Swimming

Abstract

We investigated coaching points for the technique of the eggbeater kick in synchronized swimming. The movements of the eggbeater kick for six female synchronized swimmers, all the top-ranking members at the Olympics and World Championships, were analyzed by using three-dimensional motion analysis. By comparing the movements of higher eggbeater-skilled swimmers with lower eggbeater-skilled swimmers, the coaching points for techniques of the eggbeater kick in synchronized swimming are clarified as follows. First, to hold the knees as high and as near the water surface as possible and to keep the heels close to the hips. Secondly, to keep the knees as wide as possible. Thirdly, to kick sideways producing lift force, and not to kick downward. Fourthly, to pull up the heels to nearly the water surface at the out-kick, with strong internal rotation of the thighs. Lastly, to move the feet as if treading water, with strong dorsiflexion and plantar flexion and adduction of the foot; that is to move the feet like the motion of the hands when sculling. Moreover, the movements of higher eggbeater-skilled swimmers can be termed 'horizontal kick type' and the movements of lower eggbeater-skilled swimmers can be termed 'vertical kick type'.

Phthalate and Organophosphate Plasticizers in Nail Polish: Evaluation of Labels and Ingredients

“…We searched the United States Patent and Trademark Office database in March 2018 for U.S.-based patents with the abstract keywords “nail,” “polish,” and “plasticizer." The five investigated patents listed preferred total plasticizer levels as the following ranges: 0.01–25%, 50 1–5%, 51 10–30%, 52 3–20%, 53 and 0.01–25%. 54 We chose 0.01% by weight (100 μg/g), the lowest reported level, as our threshold above which concentrations could be suitable for plasticizer performance.…”

The effect of experience in movement coordination with music on polyrhythmic production: Comparison between artistic swimmers and water polo players during eggbeater kick performance

“…The results showed no statistically significant difference in the CV of natural EBK frequency between WPs and ASs, meaning that the two groups of athletes could perform EBKs in an equally stable manner when no additional tasks were involved. EBKs are a fundamental skill for both ASs and WPs [ 27 , 28 ]. Each athlete has his or her own natural, preferred EBK frequency so as to optimize their energy use and provide a stable lift force during their athletic performance [ 26 ].…”

“…It is a complex anti-phase movement that requires both legs kick at frequencies that can generate enough lift forces to keep the body above the water [ 26 ]. Homma and Homma [ 27 ] showed that ASs performed EBKs during about 40% of their total performance routines, whereas Smith found that WPs performed EBKs for more than 55% of the duration of a game [ 28 ]. ASs must perform above-water movements in synchronization with music, the tempo of which frequently changes in the course of a performance routine while maintaining their optimal EBK frequency.…”

Estimating the hydrodynamic forces during eggbeater kicking by pressure distribution analysis

“…This approach is highly reliable. However, the motion of an eggbeater kick contains a very complex combination of hip, knee and ankle motions (Homma and Homma, 2005; Oliveira et al., 2015; Sanders, 1999), which is too complicated to reproduce using a robotic leg with respect to the degree of freedom of motion. Hence, we recruited real water polo players.…”