A three-dimensional aspect of front crawl swimming in swimmers with different proficiency levels

Problem Statement: Although three-dimensional evaluations of swimming have described aspects of a set of performance variables, studies that distinguish higher than lower swimmers' performance from a threedimensional perspective are still necessary. Approach: analyses that provide an overview regarding variables that differentiate swimmer's proficiency are required. Purpose: The aim of this study was to compare the spatiotemporal characteristics of the arm stroke between higher and lower proficiency swimmers. Methods: Twentyone swimmers (18.5 ± 3.78 years) allocated to a high and lower performance groups (G1 and G2, respectively) performed a 50m maximum front-crawl swimming, recorded by 4 underwater cameras. A cycle stroke was digitizing in specific kinematic analysis software, SIMI Reality Motion Systems. Swimming velocity, stroke rate (SR), stroke length (SL), intracycle velocity variation (IVV), stroke dimensions, hand velocity and coordination index were analyzed. Independent Student's test or Mann Whitney test (to non-parametric variables) was used to compare high and lower performance groups with p