The investigation of effects of acceleration and deceleration abilities on change of direction performance

Title of Thesis: The Investigation of Effects of Acceleration and Deceleration Abilities on Change of Direction Performance. Purpose: The purpose of the study was to investigate the effect of acceleration and deceleration and which ability is more decisive for change of direction performance. Method: The participant group consisted of Fifteen Males Regional Amateur Soccer Players (Height: 181,6±7,02 cm, Weight: 77,2 ± 7,47 kg, Age: 24,40 ± 4,94 years, Training Age: +9 years). Measurements were taken in the farthest day to the competition in season in 10m and 30m Sprint Tests, Deceleration Test, and 505 CODS test and CMJ and Drop Jump tests. The participant group's normality test was obtained with Shapiro-Wilk analysis and Pearson Correlation analysis used to investigate the relationship between values. Results: There was a significant relationship between all Speed (Sprints and Deceleration) Tests in terms of time (r value between range of 0,53/0,84, p<0,05). There was a very significant relationship between momentum values of all Speed Tests (r<0,87, p<0,01). However, there was no relationship between 505 CODS Test and 10m Sprint and Deceleration Test (r=0,18 and r=-0,20, p>0,05). There was also no relationship between Jumping Tests (CMJ and Drop Jump) and 505 CODS, Sprint, and Deceleration Tests in terms of both time and momentum (p>0,05). Conclusion: Neither acceleration nor deceleration is more decisive for better change of direction performance. This process may be more complex than hypothesized. Key Words: Braking, Momentum, Sprint, Agility, Jumping