As players did not have any history of formal plyometrics, all exercises were supervised and particular attention was paid to demonstration and execution, giving maximal motivation to athletes during each jump. Although we did not increase the training volume during the 7-weeks period, as we used high-intensity plyometric exercises performed with maximal effort, an effective and safe training stimulus was applied during each plyometric session, as previously demonstrated in similar plyometric training interventions in young boys (Ramírez-Campillo et al., 2012) and soccer players (Ramírez-Campillo et al., 2014b; Thomas et al., 2009). The exercise were completed 2 times per week, for a total of 7 weeks.