177 research outputs found
THE KICK START: KEY OF ITS SUPERIORITY
The purposed of this study was to observe the differences between the grab start and the kick start regarding the initial position that determines the aspect that the swimmers must train to improve their start. Results showed some advantages in the times obtained by the kick start in the block phase, keeping them until the hands entry. The kick start was able to reach a similar entry distance, similar than the grab start can do, at 0.18 s less with a small difference in the horizontal velocity in the flight. The rear foot allows the swimmers to reach an acceleration peak of 11.81 ± 2.05 m/s² in 0.37 ± 0.05 s while in the grab start the values were lower and the increase of the acceleration more progressive (8.97 ± 1.02 m/s² in 0.67 ± 0.08 s). With the kick start the swimmers were able to produce a great horizontal force since the moment of the starting signal
Impacto del tratamiento periodontal básico en los niveles de porphyronomas gingivalis y Aggregatibacter actinomycetemcomitans a nivel local y su relación con la enfermedad cardiovascular: Estudio piloto a 6 meses
Ante la presencia de evidencia científica suficiente que apoya la asociación de las enfermedades cardiovasculares y las enfermedades periodontales, y las dificultades existentes a la hora de realizar estudios de intervención que permitan evaluar los beneficios del tratamiento periodontal en la enfermedad cardiovascular, se propone el siguiente ensayo clínico de 6 meses de duración con pacientes con antecedentes de síndrome coronario agudo ocurrido hace menos de un año y con periodontitis crónica moderada-avanzada, donde el grupo test recibe tratamiento periodontal básico en 2 días consecutivos junto con enjuagues con clorhexidina durante diez días, mientras el grupo control recibe una profilaxis dental acompañado de enjuagues con flúor durante diez días
Entrenamiento técnico y biomecánico en Natación: El modelo del Centro de Alto Rendimiento de Sierra Nevada
Desde el comienzo de su actividad, La Unidad de Análisis del Rendimiento Deportivo (UARD) del C.A.R. de Sierra Nevada ha desarrollado protocolos de análisis técnico y de control del entrenamiento que han sido utilizados por nadadores y entrenadores durante sus estancias en el centro. Algunos de los trabajos realizados en este departamento, son: Test de 50 m + Viraje (Arellano, Pardillo & García, 1999), Desarrollo de bases de datos de errores técnicos para la corrección del nado, la salida o los virajes, Pruebas de análisis de la velocidad intraciclo, Análisis tridimensional de la fuerza y la trayectoria de la brazada, etc. La elección de uno u otro test se consensua con los entrenadores en función de la prontitud con la que requieran los resultados, eligiendo métodos que requieren procesamiento de los datos tras la realización de los test o bien sesiones de entrenamiento específico en las que existe aportación de feedback inmediato tras cada ensayo. En cualquier caso, se gestionan y entregan los resultados a través de bases de datos que permiten comparar la evolución de los nadadores a lo largo de sus estancias en el centro o bien comparar la ejecución con otros nadadores de la misma especialidad
A SYSTEM TO IMPROVE THE SWIMMING START TECHNIQUE USING FORCE RECORDING, TIMING AND KINEMATIC ANALYSES
The purpose of our study was to develop a system to improve the swimmer’s starting technique integrating force and video data. A group of elite swimmers (n=17) took part in the study. Cinematic and kinetic variables of the start technique during the block, flight, and swimming phases until the end of the first 10 m were analysed. The horizontal velocity during the take-off (3,96 m/s) and peak horizontal force applied (917,2 N) did not correlate with the 5 m time (1,79 s). Only the value of the velocity vector before the moment of the hand entry (4,63 m/s) correlated with the 5 m time (r=-0.56). The transformation of the velocity components of the swimmer’s centre of mass during the flight to a high horizontal gliding speed seems the more complex problem for the swimmer to resolve and where our future research will be directed
A SYSTEM TO IMPROVE THE SWIMMING START TECHNIQUE USING FORCE RECORDING, TIMING AND KINEMATIC ANALYSES
The purpose of our study was to develop a system to improve the swimmer’s starting technique integrating force and video data. A group of elite swimmers (n=17) took part in the study. Cinematic and kinetic variables of the start technique during the block, flight, and swimming phases until the end of the first 10 m were analysed. The horizontal velocity during the take-off (3,96 m/s) and peak horizontal force applied (917,2 N) did not correlate with the 5 m time (1,79 s). Only the value of the velocity vector before the moment of the hand entry (4,63 m/s) correlated with the 5 m time (r=-0.56). The transformation of the velocity components of the swimmer’s centre of mass during the flight to a high horizontal gliding speed seems the more complex problem for the swimmer to resolve and where our future research will be directed
COMPARISON OF THE SWIMMING START PERFORMANCE BETWEEN INDIVIDUAL AND RELAY FREESTYLE RACES
The aim of the present study was to compare the swimming start performances between individual and relay events in freestyle races. Competitors who took part in both the individual 100m freestyle and the 4×100m freestyle relay races during the LEN 2017 European Junior Championships were analysed in the present study. The results indicated that swimmers performed 6.92% faster 15m start time in relay race versus the individual freestyle race and the difference seemed to be due to the longer reaction time from the race beginning. Coaches and swimmers would be suggested to try to optimize their relay starting performance in order to take more benefit on flight, underwater and swimming phases compare to individual start
FIRST SECTION OF THE COURSE PERFORMANCE AS A CRITICAL ASPECT IN SKICROSS COMPETITION: 2010 OLYMPIC GAMES & WORLD CUP ANALYSIS
Skicross (SX) is a winter sports discipline that consists of racing across an uneven track with jumps, banked turns and other obstacles. The 56 heats of the 2010 most important competitions were studied: Vancouver Olympic Winter Games (OWG) and Sierra Nevada World Cup Final (WCF). In both races we analyzed the skiers rank at each heat’s first turn as well as their final rank at the finish. A great percentage of riders that were ahead
at the first turn of the race, classified in the top two positions and reached the next round: OWG, (87,5%) ♂ and ♀; WCF, ♂ (81,25%) and ♀ (87,5% ). These results suggest that a
fast first section of the course can contribute to race success. Specific start training becomes necessary to compete at SX high level
RELATIVE FORCE AND PAP IN SWIMMING START PERFORMANCE
Firstly, it was studied the relationship between relative force (Frel) of the lower limbs in a isotonic Lunge test, with the performance in a swimming kick start (SS). Afterwards, were applied two Postactivation-Potentiation (PAP) specific warm ups in order to analyze their effect in performance considering the Frel of the subjects. Trained swimmers (n=14) volunteered in this study. Pearson product-moment correlation coefficients were used to verify the relationship between relative force and kinematic variables of a SS. Results revealed high correlation between relative force and performance in SS (Dive Distance: R2=0.872,
Effect of an activation protocol based on postactivation potentiation on swimming start performance
Introduction: There is a potentiation method called Postactivation Potentiation (PAP) which is based on the application of near maximal loads, conducted prior to the exercise performance, which improves the ballistic movement (Tillin & Bishop, 2009). The purpose of this study was to compare the effect of an activation protocol on swimming start performance (SS).
Methods: Fourteen trained volunteer swimmers participated in the study. An intra-group design of randomized repetitive measurements was applied. A previous standard SS trial after a standard warm up served as reference (P1). One method of activation was applied: Four repetitions in the flywheel YoYo Squat (P2). Kinematic variable of SS were collected using video analysis
Results: After P2, the subjects achieved a higher mean horizontal velocity during the flight (VxH) (4.89 ± 0.12 m/s) than after P1 (3.63 ± 0.11 m/s) (p < 0.001). After P2, it took the subjects less time to cover a distance of five meters (T5m) (1.65 ± 0.052 sec) compared to P1 (1.75 ± 0.057 sec) (p ≤ 0.001)
Discussion: The use of the flywheel device was based on two clear objectives: taking advantage of the high lower limb activation which provokes potentiation; and the possibility to execute an activation gesture almost identical to the real action. The results obtained in this study are clear evidence that an improvement of the peak forces occurred on the block as was observed by Breed and Young (2003). We observed that VxH ostensibly improved, which means that the swimmer’s flight was longer and faster. T5m also showed to be shorter after P2 application, suggesting that take-off potentiation provokes that swimmer enter into the water with more velocity. These results suggest that a warm up based on the PAP by repetitions on the flywheel improves the SS.CTS-527: Actividad física y deportiva en el medio acuátic
Explotación del aroma potencial de frutas autóctonas aragonesas mediante evaluación químico-sensorial
El sabor de las manzanas (gusto y aroma) es una característica distintiva de esta fruta y su aroma está asociado a moléculas volátiles odorantes y a precursores del aroma. Al someter estos precursores a un tratamiento de hidrólisis ácida, se consiguen romper los enlaces glicosídicos, permitiendo la liberación de las agliconas volátiles y, por tanto, consiguiendo más aroma. En este trabajo se estudian los tiempos óptimos de hidrólisis y los perfiles de aroma potencial de 10 variedades de manzanas, tanto comerciales (Esperiega, Galaxy y Golden Smothe), como autóctonas aragonesas (MA-056, MA-109, MA-178, MA-184, MA-230, MA-263, MA-296). Este estudio revela que existen precursores del aroma en la pulpa de manzana. Asimismo, se pueden observar diferencias en el perfil del aroma potencial de las manzanas autóctonas y comerciales. Todas las variedades comerciales destacan por los atributos “especiado” y “fruta compotada”, en cambio, las variedades autóctonas destacan por diferentes atributos, lo cual demuestra la diversidad aromática de estas variedades de manzana y podría suponer una revalorización tecnológica de su pulpa. Se ha observado como las variedades MA-056 y MA-178 destacan por tener mayor intensidad en el atributo “fruta compotada”, la variedad MA-263 en el atributo “fruta blanca” y las variedades MA-184 y MA-230 en el atributo “miel”.<br /
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