, 2004), strength (Kokkonen et al., 1998; Fowles et al., 2000) nor VJ performance (Young and Behm, 2003; Wallmann et al., 2005). Effects of SS on muscular force production capabilities are still a controversial topic. Many studies indicate that SS may decrease muscle strength (Fowles ARQ197 chemical structure et al., 2000) and explosive power (Young and Elliott, 2001; Bradley et al., 2007) but other research does not support a negative influence of SS applied before exercise (Power et al., 2004; Manoel et al., 2008). We expected to find a negative effect of SS on VJ performance because of a possible inhibitory effect on the Golgi tendon organ. However, our four minute application of SS did not result in a negative effect on VJ.
The lack of an inhibitory effect might possibly be explained by differences in the pain threshold levels of subjects which may have resulted in inadequate execution of the stretching exercises. Subjects were asked to perform the stretch movement until they experienced pain and then to hold the stretch for 30 seconds in this position. Since pain thresholds and flexibility levels differ from person to person, variations in the execution of SS may have prevented tendon inhibition. In the final stage of this study, the combined effects of direct vibration and SS execution were investigated. Some researchers have found a negative effect of combined static stretching and vibration (Herda et al., 2009), but the combined vibration with SS application did not yield negative effects in the present study. Vibration (50 Hz, 1.0�C2.
0 mm displacement) was directly applied to the Achilles tendon during the 30 second SS and no significant change was found in the VJ performance after this application (p>0,05). Kinser et al. (2008) investigated the effects of simultaneous vibration and static stretching on flexibility and explosive power in 22 young female competitive gymnasts. They applied direct vibration (30Hz, 2mm displacement) at four sites combined with 10 second SS and allowed 5 seconds of rest between sets. They showed that acute vibration�Cstretching resulted in significantly different increment levels in flexibility (p<0.05) compared with vibration-only treatments. Explosive power variables such as peak force, rate of force development, jump-height, flight time and instantaneous forces over the jump were not statistically different in pre/post jump performance in either the counter movement jump or squat jump (p>0.
05). There was no significant change in power parameters of jump performances after the application of 30 Hz-vibration frequency (10sec �� 4 Dacomitinib sets) combined with SS (Kinser et al., 2008). We expected to observe a positive effect on jump performance and EMG parameters after a one set application of 50 Hz-vibration lasting 30 seconds, but no such effect was found in jump performance or EMG parameters (p>0.05). Herda et al. (2009) examined the acute effects of passive stretching vs.