variations: The vertical jump test can also be performed using a specialized apparatus called the Vertec. The procedure when using the Vertec is very similar to as described above. Jump height can also be measured using a jump mat which measures the displacement of the hips. To be accurate, you must ensure the feet land back on the mat with legs nearly fully extended. Vertical jump height can also be measured using a timing mat. The vertical jump test is usually performed with a counter movement, where there is bending of the knees immediately prior to the jump. The test can also be performed as a squat jump, starting from the position of knees being bent. Other test variations are to perform the test with no arm movement (one hand on hip, the other raised above the head) to isolate the leg muscles and reduce the effect of variations in coordination of the arm movements. The test can also be performed off one leg, with a step into the jump, or with a run-up off two feet or one foot, depending on the relevance to the sport involved. For more details see vertical jump technique.
To build strength in the legs that will be compatible with the speed developed through successful plyometrics drills, squat and lunge exercises are important components. Squats are performed with free weights, where the athlete uses a weighted bar to carry out the exercise. The additional weight will be supported by the body through the abdominal, lumbar (low back), and gluteal muscles, in addition to the legs. This form of exercise permits the strengthening of the legs in conjunction with enhancing the core strength of the body, essential to the balance necessary to have the several muscle groups involved in leaping work in harmony.
Resident Evil 2: DualShock Ver., known as Biohazard 2 DualShock Ver. (バイオハザード2：デュアルショックバージョン Baiohazādo Tsū: De~yuarushokkubājon?) in Japan, As the title suggests, is a second expanded version of Resident Evil 2 that became the base of other subsequent versions/ports of the game. The game was modified to incorporate support for the vibration function and analog control of the PlayStation DualShock controller.