Motivos y hábitos de práctica de actividad física en escolares de 12 a 16 años en una población rural de Sevilla

La creciente preocupación en nuestro país por los problemas que conllevan la obesidad y el sedentarismo plantea de forma imperiosa detectar las carencias en la actividad física de la población escolar. En este sentido nuestro estudio ahonda un poco más en los motivos y hábitos de práctica de niños y niñas entre 12 y 16 años de una zona rural de Sevilla. Los resultados muestran como tan solo un 28% de las chicas practica actividad física (AF) con asiduidad. Estos porcentajes no son tan preocupantes en el caso de los chicos (58%). Otro aspecto determinante en este trabajo ha sido el establecer los motivos que llevan a los alumnos a practicar AF, siendo la diversión el motivo fundamental en chicos y chicas (38% y 31% respectivamente). Similares motivos encuentran diversos autores (García Ferrando, 1997; Palou et al., 2005; Chillón, 2005). Por otra parte ¿la falta de tiempo¿ es el principal motivo que argumentan los alumnos para no practicar AF (24% de los chicos y 28% de las chicas), siendo éste el más determinante igualmente en otros trabajos (García Ferrando, 1997; Hernán et al., 2002; Palou et al., 2005). Teniendo en cuenta los motivos y prácticas aquí reflejados, padres y educadores debemos promover estrategias atractivas que reviertan positivamente en el ocio de nuestros niños, facilitando así los tan codiciados "hábitos saludables"

Incidencia del ejercicio físico y el entrenamiento vibratorio sobre la amplitud de movimiento de mujeres con fibromialgia

ResumenObjetivoEn la presente investigación hemos planteado como objetivos principales, por un lado, valorar el efecto del ejercicio físico y el entrenamiento vibratorio sobre la amplitud de movimiento en mujeres con fibromialgia (FM) y, por otro, determinar si existe alguna relación entre dicha variable y el dolor y la rigidez.MétodoLa muestra estuvo constituida por un total de cuarenta y seis mujeres (edad: 58,2±8,5 años; peso: 72,1±9,6kg; altura: 156,9±6,1cm) diagnosticadas con FM. Los participantes fueron divididos aleatoriamente en tres grupos: ejercicio físico y entrenamiento vibratorio (WBV + EJ; n=15); ejercicio físico sin vibraciones (EJ; n=15) y un grupo control (GC; n=16). Los grupos WBV + EJ y EJ realizaron dos sesiones semanales de ejercicio físico durante 8 semanas. Además, los integrantes de WBV + EJ realizaron 3 sesiones semanales de entrenamiento vibratorio (30Hz, 4mm). Las pruebas de evaluación incluyeron el test de sit and reach (variable principal), la valoración del número de tender points (TP) y una escala analógica visual (VAS) para determinar la rigidez.ResultadosLos resultados derivados del análisis intra e intergrupo no mostraron diferencias significativas en la rigidez o el número de TP, si bien, la prueba de sit and reach mostró una mejora estadísticamente significativa en WBV + EJ (58%; p<0,05). El análisis correlacional mostró una relación inversa (r =-0,55; p<0,05) entre el sit and reach y el número de TP.ConclusiónComo conclusión, podemos indicar que los datos obtenidos en la presente investigación han mostrado los efectos significativos del entrenamiento vibratorio sobre la amplitud de movimiento en mujeres con FM, aunque el número de TP o la rigidez no se vieron afectados en ningún caso.AbstractObjectiveThe main aim of this investigation was twofold: first to evaluate the effects of exercise and whole body vibration training on flexibility in women with fibromyalgia (FM) and determine whether these improvements are related to symptom severity (stiffness and bodily pain).MethodForty-six women (mean±sd, age: 58.2±8.5 years; weight: 72.1±9.6kg; height: 156.9±6.1cm) with FM were randomized into one of three groups: exercise and whole body vibration (WBV) training group (WBV + EX; n=15), exercise training group (EX), and usual-care control group (CG). WBV + EX and EX groups carried out two sessions per week of exercise training for 8 weeks. In addition, WBV + EX group performed 3 vibration-training (30Hz, 4mm) sessions per week. Outcome assessed included sit and reach test (primary outcome), tender points (TP) evaluation, and a visual analog scale (VAS) was used to determine the stiffness level.ResultsResults showed no statistical intra and intergroup differences in stiffness or the number of TP. However, a significant increment in the sit and reach performance was observed in WBV + EX (58%; p<0.05). Moreover, correlation analysis showed an inverse and significant relationship (r=-0.55; p<0.05) between sit and reach and number of TP in WBV+EX group.ConclusionIn conclusion, exercise and WBV seems to be effective on flexibility in women with FM. However, the number of TP and stiffness was not modified after the interventio

Effects of gluteal kinesio-taping on performance with respect to fatigue in rugby players

Kinesio-tape® has been suggested to increase blood circulation and lymph flow and might influence the muscle's ability to maintain strength during fatigue. Therefore, the aim of this study was to investigate the influence of gluteal Kinesio-tape® on lower limb muscle strength in non-fatigued and fatigued conditions. A total of 10 male rugby union players performed 20-m sprint and vertical jump tests before and after a rugby-specific fatigue protocol. The 20-m sprint time was collected using light gates (SMARTSPEED). A 9-camera motion analysis system (VICON, 100 Hz) and a force plate (Kistler, 1000 Hz) measured the kinematics and kinetics during a counter movement jump and drop-jump. The effect of tape and fatigue on jump height, maximal vertical ground reaction force, reactivity strength index as well as lower limb joint work were analysed via a two-way analysis of variance. The fatigue protocol resulted in significantly decreased performance of sprint time, jump heights and alterations in joint work. No statistical differences were found between the taped and un-taped conditions in non-fatigued and fatigued situation as well as in the interaction with fatigue. Therefore, taping the gluteal muscle does not influence the leg explosive strength after fatiguing in healthy rugby players

Design of a Radiant Heat Capturing Device for Steel Mills

This paper approaches the energy transition towards decarbonization and lower primary energy use in the steel and glass industries through the exploitation of radiant waste heat. In contrast with exhaust gases heat recovery, radiant waste heat has typically not been used. This energy waste is found in energy intensive processes in which high temperatures are reached. For instance, in the steel making process, the cast steel is red hot and emits a considerable amount of radiant energy. In this paper the conceptual design of a radiant heat capturing device is presented. This device enables the recovery of currently unused energy while solving the radiative emission-related problems. The achieved design gets to an optimized solution regarding view factors and optical properties of the involved surfaces. In this research work, those factors are optimized to maximize the amount of heat recovered by the presented device. Simulation tools are used to test different designs and define the most appropriate solution for a given case.This work has been performed under BEROA-GO project (Waste Heat Collection from Solids for Efficient and Competitive Use), granted by the Basque Government (Spain), exp. KK-2017/00060

Different strategies to achieve Pb-tolerance by the two Trebouxia algae coexisting in the lichen Ramalina farinacea

Lichen thalli are permeable to airborne substances, including heavy metals, which are harmful to cell metabolism. Ramalina farinacea shows a moderate tolerance to Pb. This lichen comprises two Trebouxia phycobionts, provisionally referred to as TR1 and TR9, with distinct physiological responses to acute oxidative stress. Thus, there is a more severe decay in photosynthesis and photosynthetic pigments in TR1 than in TR9. Similarly, under oxidative stress, antioxidant enzymes and HSP70 protein decrease in TR1 but increase in TR9. Since Pb toxicity is associated with increased ROS formation, we hypothesized greater Pb tolerance in this phycobiont. Accordingly, the aim of the present study was to characterize the physiological differences in the responses of TR1 and TR9 to Pb exposure. Liquid cultures of isolated phycobionts were incubated for 7 days in the presence of Pb(NO3)2. Thereafter, extracellular and intracellular Pb accumulation, photosynthetic pigments, and photosynthesis (as modulated chlorophyll fluorescence) were analyzed along with the antioxidant enzymes glutathione reductase (GR), superoxide dismutase (SOD), ascorbate peroxidase (APx), and catalase (CAT), and the stress-related protein HSP70. Pb uptake increased with the amount of supplied Pb in both algae. However, while significantly more metal was immobilized extracellularly by TR9, the amount of intracellular Pb accumulation was three times higher in TR1. In neither of the phycobionts were significant effects on photosynthetic pigments or photosynthetic electron transport observed. While under control conditions GR, SOD, and APx levels were significantly higher in TR1 than in TR9, only in the latter were these enzymes induced by Pb. This resulted in quantitatively similar antioxidant activities in the two algae when exposed to Pb. In conclusion, the phycobionts of R. farinacea make use of two different strategies against stress, in which the integration of distinct anatomical and physiological features affords similar levels of Pb tolerance.This study was supported by the Spanish Ministry of Science and Innovation (CGL2009-13429-C02-01/02) and the Generalitat Valenciana (PROMETEO 174/2008 and GVACOMP2011-205). We are grateful to the Central Support Service in Experimental Research (SCSIE), University of Valencia (Spain), for the TEM studies. We acknowledge Dr. Said Agouram (SCSIE, University of Valencia, Spain) for TEM-EDXS characterizations and for helpful discussions during the TEM investigations. We thank Wendy Ran and Daniel Sheerin for the English revision of the manuscript.Álvarez, R.; Del Hoyo, A.; García Breijo, FJ.; Reig Armiñana, J.; Del Campo, EM.; Guéra, A.; Barreno, E.... (2012). Different strategies to achieve Pb-tolerance by the two Trebouxia algae coexisting in the lichen Ramalina farinacea. Journal of Plant Physiology. 169(18):1797-1806. https://doi.org/10.1016/j.jplph.2012.07.005S179718061691