Estrategia de paso y frecuencia de ciclo en piragüismo en los JJ.OO. de Pekín

The objective of this study was to analyze the performance patterns from the world�s best paddlers who took part in the Beijing Olympic Games in 2008. The pacing strategy and the evolution of the cycle frequency were analysed from the official results and films recorded from broadcast TV. The analysis database included the 12 Olympics finals (500 and 1000 m). Evolution was similar in all events. The speed decreased through out both distances. There were no differences in pacing strategy between heats or semi-finals and finals. The cycle frequency had their higher values at the beginning of the finals, remained stable in 1000 m events, and decreased along the distance in 500 m events. In conclusion, pacing strategies and cycle frequency evolution followed a negative trend in all the Olympic races, and there were no significant differences in pacing strategy between heats or semi-finals and finals.El objetivo del estudio fue analizar la estrategia de paso y frecuencia de ciclo de los mejores palistas del mundo que participaron en los Juegos Olímpicos de Pekín 2008. Se analizó la estrategia de paso y la evolución de la frecuencia de ciclo de las doce pruebas incluidas en el programa olímpico (500 y 1000 m). La evolución de las variables analizadas fue similar en todas las pruebas. La velocidad disminuyó a lo largo de ambas distancias. No se encontraron diferencias significativas en la estrategia de paso entre eliminatorias y finales. La frecuencia de ciclo obtuvo sus mayores valores al inicio de las finales, permaneciendo estable en las pruebas de 1000 m y disminuyendo en las de 500 m. En conclusión, la estrategia de paso y la evolución de la frecuencia de ciclo respondieron a un patrón decreciente en todas las pruebas, sin diferencias significativas entre pruebas clasificatorias y finales

Effects of ketosis on cocaine-induced reinstatement in male mice;

In recent years, the benefits of the ketogenic diet (KD) on different psychiatric disorders have been gaining attention, but the substance abuse field is still unexplored. Some studies have reported that palatable food can modulate the rewarding effects of cocaine, but the negative metabolic consequences rule out the recommendation of using it as a complementary treatment. Thus, the main aim of this study was to evaluate the effects of the KD on cocaine conditioned place preference (CPP) during acquisition, extinction, and reinstatement. 41 OF1 male mice were employed to assess the effects of the KD on a 10 mg/kg cocaine-induced CPP. Animals were divided into three groups: SD, KD, and KD after the Post-Conditioning test. The results revealed that, while access to the KD did not block CPP acquisition, it did significantly reduce the number of sessions required to extinguish the drug-associated memories and it blocked the priming-induced reinstatement. © 2022 The Author(s

Anthropometric and equipment characteristics in adolescent sprint kayakers

Los objetivos de este estudio fueron describir las características antropométricas y la configuración del material utilizado por 91 kayakistas españoles adolescentes de 13 y 14 años, de aguas tranquilas y buscar correlaciones entre ambas variables. Se valoraron las características antropométricas y las dimensiones del material de competición de noventa y un kayakistas de aguas tranquilas (45 hombres y 46 mujeres), de 13 y 14 años de edad. Los hombres kayakistas de 14 años presentaron valores superiores a los de 13 años en cuanto a dimensiones antropométricas y del material de competición, mientras que no se encontraron diferencias significativas entre las variables analizadas entre las mujeres kayakistas de 13 y 14 años. La talla y envergadura presentaron las mayores correlaciones con la longitud de la pala y la distancia asiento - reposapiés. La información aportada por este trabajo podría ser de utilidad para ajustar las dimensiones del material de competición, optimizando así el confort y rendimiento en kayakistas jóvenes.The aims of this study were to describe kinanthropometric characteristics and equipment set-up of male and female young kayakers and to look for correlations between both variables. Ninety one young sprint kayakers (45 males and 46 females), aged 13 and 14 years old, were assessed using a battery of 12 anthropometric and 5 equipment dimensions. Comparison between the 13- and 14-year-old kayakers showed that 14-year-old males had greater body and equipment dimensions than their 13-year-old counterparts, whereas there were no significant differences between 13- and 14-year-old female kayakers in both anthropometric and equipment set-up dimensions. Stretch stature and arm span were the variables which greater coefficient correlations showed with total paddle length and seat - feet bar distance. The data presented in this paper may provide important information to adjust equipment sep-up in order to optimise comfort and performance in young kayakers

Sagittal spinal curvatures and pelvic inclination in kayakers

El objetivo del estudio fue comparar la disposición sagital del raquis e inclinación pélvica en diferentes posiciones en kayakistas. A ciento treinta kayakistas entre 15 y 20 años (62 varones y 68 mujeres) se les evaluó, mediante un Spinal Mouse, la disposición angular del raquis torácico, lumbar e inclinación pélvica en bipedestación, sedentación relajada, máxima flexión del tronco en sedentación, test sit-and-reach, posición de base y de ataque en un kayak-ergómetro. La cifosis torácica en la piragua fue menor (p<0,001) que en bipedestación y sedentación relajada. El raquis lumbar se dispuso en inversión lumbar en las posturas de flexión del tronco y sedentación, favorecido por una posición de retroversión pélvica. Las mujeres adoptaron posturas de menor flexión lumbar y pélvica en el kayak-ergómetro. En conclusión, la posición de las mujeres en el kayak-ergómetro se caracteriza por posturas más alineadas del raquis y pelvisThe aim of this study was to compare the sagittal spinal curvatures and pelvic tilt in different positions on kayakers. One hundred and thirty kayakers between 15 and 20 years (62 males and 68 females) participated in this study. Thoracic and lumbar curvatures and pelvic position were evaluated with a Spinal Mouse system in standing position, slumped sitting, maximal trunk bending with knees flexed, sit-and-reach test, base position right entry position and left entry position in a kayak ergometer. Thoracic kyphosis in the kayak-ergometer was more reduced (p<0,001) than standing and slumped sitting. Lumbar spine adopted kyphotic postures when maximal trunk flexion was performed and in the kayak ergometer. This posture was related to posterior pelvic tilt. Females showed lower lumbar and pelvic flexion than males in the kayak ergometer. In conclusion, females adopt more aligned spinal and pelvic postures in the kayak ergometer than malesEste estudio se realizó en el marco de las ayudas de la Fundación Séneca-Agencia de Ciencia y Tecnología de la Región de Murcia (II PCTRM 2007-2010) al proyecto nº 11951/PI/09, titulado “Evolution of sagittal spinal curvatures, hamstring extensibility, low back pain, and anthropometric characteristics in elite paddlers

High integrity IMM-EKF based road vehicle navigation with low cost GPS/INS.

User requirements for the performance of GlobaL Navigation Satellite System (GNSS)-based road applications have been significantly increasing in recent years. Safety systems based on vehicle localization, electronic fee-collection systems, and traveler information services are just a few examples of interesting applications requiring onboard equipment (OBE) capable of offering a high available accurate position, even in unfriendly environments with low satellite visibility such as built-up areas or tunnels and at low cost. In addition to that, users and service providers demand from the OBEs not only accurate continuous positioning but integrity information of the reliability of this position as well. Specifically, in life-critical applications, high-integrity monitored positioning is absolutely required. This paper presents a solution based on the fusion of GNSS and inertial sensors (a Global Positioning System/Satellite-Based Augmentation System/Inertial Navigation System integrated system) running an extended Kalman filter combined with an interactive multimodel method (IMM-EKF). The solution developed in this paper supplies continuous positioning in marketable conditions and a meaningful trust level of the given solution. A set of tests performed in controlled and real scenarios proves the suitability of the proposed IMM-EKF implementation as compared with lowcost GNSS-based solutions, dead reckoning systems, single-model EKF, and other filtering approaches of the current literature.This work was supported in part by the Spanish Ministerio de Fomento under Grant FOM/3929/2005 and by the Galileo Joint Undertaking (GJU) under Grant GIROADS 332599. The Associate Editor for this paper was Y. Wang

Caracterización conductual y neuroinmune de la resiliencia al estrés social: Efectos reforzantes de la cocaína

Numerosos estudios preclínicos han demostrado que el estrés social incrementa la vulnerabilidad a los efectos reforzantes de la cocaína. Sin embargo, los resultados obtenidos no son homogéneos, observándose siempre una subpoblación que no muestra dicho incremento. Utilizando el modelo de derrota social (DS) repetida en ratones, en este trabajo hemos querido caracterizar conductualmente a los ratones resilientes al incremento de los efectos reforzantes de la cocaína inducido por el estrés social. Utilizamos ratones adultos macho de la cepa C57/BL6 a los que sometimos al protocolo de DS repetida y tres semanas más tarde, realizamos el Condicionamiento de Preferencia de Lugar (CPL) inducido por una dosis no efectiva de cocaína (1mg/kg). Una vez finalizado este procedimiento se midieron los niveles estriatales de interleucina 6, ya que el estrés social produce una respuesta de neuroinflamación. No se observó CPL en los ratones controles, pero los animales derrotados tomados en conjunto desarrollaron preferencia. Sin embargo, esta muestra se pudo dividir en ratones resilientes (no desarrollaron preferencia) y susceptibles (presentaron CPL). Durante las derrotas sociales, los animales resilientes pasaron menos tiempo en las conductas de huida y sumisión que los catalogados como susceptible y presentaron conductas de ataque hacia el ratón residente, manifestando por tanto resistencia a ser derrotados. No se observaron diferencias en la respuesta de neuroinflamación, probablemente debido al largo periodo de tiempo trascurrido desde la última derrota social. Nuestros resultados sugieren que un estilo de afrontamiento activo al estrés social va a ser determinante en la protección del sujeto a desarrollar un trastorno por uso de drogas. Preclinical studies have shown that social stress increases vulnerability to the reinforcing effects of cocaine. However, the results are not always homogeneous, revealing a subpopulation that does not show a preference for cocaine. Thus, the main aim of the present study was to characterize the behavioral profile of resilient mice to the stress-induced rewarding effects of cocaine using an animal model of repeated social defeat stress (SD). To this end, male adult mice of the C57/BL6 strain were exposed to SD and, three weeks later, assessed using the Conditioned Place Preference paradigm induced by an ineffective dose of cocaine (1mg/kg). Afterwards, the striatal levels of interleukin 6 were measured, as social stress usually induces a neuroinflammatory response. Control mice did not develop CPP, while defeated mice did overall develop a preference for the drug-paired compartment. Based on the conditioning score that they exhibited, the SD sample was subdivided into resilient (did not develop preference) and susceptible mice (developed preference). During the SD sessions, resilient animals showed less flight and submission behaviors than susceptible mice and they presented attack behaviors towards the residents, thereby showing their resistance to being defeated. There were no differences in the neuroinflammatory response, probably due to the long time elapsed after the last SD session. These results suggest that an active coping style to social stress may be decisive in protecting the individual from developing an addiction. © 2021, Edita Socidrogalcohol. All rights reserved