms complete the swinging movement they pull up on the lower body causing the lower musculature to contract more rapidly, hence aiding in greater jump height. Despite these increases due to technical adjustments, it appears as if optimizing both the force producing and elastic properties of the musculotendinous system in the lower limbs is largely determined by genetics and partially mutable through resistance exercise training.