Emre Ak

Coincidence-Anticipation Timing and Reaction Time in Youth Tennis and Table Tennis Players:

The purpose of this study was to compare the coincidence-anticipation timing and reaction times (RT) of 10- to 14-year-old tennis and table tennis players and examine possible sex differences. 107 (51.4%) tennis and 101 (48.6%) table tennis players participated in this study. Players were compared on coincidence-anticipation timing and reaction time. Tennis players performed with less error in the coincidence-anticipation timing task than table tennis players, whereas table tennis players had lower mean reaction time than tennis players. It was also found that male players made fewer errors in the coincidence-anticipation timing task than their female counterparts.

Serum cartilage oligomeric matrix protein accumulation decreases significantly after 12 weeks of running but not swimming and cycling training - A randomised controlled trial

BACKGROUND Acute effects of physical exercise on the deformational behaviour of articular cartilage and changes in cartilage oligomeric matrix protein (COMP) are definite. However, conclusive positive effects of fitness exercise on functional adaptation of articular cartilage have not been proved. AIM Therefore, in this parallel-group randomised controlled trial, we tested the hypothesis that adequate amount of physical exercise with enough impact would be able to stimulate the functional behaviour of articular cartilage. METHODS We evaluated 44 healthy males for their physical-fitness levels and their blood samples were obtained before, immediately after and 0.5h after a 30-min walking exercise. Thereafter, participants were assigned to the running, the cycling, the swimming and the control groups. At the end of 12weeks of intervention, the same measurement procedures were applied. Mixed repeated-measures analysis of variance (ANOVA) design was used for statistics. ( LEVEL OF EVIDENCE 2). RESULTS Pre-test measurements showed that 30min of walking significantly increased serum-COMP levels in all groups. The post-tests revealed that the COMP level of all groups, except running, showed an increase after a 30-min walking activity. CONCLUSION Overall, it was concluded that, 12weeks of regular, weight-bearing, high-impact physical exercise (i.e., running) decreases the deformational effect of walking activity. This finding is an evidence of functional adaptation of articular cartilage to specific environmental requirements.

The Effect of Fatigue on the Kinematics of Free Throw Shooting in Basketball

The Effect of Fatigue on the Kinematics of Free Throw Shooting in Basketball Fatigue is an indispensible part of a basketball game which may affect an athletes shooting kinematics. Although kinematic analyses of various sports related movements were extensively done, this study is the first to consider the effects of fatigue on the kinematics of free throw shooting. After measuring the resting heart rate, ten collegiate level, male basketball players (21.8±1.6 y; 192.8±3.6 cm; 84.1±8.5 kg) were asked to perform free throws. Two successful and two unsuccessful free throws were selected. Thereafter, participants were asked to complete the fatigue protocol, which included 30m sprints and 5 vertical jumps at each end, until they reached volitional exhaustion. Additional two successful and two unsuccessful free throws were collected. All shots were recorded by using two digital cameras operating at 60 Hz and placed in a stereoscopic view. The elbow, trunk, knee and ankle joint angles were measured before and after the ball release and at the ball release point. The selected joint angles were compared between successful and unsuccessful free throws, as well as before and after the completion of fatigue protocol. The results demonstrated that fatigue did not effect free throw shooting kinematics (p>0.05) and there was no significant joint angle difference between successful and unsuccessful shots (p>0.05). This study suggested that high level athletes are able to cope with the possible detrimental effects of fatigue while performing coordinated movements such as free throw shooting.

The effects of eccentric hamstring training on lower extremity strength and landing kinetics in recreational female athletes

Hamstring training involving eccentric loading is an important protective factor in hamstring injuries. However, the effect of this mode of training on lower extremity loading in landing maneuver performance is unknown. The purpose of this study was to examine variations in eccentric hamstring strength after 10-weeks training program and the possible changes in landing kinetics. Twenty five recreational female athletes were voluntarily assigned to the Nordic Hamstraing Strength Training (N = 13) or control groups (N = 12). The training group performed 10-weeks eccentric hamstring strength training program. Baseline measures of landing kinetics were collected using a force plate while strength data was evaluated using an isokinetic dynamometer. Results indicated that NHST group increased their eccentric hamstring strength (pre = 2.34 ± 0.28, post = 2.57 ± 0.25 Nm/kgbw; p < 0.05) after training program albeit without changes in the dynamic control ratio. There were also significant decreases in peak anterior-posterior ground reaction force (PAPGRF; pre = 1.14 ± 0.21 BW, post = 0.85 ± 0.27 BW; p < 0.05) and peak vertical ground reaction force (PVGRF; pre = 6.27 ± 1.00 BW, post = 5.34 ± 1.01 BW; p < 0.05) scores for NHST group. The present study supports the positive effect of eccentric hamstring strength in altering landing kinetics in order to decrease the applied forces.