Vertical jump
A vertical jump or vertical leap is the act of raising one's center of mass higher in the vertical plane solely with the use of one's own muscles; it is a measure of how high an individual or athlete can elevate off the ground (jump) from a standstill.
Types
The vertical jump is divided into two different types:
- Standing Vertical Jump: This refers to a vertical jump done from a standstill with no steps being involved at all.[1]
- Running vertical jump: This refers to a vertical jump after an approach or run to help add energy to the jump in an effort to improve on the standing vertical jump
In general, the standing vertical jump is the one that is used as an official measurement for athletes.
Where vertical jump measurements are used
Vertical jump measurements are used primarily in athletic circles to measure performance. The most common sports in which one's vertical jump is measured are track and field, netball, basketball, football, and volleyball, but many sports measure their players' vertical jumping ability during physical examinations. In addition, single and multiple vertical jumps are occasionally used to assess muscular strength and anaerobic power in athletes
Measurement
The simplest method to measure an athlete's vertical jump is to get the athlete to reach up against a flat wall, with a flat surface under his/her feet (such as a gym floor or concrete) and record the highest point he/she can reach flat-footed (this is referred to as "standing reach"); fingertips powdered with chalk can facilitate the determination of points touched on the wall. The athlete then makes an effort to jump as high as possible (usually from a standstill) and touch the wall at the apex of the jump; the athlete can perform these jumps as many times as needed. The highest point the athlete touches is recorded. Next, the distance between these two recorded points is measured. This distance is the athlete's standing vertical jump.
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),[4] the computer can calculate his or her vertical jump based on the time in the air.
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.
Maximization
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.[5]In order to maximize vertical jump height an athlete must be willing apply and develop the specific jump training principles of strength, power and reactiveness. Correctly prescribed and programmed vertical jump training protocols will optimize both the force producing and elastic properties of the musculotendinous system within the lower limbs.
Vertical jump and power output
Vertical jumps are used to both train and test for power output in athletes. Plyometrics are particularly effective in training for power output, and include vertical jumps of different types in their protocol. In one recent study, training with plyometrics (which included continuous vertical jumps) was shown to incresse vertical jump performance to similar degrees in combination with very different resistance training protocols, indicating that the plyometric jumping contributed to the increased jump height more than resistance training. Research into plyometric jumps found vertical jumps to be among the highest in terms of muscle recruitment (as measured by electromyography), power output, and ground reaction force produced. Fatigue has been researched in athletes for its effect on vertical jump performance, and found to decrease it in basketball players, tennis players, cyclists, rugby players, and healthy adults of both genders.
Standing vertical jump norms
This is the vertical jump test scores by gender.
Rating | Males (cm) | Males (in) | Females (cm) | Females (in) |
---|---|---|---|---|
Excellent | >70 | >28 | >60 | >24 |
Very good | 61–70 | 24-28 | 51–60 | 20-24 |
Above average | 51-60 | 20-23 | 41-50 | 16-19 |
Average | 41-50 | 16-19 | 31-40 | 12-15 |
Below average | 31-40 | 12-15 | 21-30 | 8-11 |
Poor | 21-30 | 8-11 | 11-20 | 4-7 |
Very poor | <21 | <8 | <11 | <4 |
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