Objetives. To compare the responses produced after concentric and eccentric training of the lower limbs in the anaerobic power of the lower train measured by performing vertical jumps. Methods. The methodology used was based on the protocol of Bosco, by means of which we evaluated the muscular power through vertical jumps (SJ, CMJ, DJ) realized in a platform of contact. The subjects were divided into three different groups: a control group (G1), an experimental group performing an eccentric work of knee flexors (G2) and an experimental group performing a concentric work on knee extensors (G3). Results. Significant differences were obtained in favor of G3 with respect to G1 in all variables except in power in the three types of jump and in contact time and stiffness in DJ (p≤0.05). It was also revealed that there was no significant difference between G3 and G2; However, all values obtained by G3 were higher than in G2, except in the power produced in DJ that was slightly higher in this group (p> 0.05). Disscusion. Significant differences were achieved in favor of G3, so we can deduce that a pre-jumping, concentric work on the knee extensor muscle produces significant improvements in the anaerobic power of the lower train. However, G2 also revealed some positive differences with respect to the control group. Conclusions. It follows that the performance of an eccentric exercise that is not of the knee extensors causes an activation of the central nervous system, producing an over-activation and greater recruitment of motor neurons in the lower train, causing an improvement in the anaerobic power of the lower train.