Tecnica e coordinazione della bracciata a stile libero nel nuoto

BACKGROUND: The link between asymmetries and swimming performance has been highlighted. Propulsion asymmetries may also increase injury rates. Aim of the present study was to assess upper limb asymmetries in the front crawl stroke of elite and youth competitive male and female swimmers.METHODS: Participants were 20 competitive swimmers (10 male and 10 female) of elite (G1) and youth categories (G2). The tests consisted of three 25.m freestyle trials at maximum speed with no lateral breathing. Two trials were completed with one arm only, the third one with both arms. Speed, stroke frequency, length and duration of the strokes were evaluated using video footage. Acceleration was recorded by an inertial sensor placed on the head.RESULTS: Stroke length was statistically greater and the stroke frequency lower in G1 than G2. Stroke length resulted statistically shorter in female swimmers. G1 speed resulted statistically higher and the number of strokes lower than G2. Males speed was statistically higher and the number of strokes lower than females. Speed in swimming with the dominant limb was statistically higher then with the non-dominant limb for all subjects. Accelerations measured through the inertial sensor resulted non statistically different between G1 and G2, dominant and non-dominant limb, or males and females.CONCLUSIONS: The detection of significantly different propulsions between the dominant and the non-dominant limb could indicate that the analysis of the swimming technique should take into a greater account the analysis of the symmetry of the stroke to improve both performance and well-being of the athletes.