To date, a number of studies have reported that countermovement jump (CMJ) is enhanced following acute VbX in elite field-hockey players (Cochrane and Stannard, 2005), trained recreational athletes (Bedient et al. 2009, Cormie et al. 2006, Bosco et al. 2000) although one study has reported no effect in elite athletes (Bullock et al., 2008).