Association between the increase in brain temperature and physical performance at different exercise intensities and protocols in a temperate environment

There is evidence that brain temperature (Tbrain) provides a more sensitive index than other core body temperatures in determining physical performance. However, no study has addressed whether the association between performance and increases in Tbrain in a temperate environment is dependent upon exercise intensity, and this was the primary aim of the present study. Adult male Wistar rats were subjected to constant exercise at three different speeds (18, 21, and 24 m/min) until the onset of volitional fatigue. Tbrain was continuously measured by a thermistor inserted through a brain guide cannula. Exercise induced a speed-dependent increase in Tbrain, with the fastest speed associated with a higher rate of Tbrain increase. Rats subjected to constant exercise had similar Tbrain values at the time of fatigue, although a pronounced individual variability was observed (38.7-41.7°C). There were negative correlations between the rate of Tbrain increase and performance for all speeds that were studied. These results indicate that performance during constant exercise is negatively associated with the increase in Tbrain, particularly with its rate of increase. We then investigated how an incremental-speed protocol affected the association between the increase in Tbrain and performance. At volitional fatigue, Tbrain was lower during incremental exercise compared with the Tbrain resulting from constant exercise (39.3±0.3 vs 40.3±0.1°C; P<0.05), and no association between the rate of Tbrain increase and performance was observed. These findings suggest that the influence of Tbrain on performance under temperate conditions is dependent on exercise protocol.

Experiences and meaning of the aquatic environment for individuals with physical disabilities

This study examines the experiences and meaning of physical activity in the aquatic environment to enhance social, cultural and political understanding of its impact in the lives of individuals with physical disabilities. Interviews, lived experience descriptions and artifacts present an explanation of the felt sense oftheir bodies as they engage in swimming or scuba diving. 11 Combining written, verbal and visual descriptions generated by informants provides a detailed account of the unique qualities of physical activity in the water for those with physical disabilities. Participants' descriptions highlight that context is an important aspect of physical activity among individuals with physical disabilities through discussion of motility and the role of the lived body. Aspects of the aquatic environment create a setting that facilitates forgetfulness of the lived body's presence. Instructors and participants alike will benefit from learning the difference between the object body and the lived body, listening to the body's voice as they participate in physical activity .

Physical geography : the global environment.

Esta publicación proporciona una base para la comprensión de los sistemas ambientales de la Tierra y sus procesos, desde el lugar que ocupa nuestro planeta en el sistema solar, a los paisajes regionales resultantes de la erosión y las fuerzas tectónicas. El texto ofrece cincuenta y dos unidades agrupadas en cinco contenidos:una perspectiva global; atmósfera e hidrosfera; biosfera; la corteza inquieta; lo que esculpió la superficie. Al final de cada unidad hay una relación de términos clave, preguntas de repaso, referencias bibliográficas y recursos web que proporcionan a los estudiantes una manera interactiva de conocer más de cerca los conceptos expuestos en texto. Tiene además un apéndice con mapa político del mundo, un apéndice con las unidades y sus conversiones, guía de pronunciación figurada, glosario e índice.

Study guide to accompany Physical Geography : the global environment.

Esta guía de estudio está diseñada para mejorar la comprensión de la geografía física. Complementa las unidades del libro de texto y las experiencias de aprendizaje. Cada unidad sigue un formato idéntico: resumen de la unidad; objetivos de la unidad; glosario de términos clave; esquema de la unidad; preguntas de examen; auto-test que se puede utilizar para preparar los exámenes de respuestas cortas. Para cada unidad hay seis preguntas de selección múltiple y verdadero o falso.

Regional differences of physical activity and sedentary behaviour in Swiss children are not explained by socio-demographics or the built environment

Objective We evaluated whether regional differences in physical activity (PA) and sedentary behaviour (SB) existed along language boundaries within Switzerland and whether potential differences would be explained by socio-demographics or environmental characteristics. Methods We combined data of 611 children aged 4 to 7 years from four regional studies. PA and SB were assessed by accelerometers. Information about the socio-demographic background was obtained by questionnaires. Objective neighbourhood attributes could be linked to home addresses. Multivariate regression models were used to test associations between PA and SB and socio-demographic characteristics and neighbourhood attributes. Results Children from the German compared to the French-speaking region were more physically active and less sedentary (by 10–15 %, p < 0.01). Although German-speaking children lived in a more favourable environment and a higher socioeconomic neighbourhood (differences p < 0.001), these characteristics did not explain the differences in PA behaviour between French and German speaking. Conclusions Factors related to the language region, which might be culturally rooted were among the strongest correlates of PA and SB among Swiss children, independent of individual, social and environmental factors.

The relationship between physical activity and perceived built environment factors among adult Mexican Americans living in Brownsville, Texas

Background. Physical Activity (PA) is a central part in the fight to reduce obesity rates that are higher in Mexican Americans in the United States than any other ethnic groups. More than half of all Americans do not meet the daily PA recommendations and 48% of Mexican Americans do not exercise. The built environment is believed to affect participation in physical activity. The influence of the built environmental on physical activity levels in low-income Mexican Americans living along the Texas-Mexico border has not been investigated. ^ Purpose. The purpose of this secondary data analysis was trifold: (1) to determine the levels of self-reported PA in adults living in Brownsville, Texas; (2) to characterize the perceptions of this population regarding the built environment; and (3) to determine the association between self-reported PA and the built environment in Mexican Americans living in Brownsville, Texas. ^ Methods. 400 participants from the Tu Salud ¡Sí Cuenta! (TSSC) community-wide campaign were included in this secondary data analysis. Percentages for level of physical activity and the built environment were calculated using SPSS. Perceptions of the built environment were assessed by 14 items. Logistic regression analysis was used to assess the relationship between physical activity and built environment. All models were adjusted for age, gender, and level of education. ^ Results. The majority of men (41.97%) and women (59%), combined (56.7%)did not meet the 2008 PA Guidelines for Americans. We analyzed 14 built environment variables to characterize participants’ perceptions of the built environment. We conducted odds ratio (OR) to find if those who met PA levels associated the built environment such as neighborhood shops ([OR:1.806], CI:1.074,3.038 ]) bus stops ([OR:1.436], CI:.806,2.558) unattended stray dogs ([OR: 1.806], CI:1. 074,3.038), sidewalk access ([OR: .858],CI:.437,1.686), access to free parks ([OR:.549],CI:.335,.900) heavy traffic in neighborhood ([OR:.802], CI:.501,1.285), crime rate ([OR:.779], CI:.494,1.228) ranked the highest by mean score. The association between physical activity and the perceived built environment factors for Mexican Americans participating in the TSSCStudy were weakly associated. ^ Conclusions. This study provides evidence that PA levels are low in this Mexican American population. The built environment factors assessed in this study characterized the need for further studies of the variables that are seen as important to the Mexican American population. Lastly, the association of PA levels to the built environment was weak overall and further studies are recommended of the built environment.^

Objective assessment of the built environment and its relationship to physical activity and obesity

The role of physical activity in the promotion of individual and population health has been well documented in research and policy publications. Significant research activities have produced compelling evidence for the support of the positive association between physical activity and improved health. Despite the knowledge about these public health benefits of physical activity, over half of US adults do not engage in physical activity at levels consistent with public health recommendations. Just as physical inactivity is of significant public health concern in the US, the prevalence of obesity (and its attendant co-morbidities) is also increasing among US adults.^ Research suggests racial and ethnic disparities relevant to physical inactivity and obesity in the US. Various studies have shown more favorable outcomes among non-Hispanic whites when compared to other minority groups as far as physical activity and obesity are concerned. The health disparity issue is especially important because Mexican-Americans who are the fastest growing segment of the US population are disproportionately affected by physical inactivity and obesity by a significant margin (when compared to non-Hispanic whites), so addressing the physical inactivity and obesity issues in this group is of significant public health concern. ^ Although the evidence for health benefits of physical activity is substantial, various research questions remain on the potential motivators for engaging in physical activity. One area of emerging interest is the potential role that the built environment may play in facilitating or inhibiting physical activity.^ In this study, based on an ongoing research project of the Department of Epidemiology at the University of Texas M. D. Anderson Cancer Center, we examined the built environment, measured objectively through the use of geographical information systems (GIS), and its association with physical activity and obesity among a cohort of Mexican- Americans living in Harris County, Texas. The overall study hypothesis was that residing in dense and highly connected neighborhoods with mixed land-use is associated with residents’ increased participation in physical activity and lowered prevalence of obesity. We completed the following specific aims: (1) to generate a land-use profile of the study area and create a “walkability index” measure for each block group within the study area; (2) to compare the level of engagement in physical activity between study participants that reside in high walkability index block groups and those from low walkability block groups; (3) to compare the prevalence of obesity between study participants that reside in high walkability index block groups and those from low walkability block groups. ^ We successfully created the walkability index as a form of objective measure of the built environment for portions of Harris County, Texas. We used a variety of spatial and non-spatial dataset to generate the so called walkability index. We are not aware of previous scholastic work of this kind (construction of walkability index) in the Houston area. Our findings from the assessment of relationships among walkability index, physical activity and obesity suggest the following, that: (1) that attempts to convert people to being walkers through health promotion activities may be much easier in high-walkability neighborhoods, and very hard in low-walkability neighborhoods. Therefore, health promotion activities to get people to be active may require supportive environment, walkable in this case, and may not succeed otherwise; and (2) Overall, among individuals with less education, those in the high walkability index areas may be less obese (extreme) than those in the low walkability area. To the extent that this association can be substantiated, we – public health practitioners, urban designers, and policy experts – we may need to start thinking about ways to “retrofit” existing urban forms to conform to more walkable neighborhoods. Also, in this population especially, there may be the need to focus special attention on those with lower educational attainment.^

Adolescents' and young adults' physical activity related to built environment

Objetivos: este trabajo tiene como objetivo analizar los niveles de actividad fisicas en estudiantes de escuelas secundarias y estudiantes universitarios; estimar su percepción del entorno contruído en relación con la actividad física, y evaluar la relación entre la educación física y el entorno contruído. Metodología: Se aplicó un estudio sociológico trasversal con diseño no experimental. Se completaron el cuestionario internacional de actividad física y el cuestionario de caraterísticas de entorno contruído con una muestra de 1.862 alumnos de escuelas secundarias y universidad en Granada, España. Resultados: los alumnos de la escuela secundaria fueron significativamente más activos que los estudiantes universitarios, quienes alcanzaron niveles insuficientes de actividad física. Sin embargo, consideraron Granada un buen contexto para hacer ejercicio al aire libre. No se encontraron relaciones entre los niveles de actividad física y el entorno contruído. Conclusión: la discrepancia de resultados entre los niveles de actividad física y la percepción del entorno contruído sugieren la necesidad de intervenciones focalizadas en hacer que los jóvenes se den cuenta de las posibilidades que el medio les ofrece para ejercitarse. En consecuencia, el medio puede tener un impacto en la salud al mismo tiempo que los jóvenes aprenden a respetarlo

Adolescents' and young adults' physical activity related to built environment

Objetivos: este trabajo tiene como objetivo analizar los niveles de actividad fisicas en estudiantes de escuelas secundarias y estudiantes universitarios; estimar su percepción del entorno contruído en relación con la actividad física, y evaluar la relación entre la educación física y el entorno contruído. Metodología: Se aplicó un estudio sociológico trasversal con diseño no experimental. Se completaron el cuestionario internacional de actividad física y el cuestionario de caraterísticas de entorno contruído con una muestra de 1.862 alumnos de escuelas secundarias y universidad en Granada, España. Resultados: los alumnos de la escuela secundaria fueron significativamente más activos que los estudiantes universitarios, quienes alcanzaron niveles insuficientes de actividad física. Sin embargo, consideraron Granada un buen contexto para hacer ejercicio al aire libre. No se encontraron relaciones entre los niveles de actividad física y el entorno contruído. Conclusión: la discrepancia de resultados entre los niveles de actividad física y la percepción del entorno contruído sugieren la necesidad de intervenciones focalizadas en hacer que los jóvenes se den cuenta de las posibilidades que el medio les ofrece para ejercitarse. En consecuencia, el medio puede tener un impacto en la salud al mismo tiempo que los jóvenes aprenden a respetarlo

Adolescents' and young adults' physical activity related to built environment

Objetivos: este trabajo tiene como objetivo analizar los niveles de actividad fisicas en estudiantes de escuelas secundarias y estudiantes universitarios; estimar su percepción del entorno contruído en relación con la actividad física, y evaluar la relación entre la educación física y el entorno contruído. Metodología: Se aplicó un estudio sociológico trasversal con diseño no experimental. Se completaron el cuestionario internacional de actividad física y el cuestionario de caraterísticas de entorno contruído con una muestra de 1.862 alumnos de escuelas secundarias y universidad en Granada, España. Resultados: los alumnos de la escuela secundaria fueron significativamente más activos que los estudiantes universitarios, quienes alcanzaron niveles insuficientes de actividad física. Sin embargo, consideraron Granada un buen contexto para hacer ejercicio al aire libre. No se encontraron relaciones entre los niveles de actividad física y el entorno contruído. Conclusión: la discrepancia de resultados entre los niveles de actividad física y la percepción del entorno contruído sugieren la necesidad de intervenciones focalizadas en hacer que los jóvenes se den cuenta de las posibilidades que el medio les ofrece para ejercitarse. En consecuencia, el medio puede tener un impacto en la salud al mismo tiempo que los jóvenes aprenden a respetarlo

(Table 1) Results of measurements of production characteristics of phytoplankton and some physical parameters of the environment in the northeastern Norwegian Sea in July 1995

From July 4 to 18,1995 surface chlorophyll a concentrations (C_cs) and integral primary production (C_ps) were studied in the northeastern part of the Norwegian Sea (73°42'N; 13°16'E), over a test area where an accident of the nuclear submarine Komsomolets had taken place. It was found that during this interval C_cs decreased by factor of about 3.3 (from 0.78 to 0.24 mg/m**3); average chlorophyll concentration within the photo-synthetic layer (C_cl) decreased by factor of about 3.5 (from 0.97 to 0.28 mg/m**3). The value of C_ps in the water column varied slightly (from 445 to 539 mg C/m**2 per day), since decrease in C_cl was compensated both by 1.5-fold growth of the photosynthetic layer thickness (from 40 to 60 m) and by 2.1-fold increase in its average assimilation number (from 0.58 to 1.20 mg C/mg chl a per hour). Monthly averages of C_ps were obtained from published data on seasonal C_cs changes and on the level of incident solar irradiation. They were found to be less than 100 mg C/m**2 per day in March and October and 100-500 mg C/m**2 per day in April-June. Annual primary production calculated from above values was equal to 105 g C/m**2.