The effects of vibration on explosive and reactive strength when applying individualized vibration frequencies

Abstract

The aim of this study was to assess the effects of 8 weeks of whole-body vibrations on explosive and reactive leg strength. Thirty-three physically active students took part in the study and were randomly assigned to an individualized-vibration group, a fixed-vibration group or a control group. The frequency of vibration was set to 30 Hz for the fixed-vibration group, whereas the frequency for the individualized-vibration group was determined by monitoring the participants' EMGrms activity. The participants in the two vibration groups were exposed three times a week for 8 weeks to a series of 10 x 1-min whole-body vibrations with a 1-min pause between series of vibrations and a 4-min pause after the first five series of vibrations. Jump height in the squat jump increased significantly in all three groups (by 11% for the individualized-vibration group, p=0.001; by 3% for the fixed-vibration group, p=0.011; and by 2% for the control group, p=0.006), but countermovement jump height was not affected. In continuous rebound jumps by the individualized-vibration group, jumping height increased by 22% (p=0.006) and power increased by 18% (p=0.002). The results of this study suggest that the use of an individualized vibration frequency produces a greater response from the neuromuscular system and is more beneficial than vibrations at a fixed pre-selected frequency.

The Effect of Whole-Body Vibration on Jump Height and Active Range of Movement in Female Dancers

“…The study also demonstrates that significant improvements can be achieved in relatively shorter periods of time (4 weeks) with less exposure to WBV than reported in earlier studies (4,6,7,13,15,26,28,33). The mechanisms responsible for physiological adaptation are much debated; however the present 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 study appears to favour neurological adaptation as the dominant mechanism even in trained subjects.…”

“…Previous research (4,6,7,13,15,26,28,33) often used sedentary subjects where it is to be expected that performance adaptations occur without circumferential changes in muscles due to the primarily muscular adaptation to overload being neuromuscular. The present study using trained subjects still noted an improvement in jump performance without hypertrophical development suggesting the WBV can still cause neuromuscular adaptations, as suggested by Bosco et al (7,8).…”

“…Overall it appears the literature demonstrates a positive effect of WBV on jumping performance with several short term cumulative effect studies (10 days-8 weeks) have noted improvements in jump height (4,6,7,13,15,26,33) whilst a few have noted no improvements (11,12,23). In relation to dance training the studies by Wyon and colleagues (33) and Aninno and colleagues (4) both noted increases in jump height as well as no significant changes in leg anthropometry and significant increases in knee extensor strength respectively.…”

Optimal whole-body vibration settings for muscle strength and power enhancement in human knee extensors

“…More recently, Colson et al (2010) observed that a 4-week WBV training program could increase SJ height, although no sham training group was included in their study. In addition, Di Giminiani et al (2009) reported no significant difference in SJ improvement between WBV and sham groups after an 8-week training period. Therefore, the present investigation is the first to report greater increases in SJ height after WBV training compared with sham training.…”

Changes in postural sway frequency and complexity in altered sensory environments following whole body vibrations

“…Additional vibration parameters that will likely impact the effectiveness of WBV is the overall duration of the exposure and the recent finding suggesting that each individual may have a particular frequency to which their muscles respond most vigorously (Di Giminiani, Tihanyi, Safar, & Scrimaglio, 2009). This individualized frequency may help to alleviate the equivocality of past studies and more clearly define the vibration parameters that effect the greatest change on motor control.…”