Ali Onur Cerrah

Evaluation of the relationship between isokinetic strength and two different soccer throw-in performances

The aim of the current study was to determine ball velocity and throwing distance in standing and running throw-in techniques, and to correlate this performances with isokinetic torques of the, elbow, shoulder, and trunk extensors and flexors. 14 male amateur soccer players volunteered to participate to the current study. Concentric Isokinetic tests were measured at 60 and 180 ◦ /s angular velocities for elbow and shoulder, 30 and 120 ◦ /s angular velocities for trunk. Ball velocity was measured by a radar gun and the throwing distance was measured regarding throw-in performance. Unpaired t-test was used to analyze ball velocity and throwing distance differences between two different throwing techniques. To clarify relationship between isokinetic strength values and ball velocities and distance which occur during two types of throwing techniques Pearson Correlation Analyze was used. There were no statistical significant differences regarding throwing velocity and distance between two different throw-in tech- niques. Eventhough, theisokineticvaluesandthrowingvelocitiesdidnotcorrelatewitheachother, therewasapositivecorrelation between standing throw-in distance with elbow (non-dominant flexion at 60 and 180 ◦ s −1 ), shoulder (dominant flexion-extension at 60 and 180 ◦ s −1 , non-dominant extension at 60 and 180 ◦ s −1 ) and trunk (flexion at 30 and 120 ◦ s −1 ). The only correlation between running throw-in and throwing distance occurred in shoulder (dominant extension at 60 ◦ s −1 ) and trunk (flexion at 30 ◦ s −1 ). In conclusion, the isokinetic strength values regarding upper extremity is strong factor that describes standing throw-in performance. However; it is not highly correlated with the running throw-in performance in soccer.

The Effect of Kick Type on the Relationship between Kicking Leg Muscle Activation and Ball Velocity

This study aimed to identify the effects of different kick types on the relationship between kicking leg muscle activation and ball velocity. The muscle activation of selected knee extensor and flexor muscles of 10 amateur soccer players were measured using electromyography during the performance of six maximal soccer kick types. The highest ball velocity was achieved by the instep kick (96.2 km/hr-1), followed by the lofted kick, the inside curve kick, the outside kick, the outside curve kick, and finally the inside kick (81.3 km/hr-1). There were significant positive correlations between muscle activation and ball velocity for the vastus lateralis and lofted (0.765), inside curve (0.792) and instep kicks (0.788), and for the gastrocnemious with the outside kick (0.796). Non-significant correlations between muscle activation and ball velocity exhibited a trend such that they were positive for the vastus medialis and vastus lateralis but negative for the biceps femoris and gastrocnemious for inside-foot-dominated kicks, while this trend was reversed for outside-foot-dominated kicks. According to results, the noted trends can be explained by the change in muscle activation patterns required to orientate the foot for each type of kick; this has implications for players’ training activities.

The Relationship Between Anthropometric, Physical, Technique Components and Three Different Agility Tasks in Soccer Players

Objective: This study was aimed to investigate the relationship between anthropometric, physical, technique components and three agility tasks; planned (PAT), unplanned (UNAT) and unplanned soccer specific reactive agility test (USRAT). Eighteen sub-elite soccer players (age 18±1.28 years) attended to the this study. Material and Methods: Anthropometric measurements, linear sprint speed tests (10m static sprint, flying 20m sprint), leg muscle strength tests (depth jump, isokinetic strength test), and running technique tests (zig-zag test) were performed. Planned agility, unplanned agility and agility with one unplanned change of direction with dribbling were used to evaluate agility performances. To investigate the relationship between PAT, UNAT, USRAT and anthropometric, physical, technique components; Pearson or Spearman correlation analysis were used depending on normal distribution. Results: Static 10m sprint and PAT showed a statistically significant correlation (r=0.604). UNAT was significantly correlated to flying 20 m test (r=0.513). None of drop jumps components had significant correlations with the agility tests (p>0,05). Moreover, USRAT showed statistically significant correlation (r=-0.502), (p<0.05) with the number of steps taken at the turn movement and no significant relationship with isokinetic variables (p>0.05). Conclusion: In conclusion, if a soccer-specific task is involved in an agility test, it may be reported that the performance is most likely to be affected by player’s technical skill. Moreover, the results of running technique analysis indicate that to be better at agility task players have to be better at making decisions instead of getting closer to the ground at the turning movement.

Quantitative Analysis of Goals Scored from Set Pieces: Turkey Super League Application

Objective: The aim of our study was to investigate the effects of set-piece goals (throwin, corner, free kick and penalty) on competition results in the Turkey Super League over five seasons (2006-2007, 2007-2008, 2008-2009, 2009-2010 and 2010-2011) based on realization time (0-15, 16-30, 31-45, 46-60, 61-75 and 76-90), the status of being a home or away team, the kick area of the goals (12 penalty areas, 4 out of penalty areas) and striking technique (inside kick, inner side of instep kick, instep kick, outside kick, header and special skill). Additionally, we aim to analyze the association between the kicking area of goals and set-piece goal types, as well as between set-piece goal type and striking techniques. Material and Methods: A total of 3614 goals based on 1530 matches have been analyzed in this study. The distribution of set pieces has been investigated according to defined parameters. The frequency and percentage values of the data have been calculated using Microsoft Office Excel and chi-square test was used to calculate relations between variables. Results: The number of organized attack goals was 2594 (71.78%) and the number of setpiece goals was 1020 (28.22%) within the five seasons encompassing the 2006-2011 seasons. The highest number of set-piece goals were scored between the 76th and 90th minutes (n=221, 21.67%), from free kicks (n=404, 39.61%), from closest areas (n=606, 88.58%) and from headers (n=377, 37.06%). Conclusion: Based on our data, goals scored from set pieces have a remarkable effect on competition results; therefore, the importance of time interval, goal type, areas and kicking type of set-piece goals have been emphasized for coaches.