The correct torque ratio between the knee joint extensor and flexor muscle groups can effectively prevent injuries to the anterior cruciate ligament and hamstring strain. However, it is unclear whether a high torque ratio of the knee joint flexor muscles to the extensor muscles is beneficial for sport performance. Therefore, the aim of the study was to investigate the relationship between the hamstring-to-quadriceps (H/Q) ratio and sprint times (10- and 30-m) and jump heights (CMJ—countermovement jump and SJ—squat jump) in soccer players. The study examined 26 young elite soccer players (age: 18.1 ± 0.7 years; body height: 1.77 ± 0.05 m; body mass: 72.7 ± 5.7 kg). Knee joint flexor and extensor peak torques were assessed using the Cybex dynamometer (at 60°/s, 120°/s and 180°/s). Additionally, each participant performed the CMJ, SJ, and 30 m sprint. A significant relationship was obtained between the H/Q ratio (60°/s) and 30 m sprint time (r = 0.47). The positive direction of this relationship may indicate an important role of knee joint extensors in sprinting performance. Moreover, the H/Q ratio was not significantly associated with the CMJ, SJ or 10 m sprint performance. The H/Q ratio should be considered together with the peak torque values in terms of the assessment of sprinting and jumping performance.

The objective of the present study was to investigate the selected performance adaptations of amateur soccer players to 2 different running-based sprint interval training (SIT) protocols with different recovery intervals and work-rest ratios (1:5 & 1:1). Twenty-three subjects (age 21.4±1.1...

Background and Study Aim. Sprint performance plays a major role in success of field-based team sports such as soccer. The aim of this study was to evaluate the relationship between sprinting performance and both lower and upper extremity explosive strength in young soccer players. Material and Methods. One hundred forty-seven soccer players (mean±SD; age 11.6±1.66 years, height 143.2±11.8 cm, body mass 37.1±10.2 kg and training experience 1.11±1.5 years) voluntarily participated in this study. The sprinting performance of each player was determined using their 5, 10, 20 and 30m single sprint times. The lower and upper extremity explosive strength were evaluated by standing long jump and medicine ball throwing tests respectively. Prior to the study, each of the players was given detailed information about the risks and injuries they could encounter during the study, and parental consent was obtained by their signatures on informed voluntary consent forms since the subjects were under the age of 18. Permission to conduct the study was obtained from Ankara University Medical Faculty’s Surgical and Medical Research Ethics Committee. Results. The results indicated a strong relationship between sprinting performance and horizontal jump performance (r=-.671 ̶ -.764; p=0.001) and also a large relationship between sprinting performance and upper extremity strength (r=-.633 ̶ -.703; p=0.001). The sprint performance (n=147) also significantly correlated with body weight (r=-.345 ̶ -.373; p=0.001) and height (r=-.445 ̶ -.505; p=0.001). Conclusions. The study results suggest that upper extremity strength is as important as the lower extremity strength for sprinting performance and that trainers should emphasize lower and upper extremity strength in training intended to improve sprinting performance.

In this study, we aimed to compare ACTN3 rs1815739, PPARA rs4253778 and IL-6 rs1800795 polymorphisms with aerobic endurance in volleyball players. Twenty-two volleyball players (age: 21.59 ± 2.70 years; height: 1.87 ± 7.92 m; body weight: 80.99 ± 8.14 kg; body fat: 12.05 ± 5.78%) participated in the study voluntarily. DNA extraction from buccal epithelial cells was provided by a commercial kit. Real-Time PCR was performed for genotyping. Statistical analysis of the test results was performed using SPSS 23 (SPSS Inc., Chicago, IL, USA) package program. Homogeneity of variance was analyzed by Levenne test and normal distribution was analyzed by Shapiro-Wilk test. One Way ANOVA Test was used to analyze all parameters. Significance was determined at p0.05). In the findings, no statistically significant difference was detected between the relevant polymorphisms and aerobic performance parameters in our cohort. In conclusion, ACTN3 rs1815739, PPARA rs4253778 and IL6 rs1800795 genes did not create any difference in aerobic endurance in volleyball players. Our results need to be confirmed by further studies.