0 computer package. All parameters were normally distributed http://www.selleckchem.com/products/17-AAG(Geldanamycin).html (Kolmogorov�CSmirnov test). The intraclass correlation coefficient (ICC) for mechanical variables was determined. Values of mechanical variables were normalized (z-score) to compare data between groups according to the Olympic category. A mixed ANOVA model was used to compare mechanical variables between execution distances in the same Olympic category; pairwise comparisons were performed using Bonferroni statistics. Cohen��s d score was quantified to analyse the effect size (Cohen, 1988). The statistical significance was set at p < 0.05. Results Table 1 sets out the statistical descriptions of all mechanical variables (TT, IF and RIF) for each group for the three EDs. The TT had an ICC R = 0.63 (95% IC, 0.42�C0.78), the IF had an ICC of R = 0.
86 (95% IC, 0.78�C0.91), and the RIF had an ICC of R = 0.77 (95% IC, 0.64�C0.86). Table 1 Comparative analysis of performance by taekwondo athletes from different Olympic weight categories according to execution distance Comparisons between groups: The mixed ANOVA model using normalized data (z-score) showed that from ED2, the heavyweight group kicked with larger IF than the featherweight group (p < 0.03); the normalized effect size d was 1.49. In addition, from ED1 and ED2, the heavyweight group kicked in a longer TT than the welterweight group (p < 0.05) and (p < 0.02), with d values of 1.13 and 1.12, respectively. Finally, from ED1, the heavyweight group kicked in a longer TT than the featherweight group (p < 0.03), and d was 1.18. No differences in RIF were found from any distance.
Comparisons within groups: For the featherweight group, the mixed ANOVA model using Bonferroni statistics adjusted for paired comparisons showed a longer TT from ED3 than ED1 and ED2, and a longer TT from ED2 than ED1 (p < 0.001); the value of d was 1.16, 1.94 and 3.33, respectively. Finally, the IF (p < 0.04) and RIF (p < 0.03) were larger in kicks made from ED1 than ED3; the d value was 0.93 and 1.01, respectively. For the welterweight group, the TT was longer from ED3 than ED1 or ED2 (p < 0.001), and longer from ED2 than ED1 (p < 0.01); the d value was 2.20, 1.69 and 0.67, respectively. For the heavyweight group, the TT was longer from ED3 than ED1 (p < 0.001) and ED2 (p < 0.03), and the d value was 2.56 and 1.85, respectively.
Finally, the IF and RIF were larger in kicks made from ED2 than from ED3 (p < 0.03); Anacetrapib the d value was 0.59 and 0.64, respectively. Discussion The purpose of this study was to analyze mechanical variables such as total response time and impact force in the roundhouse kick to the head according to the execution distance among different Olympic weight categories. To that end, a data acquisition system was adapted from Falco et al. (2009). This adapted model allowed the measurement of longer periods of kick performance (i.e., total response time) in taekwondo. This system advances in line with Heller et al.