AbstractThis report aims (1) to examine the association between seasonality and physical activity (PA) and sedentary time in European adolescents and (2) to investigate whether this association was influenced by geographical location (Central-North versus South of Europe), which implies more or less extreme weather and daylight hours. Valid data on PA, sedentary time and seasonality were obtained in 2173 adolescents (1175 females; 12.5–17.5 years) included in this study. Physical activity and sedentary time were measured by accelerometers. ANCOVA was conducted to analyse the differences in PA and sedentary time across seasons. Results showed that girls had lower levels of moderate to vigorous PA (MVPA) and average PA, and spent more time in sedentary activities in winter compared with spring (all P < 0.05). Stratified analyses showed differences in PA and sedentary time between winter and spring in European girls from Central-North of Europe (P < 0.05 for sedentary time). There were no differences between PA and sedentary time across seasonality in boys. In conclusion, winter is related with less time spent in MVPA, lower average PA and higher time spent in sedentary activities in European adolescent girls, compared with spring. These differences seem to mainly occur in Central-North Europe. 相似文献
AbstractTriathlon is a popular outdoor endurance sport performed under a variety of environmental conditions. The aim of this study was to assess physiological variables before and after a half-ironman triathlon in the heat and to analyse their relationship with performance. Thirty-four well-trained triathletes completed a half-ironman triathlon in a mean dry temperature of 29 ± 3ºC. Before and within 1 min after the end of the race, body mass, core temperature, maximal jump height and venous blood samples were obtained. Mean race time was 315 ± 40 min, with swimming (11 ± 1%), cycling (49 ± 2%) and running (40 ± 3%) representing different amounts of the total race time. At the end of the competition, body mass changed by ?3.8 ± 1.6% and the change in body mass correlated positively with race time (r = 0.64; P < 0.001). Core temperature increased from 37.5 ± 0.6ºC to 38.8 ± 0.7ºC (P < 0.001) and post-race core temperature correlated negatively with race time (r = ?0.47; P = 0.007). Race time correlated positively with the decrease in jump height (r = 0.38; P = 0.043), post-race serum creatine kinase (r = 0.55; P = 0.001) and myoglobin concentrations (r = 0.39; P = 0.022). In a half-ironman triathlon in the heat, greater reductions in body mass and higher post-competition core temperatures were present in faster triathletes. In contrast, slower triathletes presented higher levels of muscle damage and decreased muscle performance. 相似文献
ABSTRACTThis study assessed the intra-individual reliability of oxygen saturation in intercostal muscles (SmO2-m.intercostales) during an incremental maximal treadmill exercise by using portable NIRS devices in a test-retest study. Fifteen marathon runners (age, 24.9 ± 2.0 years; body mass index, 21.6 ± 2.3 kg·m?2; V?O2-peak, 63.7 ± 5.9 mL·kg?1·min?1) were tested on two separate days, with a 7-day interval between the two measurements. Oxygen consumption (V?O2) was assessed using the breath-by-breath method during the V?O2-test, while SmO2 was determined using a portable commercial device, based in the near-infrared spectroscopy (NIRS) principle. The minute ventilation (VE), respiratory rate (RR), and tidal volume (Vt) were also monitored during the cardiopulmonary exercise test. For the SmO2-m.intercostales, the intraclass correlation coefficient (ICC) at rest, first (VT1) and second ventilatory (VT2) thresholds, and maximal stages were 0.90, 0.84, 0.92, and 0.93, respectively; the confidence intervals ranged from ?10.8% – +9.5% to ?15.3% – +12.5%. The reliability was good at low intensity (rest and VT1) and excellent at high intensity (VT2 and max). The Spearman correlation test revealed (p ≤ 0.001) an inverse association of SmO2-m.intercostales with V?O2 (ρ = ?0.64), VE (ρ = ?0.73), RR (ρ = ?0.70), and Vt (ρ = ?0.63). The relationship with the ventilatory variables showed that increased breathing effort during exercise could be registered adequately using a NIRS portable device. 相似文献
The contribution of universities to society is due to the effects generated both in the supply and in the demand side, the latter being associated with the injection of demand as a result of the activities these institutions carry out. This paper focuses on the impact of the demand side by designing a methodology based on Monte Carlo simulations so as to introduce stochastic elements in calculating the economic impact of universities. We apply this methodology to the case of Valencian public universities, introducing stochastic elements in all the elements which imply assumptions with uncertainty. The results highlight the importance of considering uncertainty by generating multipliers which can vary around the average value by 18 % in the case of output and employment, and 10 % in the case of income. 相似文献
ResumenSe aborda en este trabajo la dominancia o lateralización hemisférica cerebral, en cuanto posible factor etiológico de interés para la neuropsicología de la dislexia evolutiva. Se precisan las relaciones con la lateralidad manual y se revisan, a la luz de los conocimientos actuales, los conceptos legados por Broca y Orton. En este sentido, también se revisa la teoría de la dominancia desde el principio (Kinsbourne) en cuanto contrapuesta a la teoría de la progresiva lateralización hemisférica en la ontogenia (Lenneberg). Los principales modelos de dislexia basados en la organización cerebral se agrupan según hagan referencia a la integración interhemisférica, a la especialización hemisférica o a la integración intersensorial. Como aplicación a la educación, se proponen algunas consideraciones generales derivadas del enfoque neuropsicológico y se revisa críticamente el carácter generalizador de una educación basada en la hemisfericidad. 相似文献
Executive functions (EF) are a set of processes that allow individuals to plan, monitor and organize tasks and thus play a key role in the development of reading and maths skills. Environmental factors such as socioeconomic level (SEL) influence reading and maths skills as well as EFs. The aim of this study is to explore the extent to which executive functions play a mediating role between SEL and reading and maths performance. To this end, we assessed 286 Chilean primary education students: 86 with a high SEL and 200 with a low level. The results show that the high-SEL group obtained consistently higher scores than their peers with low SEL levels in both reading and maths tasks as well as in EF measurements. This suggests that SEL could influence the development of these variables. The results also showed that EFs partially mediate the relation between SEL and reading and maths skills in primary school students through the specific function of inhibition. The results are discussed in light of the effect of SEL on the development of EFs and school learning. 相似文献
Cognates are words that are the same or nearly the same orthographically and semantically in English and Spanish. The majority of the more than 20,000 cognates are academic vocabulary words comprised of Latin and Greek roots and affixes. Several thousand cognates can be found in the picture books that have earned the Américas Book Award, which was established to honor quality multicultural books that portray Latino cultures in a positive light. The authors present lessons for teaching primary school Latino ELLs about cognates through the Américas Award picture books, as they educate their students about their rich Latino cultures. 相似文献
This study investigated relationships between career adaptability and personality and pathological traits using the network analysis approach. We administered CAAS, BFI-2-S, and IDCP-2 to 630 working adults. We observed positive associations between personality and career adaptability and negative associations between pathological traits and career adaptability. This paper contributes to the understanding of the associations between career adaptability and Big Five personality traits and pathological traits. We found stronger associations between career adaptability and personality traits as compared to pathological traits. Our findings suggest that Neuroticism and Conscientiousness contribute more to adaptation to professional development tasks than do pathological traits.