Pinto Mafalda P, Marinho Daniel A, Neiva Henrique P, Barbosa Tiago M, Morais Jorge E
Department of Sport Sciences, University of Beira Interior, 6201-001 Covilhã, Portugal.
Research Centre in Sports, Health and Human Development (CIDESD), 6201-001 Covilhã, Portugal.
J Funct Morphol Kinesiol. 2024 Jul 25;9(3):129. doi: 10.3390/jfmk9030129.
The aim of this study was to compare swimming speed and speed fluctuations in front crawl between swimmers of different performance levels using discrete variables against statistical parametric mapping (SPM). The sample was composed of 34 male swimmers divided into three groups: (i) group #1-recreational swimmers; (ii) group #2-competitive swimmers aged 12 to 14 years; (iii) group #3-competitive swimmers aged 15 to 17 years. Swimming speed and speed fluctuations (calculated based on four different conditions) were used as discrete variables. Using these discrete variables, ANOVA one-way was used to verify differences between groups, and Bonferroni post-hoc correction for pairwise comparison whenever suitable. SPM (with similar statistical tests) was used to analyze the swimming speed and fluctuation as a continuous variable. Overall, both statistical approaches revealed significant differences ( < 0.001) in swimming speed and speed fluctuations. However, as discrete variables (in four different conditions), the speed fluctuation was not able to detect significant differences between groups #2 and #3. Conversely, SPM was more sensitive and did yield significant differences between these two groups. Therefore, researchers and coaches should be aware that the speed fluctuation as a discrete variable may not identify differences in swimming speed fluctuations when the average value between groups is marginal. On the other hand, SPM was more sensitive in analyzing all groups.
本研究的目的是使用离散变量并结合统计参数映射（SPM），比较不同水平的游泳运动员在自由泳时的游泳速度和速度波动。样本由34名男性游泳运动员组成，分为三组：（i）第1组——业余游泳者；（ii）第2组——年龄在12至14岁的竞技游泳者；（iii）第3组——年龄在15至17岁的竞技游泳者。游泳速度和速度波动（基于四种不同条件计算得出）被用作离散变量。使用这些离散变量，采用单向方差分析来验证组间差异，并在合适时使用Bonferroni事后检验进行两两比较。SPM（采用类似的统计检验）用于将游泳速度和波动作为连续变量进行分析。总体而言，两种统计方法均显示出游泳速度和速度波动存在显著差异（<0.001）。然而，作为离散变量（在四种不同条件下），速度波动未能检测出第2组和第3组之间的显著差异。相反，SPM更为敏感，确实在这两组之间产生了显著差异。因此，研究人员和教练应意识到，当组间平均值接近时，作为离散变量的速度波动可能无法识别游泳速度波动的差异。另一方面，SPM在分析所有组时更为敏感。
