Abstract

The object of this present work is to evaluate the influence of the football pre-seasons indifferent ways in the explosive force and velocity of players, both professional and amateur. In consequence, before and after the pre-season different methods of the vertical jump and a speed race between 38 football players of the same club -20 professionals and 18 amateurs were measured. The two teams improved their results and the professional group more so in the vertical jumps, although no differences were found between either group at the beginning and end of the pre-season. Therefore, the improvements of all players in general were significant in VO-20 and VO-50 (pointing out that the VO-50 is better thanks to VO-20) as in all the vertical jump methods, being “few” compared with the results of other studies. In conclusion, the lack of difference between professional and amateur players combined with the tiny increases in the heights of the jump indicates a deficit in the introduction and planning of the explosive force work. Similarly, it stands out that the protocols more sensitive to training have been ABK, RJ15 and VO-20, and less sensitive SJ, DJ40, VO-50 and Vmax