After that, to analyse the data collected the VirtualDub 1.8.8 software by Avery Lee was used. To obtain boat velocity information, the frame in which the bow of the kayak/canoe was aligned with the buoys was selected. These buoys indicated the beginning and the end of the sections analyzed. Then, the difference between the initial and final frame of each stage was calculated. selleck compound The time taken to cover the section was calculated by dividing this number by 30. Finally, boat velocity (m/s) was obtained dividing 50 m by the time taken to cover the section. Cycle frequency (cycles/s) was calculated by counting the complete cycles performed in the section. In this case, the frames when the blade tip first contacted the water were selected. These frames were always higher or equal to the number of frames used to calculate the velocity.

After that, the difference between the initial and the final frame was divided by 30. Then, the number of complete cycles was divided by this number. There were two additional circumstances taken into account in this analysis: 1) the first cycle of each race was excluded because the boat started from a static position, so this cycle was different to the rest; 2) to calculate the last cycle frequency, the frame when the blade tip last contacted the water surface before the finish line was used. The cycle length (m/cycle) of each section was calculated by dividing the kayak velocity between the cycle frequency obtained in a certain section. To calculate the cycle index (m2/(cycles?s)) the boat velocity was multiplied by the cycle length obtained in each section.

Analyses Data were analysed using the Statistical Package for Social Sciences (SPSS Inc, version 15.0, Chicago, ILL, USA) via repeated measures ANOVA and post hoc Bonferroni tests. Reliability and within-subject variability for mean and peak responses were assessed using intraclass correlation coefficients (ICC) and measures bias/ratio with associated 95% limits of agreement (LOA), respectively. Data are presented as mean �� SD with alpha set at 0.05. Results Boat velocity values for the four sections are shown in Table 1. What is worth mentioning is that boat velocity evolution was similar for all paddlers with a first section slower and a second section faster than the others. After that, the velocity decreased significantly (p<0.

05) in the two final sections, except in the last section of the men canoe test. There Cilengitide were significant differences (p<0.05) in men and women kayakers in the first section when compared with the others and among all groups comparing the second section with the 100 to 150 m section. Comparisons between the groups demonstrated significant differences in velocity (p<0.01) because men kayakers were the fastest in all sections. In addition, significant differences (p<0.01) were found between women kayakers and men canoeists in the 50 to 100 m and in the 100 to 150 m sections.