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91.
Annie Dupuis Maheshan Indralingam Andre Chevrier Jennifer Crosbie Paul Arnold Christie L. Burton Russell Schachar 《Child development》2019,90(2):e263-e272
Adjusting speed to maintain fast and accurate performance is critical to goal-directed behavior. This study examined development of response time adjustments in the stop signal task in 13,709 individuals aged 6–17 years (49.0% Caucasian) across four trial types: correct and incorrect go, successful (stop-inhibit), and failed (stop-respond) trials. People sped more after correct than incorrect go responses and slowed more after failed than successful stop trials. Greater slowing after stop-respond but less slowing after stop-inhibit trials was associated with better response inhibition. Response time adjustments were evident in children as young as age 6, developed throughout childhood, and plateaued by age 10. Results were consistent with the predictions of the error detection and shifting goal priority hypotheses for adjustments. 相似文献
92.
Meagan M. Patterson Rebecca S. Bigler Erin Pahlke Christia Spears Brown Amy Roberson Hayes M. Chantal Ramirez Andrew Nelson 《Monographs of the Society for Research in Child Development》2019,84(3):7-185
In this monograph, we argue for the establishment of a developmental science of politics that describes, explains, and predicts the formation and change of individuals’ political knowledge, attitudes, and behavior beginning in childhood and continuing across the life course. Reflecting our goal of contributing both theoretical conceptualizations and empirical data, we have organized the monograph into two broad sections. In the first section, we outline theoretical contributions that the study of politics may make to developmental science and provide practical reasons that empirical research in the domain of politics is important (e.g., for identifying ways to improve civics education and for encouraging higher voting rates among young adults). We also review major historical approaches to the study of political development and provide an integrative theoretical framework to ground future work. Drawing on Bronfenbrenner's ecological systems model as an organizing scheme and emphasizing social justice issues, we describe how factors rooted in cultural contexts, families, and children themselves are likely to shape political development. In the second section of the monograph, we argue for the importance and utility of studying major political events, such as presidential elections, and introduce the major themes, rationales, and hypotheses for a study of U.S. children's views of the 2016 U.S. presidential election. In addition, we apply a social-justice lens to political thought and participation, addressing the role of gender/sex and race/ethnicity in children's political development broadly, and in their knowledge and views of the 2016 U.S. presidential election specifically. In interviews conducted within the month before and after the election, we examined two overarching categories of children's political attitudes: (a) knowledge, preferences, and expectations about the 2016 election, and (b) knowledge and attitudes concerning gender/sex and politics, particularly relevant for the 2016 election given Hillary Clinton's role as the first female major-party candidate for the presidency. Participants were 187 children (101 girls) between 5 and 11 years of age (M = 8.42 years, SD = 1.45 years). They were recruited from schools and youth organizations in five counties in four U.S. states (Kansas, Kentucky, Texas, and Washington) with varying voting patterns (e.g., Trump voters ranged from 27% to 71% of county voters). The sample was not a nationally representative one, but was racially diverse (35 African American, 50 Latinx, 81 White, and 21 multiracial, Asian American, Middle Eastern, or Native American children). In addition to several child characteristics (e.g., age, social dominance orientation [SDO]), we assessed several family and community characteristics (e.g., child-reported parental interest in the election and government-reported county-level voting patterns, respectively) hypothesized to predict outcome variables. Although our findings are shaped by the nature of our sample (e.g., our participants were less likely to support Trump than children in larger, nationwide samples were), they offer preliminary insights into children's political development. Overall, children in our sample were interested in and knowledgeable about the presidential election (e.g., a large majority identified the candidates correctly and reported some knowledge about their personal qualities or policy positions). They reported more information about Donald Trump's than Hillary Clinton's policies, largely accounted for by the substantial percentage of children (41%) who referred to Trump's immigration policies (e.g., building a wall between the United States and Mexico). Overall, children reported as many negative as positive personal qualities of the candidates, with negative qualities being reported more often for Trump than for Clinton (56% and 18% of children, respectively). Most children (88%) supported Clinton over Trump, a preference that did not vary by participants’ gender/sex or race/ethnicity. In their responses to an open-ended inquiry about their reactions to Trump's win, 63% of children reported negative and 18% reported positive emotions. Latinx children reacted more negatively to the election outcome than did White children. Girls’ and boys’ emotional responses to the election outcome did not differ. Children's personal interest in serving as U.S. president did not vary across gender/sex or racial/ethnic groups (overall, 42% were interested). Clinton's loss of the election did not appear to depress (or pique) girls’ interest in becoming U.S. president. With respect to the role of gender/sex in politics, many children (35%) were ignorant about women's absence from the U.S. presidency. Only a single child was able to name a historical individual who worked for women's civil rights or suffrage. Child characteristics predicted some outcome variables. For example, as expected, older children showed greater knowledge about the candidates than did younger children. Family and community characteristics also predicted some outcome variables. For example, as expected, participants were more likely to support Trump if they perceived that their parents supported him and if Trump received a greater percentage of votes in the children's county of residence. Our data suggest that civic education should be expanded and reformed. In addition to addressing societal problems requiring political solutions, civics lessons should include the histories of social groups’ political participation, including information about gender discrimination and the women's suffrage movement in U.S. political history. Providing children with environments that are rich in information related to the purpose and value of politics, and with opportunities and encouragement for political thought and action, is potentially beneficial for youth and their nations. 相似文献
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94.
Natalia Romero-Franco Juan C Fernández-Domínguez Juan A Montaño-Munuera Javier Romero-Franco Pedro Jiménez-Reyes 《Journal of sports sciences》2019,37(15):1787-1793
Muscle imbalance and deficit are key parameters for guiding rehabilitation and sports sessions and avoiding injuries. However, the high cost and non-portable nature of most instruments employed for muscle strength assessment frequently hamper an affordable evaluation in field conditions. This study evaluated the validity and reliability of a low-cost digital dynamometer to assess the maximal isometric strength of upper limb muscles. Fourteen physically active volunteers performed the main movements of the upper limb at maximal isometric strength: flexion-extension, internal-external rotation and abduction-adduction of the shoulder; and flexion-extension of both elbow and wrist. Validity was examined by comparing the strength values from the low-cost digital dynamometer and those measured by an isokinetic dynamometer, assumed as the gold standard. The correlation between both devices was perfect (r > 0.913), while Bland-Altman plots showed absolute agreement between both devices, the maximum range of the values of bias was ?0.99–1.00 N in wrist extension. Inter-tester and intra-tester reliability were excellent for all movements (ICC ≥ 0.855). The low-cost digital dynamometer showed strong validity and excellent reliability in assessing maximal isometric strength during the main movements of the upper limb. Professionals may use it for an affordable isometric muscle strength assessment in field situations. 相似文献
95.
Research remains unclear on the impact of physiological load on perceptual-cognitive skills in sport. Moreover, no study has examined the training of perceptual-cognitive skills under physiological load. The current study comprised two phases. Firstly, we examined the impact of badminton-specific physiological load on anticipatory skills in expert badminton players (n = 13), including key underlying mechanisms, such as gaze behaviour. Under high physiological load, participants displayed less efficient visual search behaviour and showed a reduction in response accuracy. Secondly, we examined the effects of combining perceptual-cognitive simulation training with the high physiological load. Ten of the expert badminton players were assigned to a combined training group, where the simulation training and the physiological load intervention occurred simultaneously or an independent training group, whereby the two components were completed independently. The combined training group showed a positive change in the efficiency of their visual search behaviours compared to the independent training group, but no significant performance improvements were found. Overall, findings demonstrate that high physiological load is detrimental to experts’ anticipatory skills. However, combining perceptual-cognitive simulation training with high physiological load can potentially negate these debilitating effects. 相似文献
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99.
Stephen J. Preece Christopher Bramah Duncan Mason 《European Journal of Sport Science》2019,19(6):784-792
The biomechanical profile of high-level endurance runners may represent a useful model that could be used for developing training programmes designed to improve running style. This study, therefore, sought to compare the biomechanical characteristics of high-performance and recreational runners. Kinematic and kinetic measurements were taken during overground running from a cohort of 14 high-performance (8 male) and 14 recreational (8 male) runners, at four speeds ranging from 3.3 to 5.6?m?s?1. Two-way ANOVA analysis was then used to explore group and speed effects and principal component analysis used to explore the interdependence of the tested variables. The data showed the high-performance runners to have a gait style characterised by an increased vertical velocity of the centre of mass and a flight time that was 11% longer than the recreational group. The high-performance group were also observed to adopt a forefoot strike pattern, to contact the ground with their foot closer to their body and to have a larger ankle moment. Importantly, although observed group differences were mostly independent of speed, the tested variables showed a high degree of interdependence suggesting an underlying unitary phenomenon. This is the first study to compare high-performance and recreational runners across a full range of kinematic and kinetic variables. The results suggest that high-performance runners maintain stride length with a prolonged aerial phase, rather than by landing with a more extended knee. These findings motivate future intervention studies that should investigate whether recreational runners could benefit from instruction to decrease shank inclination at foot contact. 相似文献
100.
Vivian Maria Arakelian Cássia da Luz Goulart Renata Gonçalves Mendes Nuno Manoel de Sousa Renata Trimer Solange Guizilini 《Journal of sports sciences》2019,37(12):1420-1428
Aim was to identify critical load (CL) in young and elderly apparently healthy male cohorts. To contrast the metabolic, cardiovascular and perceptual responses on CL according to age. We evaluated 12 young (23 ± 3 years) and 10 elderly (70 ± 2 years) apparently healthy active males, who underwent: (1) 1 repetition maximum (1RM) test on a 45° Leg Press; (2) on different days, three high-intensity resistance exercise constant load tests (60%, 75% and 90% 1RM) until fatigue (Tlim). Absolute values of both the CL asymptote and curvature constant (kg) were significantly lower in elderly subjects (P < 0.05). In contrast, elderly subjects demonstrated a significantly higher number of repetitions at CL when compared with young subjects (P < 0.05). As expected, oxygen uptake (VO2) and heart rate (HR) during maximal aerobic exercise testing were significantly reduced in older subjects. However, percent-predicted aerobic capacity were higher in older subjects (P < 0.05). In addition, blood lactate ([La?]) corrected to Tlim and rating of perceived exertion values were greater in younger subjects at all intensities (P < 0.05). These findings, despite reduced force production in older subjects, endurance-related parameters are well preserved according to age-adjusted percent-predicted values in apparently healthy males. 相似文献