Relationship of two vertical jumping tests to sprint andchange of direction speed in youth male soccer players

Power production is believed to provide a foundation for acceleration, maximal velocity and agility qualities. The purpose of this study was to determine the relationship of change of direction speed, acceleration, and maximal velocity to vertical jump performance in young soccer players. 77 healthy male soccer players, who regularly practice, and who play soccer in different amateur clubs in Uşak province, volunteered to this study. The participants' jumping performances (countermovement jump (CMJ) and squat jump (SJ)), speed values (10 m and 30 m), and agility values (505 agility and T-test) were determined. The relationship between parameters was evaluated through Pearson Correlations Analysis. A weak negative correlation was observed between CMJ, SJ and 505 agility test values (p= 0.00). When anaerobic power and agility performances were assessed, a weak negative correlation was found between CMJ and SJ Gmax and T-test values, while a moderate correlation was found between the 505 Agility Test (p= 0.00). There was a moderate negative correlation between the CMJ and 10-m acceleration test and 30-m maximal speed test (p= 0.00). A negative weak correlation was found between SJ and 10-m acceleration test (p= 0.01), and moderate correlation between 30-m maximal speed test (p= 0.00). When the relationship between anaerobic power and speed tests is examined, a weak negative correlation was found between CMJ Gmax and 10-m acceleration and SJ Gmax and 10-m acceleration test, respectively (p= 0.01), (p= 0.03). A moderate negative correlation was found between CMJ Gmax and SJ Gmax and 30-m maximal velocity test (p= 0.00). A significant negative moderate correlation was found between 10-m acceleration test values of the athletes and 505 Agility Test and T-test (p= 0.00). There was a negative moderate-to-strong correlation between 30-m maximal speed test values of the athletes and 505 Agility Test and T-test (p= 0.00). In conclusion, the results of this study show that muscle power can have positive effects on sprint abilities in youth amateur soccer players. Keywords: Soccer; agility; power; change of direction speed; linear speed