Acute Effects of High- vs. Low-frequency Vibration Foam Rolling

Flexibility will be assessed with the sit-and-reach test using an adjustable sit-and-reach bench (Adjustable Sit-and-Reach Flexibility Tester, Lafayette Instrument Company, Lafayette IN, USA). The sit-and-reach test is a valid and reliable method used to assess flexibility in many studies. First, the sit-and-reach bench placed on the mat will be fixed to the wall, and the players will be asked to place the soles of their feet on the sit-reach bench with their knees completely straight on the mat. Then, after one trial, players will be asked to reach forward as far as possible three times without bending their knees, and the average of the three assessments will be used for analysis.

Dynamic balance will be assessed with the Y balance test. Before the assessment, the players will be performed three trials each with 30-second rest intervals for the dominant extremity, and after the trials, the players will be given a five-minute recovery period. During the assessment after the recovery process, to ensure standardization, the players will be asked to position their dominant extremity at the centre of the junction of the measuring tapes, lie on the measuring tape with their non-dominant extremity, extending as far as possible in the anterior, posterolateral, and posteromedial directions, and touch the furthest point they could reach with their toes. This procedure will be performed by players three times with 30-second rest intervals. The greater reach distance for each direction will be calculated with the formula [(reaching distance/lower extremity length) x 100 = percentage of the maximum reaching distance)], and will be normalised with the extremity length.

Vertical jump will be assessed with the Performanz JumpR, a valid and reliable device for assessing different jump performances.This device measures jump height based on the individual's flight time using the equation (jump height= 980.6653(flight time/1000.0)2/8). It also calculates anaerobic power using the individual's weight, flight time, and contact time using the equation (anaerobic power=weight x [9.813(flight time/2000,000)/(contact time/1000)]). For each jump, subjects will be instructed to jump as high as possible and keep their hands on their hips. There will be 1 minute of rest between jumps. All athletes will be received instructions to maximize their jump height and were verbally encouraged to exert maximum effort during all jump trials. The average of the three assessments will be used for analysis.