Figure 2. Normalised time profiles of right and left ankle lateral (Z) displacement with respect to the X axis for SC samples taken in the third 25m lap of each 100m swim (1-3: first 100m; 2-3: second 100m, 3-3: third 100m; 4.3: fourth 100m). Note that the zero line represents the midline of the body through the CM and that displacements are as if viewed from above. Positive displacement means that the ankle is to the left of the midline and negative displacement means that the ankle is to the right of the midline. Thus, the left ankle is in the upper (positive) part of the graph and the right ankle is in the lower (negative) part of the graph. Asymmetries can be assessed by comparing the displacement of right and left ankles at equivalent time points. The ankles reach their widest point, corresponding to the commencement of the kick at between 85 to 90% of the stroke cycle.