Whole-body vibration (WBV) is a neuromuscular training method and has been promoted as an alternative or additional strength training method. The focus of many investigations was to determine the acute impact of a bout of whole-body vibration on athletic performance and the concerning parameters. Additionally, acute exposure to WBV, has been shown to induce transient increases in strength and power (Bosco et al, 1999) and has been suggested as a mode of warming up before practice, training and competition activities of athletes (Bazett-Jones et al., 2008). The aim of this study was to investigate the acute effects of WBV on sprint running kinematics in sprint athletes. The main hypothesis was that a single session of WBV would cause neuromuscular enhancement and improvement on sprint performance. Methods: The participants were 35 sprint athletes (21.9 ± 4.3 yrs, 176.7 ± 5.1 cm, 72.3 ± 7.5 kg) (personal 100m best time: 11.00 - 11.50 s, training experience > 3 yrs). The participants were randomly assigned into the experimental (E - with vibration) and control (C - without vibration) group. Both groups performed a single session of WBV consisted of two dynamic exercises (half squat / lunge) for total duration time of 90 s (Power Plate platform - 50Hz, 2mm). Sprint performance tests were performed from both groups, before (pre) and after (post) the WBV session and measured during a 60 m sprint. The time and average velocity at distances of 10, 20, 30, 40, 50 and 60 m were obtained using the Brower timing systems (Brower, USA) where the step length and step rate of the distance interval 40-50 of each participant was recorded by a video camera (Sony-HDR SR10E) and calculated using the Peak Motus. Data were analyzed with descriptive statistics (mean, SD) and with t-test in order to examine the differences between the two groups (E & C) and between the pre-post performance tests. The significance level for the tests was set at 0.05 (p < 0.05). Results: The results showed that a single session of WBV had no effect in both E & C groups on 60m sprint performance. Despite this, time in 50 m increased significantly 0.87% (t = 2.116, p = 0.49) (pre: 6.35 ± 0.24 s, post: 6.41 ± 0.24 s) and running speed decreased significantly 0.90% (t= 2.202, p = 0.041) (pre: 7.88 ± 0.31 m/s, post: 7.81 ± 0.30 m/s) for the E group. The step length and step rate in 40 - 50m interval did not affected for the E group, instead of the decreased running speed (pre: 2.34 ± 0.22 cm - 4.01 ± 0.32 Hz, post: 2.35 ± 0.18 cm - 3.95 ± 0.32 Hz ). Discussion: The results of this study, showed that 90 s of continuous WBV produced no improvement on sprint running performance of 60m sprint, although it produced significant changes in the time (0.87%) and the running speed (-0.90%) of 50m sprint. The step length and the step rate in 40-50m interval were not affected.
© Copyright 2009 14th annual Congress of the European College of Sport Science, Oslo/Norway, June 24-27, 2009, Book of Abstracts. Veröffentlicht von The Norwegian School of Sport Sciences. Alle Rechte vorbehalten.