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931.
This study investigated the effects on neuromuscular performance of a 6-week Optimal Load Training (OLT) and a novel modified Complex Training (MCT) (complex pairs: the same exercise using a moderate and an OL) in basketball players, in-season. Eighteen male athletes were randomly assigned to one of the protocols. Anthropometric measurements were taken to evaluate body composition. Lower- and upper-body maximum dynamic strength, countermovement jump (CMJ), standing long jump (SLJ), 10-m sprint and change of direction (COD) were also assessed. Moderate-to-large strength gains (presented as percentage change ± 90% confidence limits) were obtained for half-squat (OLT: 10.8 ± 5.3%; MCT: 17.2 ± 11.6%) and hip thrust (OLT: 23.5 ± 17.7%; MCT: 28.2 ± 19.0%). OLT athletes achieved likely small improvements in sprint (1.6 ± 1.6%) and COD (3.0 ± 3.2%). Players in the MCT attained likely moderate improvements in COD (3.0 ± 2.0%) and possibly small in SLJ (2.5 ± 4.6%). No protocol relevantly affected CMJ or body composition. An ANCOVA test revealed unclear between-group differences. In conclusion, both protocols increased basketball players’ strength without the use of heavy loads (> 85% 1RM) and without impairing sprint, CMJ and SLJ performance. These findings suggest that basketball strength and conditioning professionals may use either method to counteract strength losses during the season.  相似文献   
932.
933.
The coincidence-anticipation timing (CAT) task assesses one facet of cognitive and motor performance and is used to understand the human visuo-motor system involved in intercepting the moving object. To assess the test–retest reliability and the concurrent validity in the Bridge Games package (Bridge) developed to assess the CAT task, the scores of 224 healthy subjects (M = 52.2, SD = 19.5 years old) were measured using the Bridge and the ‘gold standard’ Bassin Anticipation Timer (Bassin). A mean block of absolute, constant, and variable errors was calculated. Reliability and validity were expressed using intraclass correlation coefficients (ICC2,k), standard error of measurement, minimal detectable change, and Pearson’s correlation. Reliability was good to excellent for all blocks (.73 ≤ ICC ≤ .88), and the validity was good to excellent when compared using Pearson’s correlation coefficient, suggesting that the two tests may have similar properties. Bridge is an alternative to existing clinical tests for the CAT task.  相似文献   
934.
Background: We aimed to evaluate the influence of the level of effort during four basic resistance exercises leading to muscular failure on intraocular pressure (IOP) and ocular perfusion (OPP), as well as the role of exercise type and sex. Methods: Twenty-five young adults (12 women) performed 10 repetitions against their 10-RM (repetition maximum) load in the squat, military press, biceps curl and calf raise exercises. IOP was measured before, during and after exercise, whereas OPP was indirectly assessed before and after each exercise. Results: There was a progressive IOP rise during exercise (p?η²?=?0.531), which was dependent on exercise type (p?=?0.020, η²?=?0.125). The squat exercise induced higher IOP increments in comparison to the other exercises (corrected p-values?p-values?=?0.012 and 0.002). OPP exhibited a significant reduction when leading to muscular failure (p?=?0.001, η²?=?0.364), being statistically significant for the squat and military press exercises (corrected p-values?=?0.037 and 0.047). No effect of sex was found for IOP and OPP (p?>?0.05). Conclusions: A single set of resistance training leading to muscular failure causes an instantaneous and progressive IOP rise in healthy young individuals. These IOP rises depend on exercise type (squat?>?military press?=?biceps curl?>?calf raise), but not on participant´s sex. OPP diminished as a consequence of performing resistance training exercise, being statistically significant for the squat and military press exercises. Future studies should include glaucoma patients aiming to corroborate the generalizability of our findings.  相似文献   
935.
The elimination of spray paint using traditional (chemical and mechanical) methods inevitably entails altering surface characteristics. Hence, the impact and deterioration caused by graffiti in heritage buildings and monuments have led to the development and application of preventive systems in the form of antigraffiti coatings (which prevent paint from seeping into the pores of the surface material and facilitate cleaning). The effectiveness of two of these treatments, a commercial product (fluoroalkyl siloxane, protectosil, marketed by Degussa) and a hybrid organic-inorganic material (Ormosil), was evaluated in five construction materials (limestone, granite, cement mortar, lime mortar and brick), in terms of their penetration into the substrate. A number of techniques were used to determine the penetration depth (SEM/EDX, micro-Raman and LIBS), because a comparative analysis showed that none was universally valid for all types of treatments. The results show that the presence of the coating on the surface of less porous materials only ensures effective cleaning when the surface is fairly smooth. In granite, for instance, the CF3 terminals in the fluorinated treatment hinder spray paint bonding more effectively than Ormosil, but not efficiently enough to ensure complete removal of the paint from granite surfaces.  相似文献   
936.
Objectives: This study’s aims were to describe the development of physical activity, physical fitness (PF), subjective (physical complaints (PC)) and objective (Body mass index (BMI)) health measures and to examine the relationship between the development trajectories. In addition, the study also aimed to assess the influence of sociodemographic determinants (age, sex, socioeconomic status (SES)) in German adults over a period of 18 years. Methods: The longitudinal study population comprises of 721 men and women, aged 33–76 years over the study period. There was self-report of physical activity and PC and testing of physical fitness and BMI in each study year (1992, 1997, 2002 and 2010). Latent growth curve models were used to analyse the development. Results: Physical activity slightly increased while fitness, PC and BMI worsened over the course of 18 years. Sex, age and SES play important roles concerning physical activity, fitness and health. Several integrative associations could be detected between physical activity, fitness, PC and BMI as well as their trajectories. In particular, high initial levels of physical activity and fitness protect from high PC and BMI.The slope of physical activity was not significantly associated with slopes of fitness, PC and BMI. However, increase of fitness resulted in decrease of PC. Conclusions: A general positive development regarding the amount of physical activity could be detected. However, if it is only an unsystematic increase of physical activity, this is not in itself enough to achieve health benefits. The strengthening of fitness should be focused when increasing physical activity, since only then a health benefit is possible.  相似文献   
937.
This study aimed to evaluate the relationship between objectively measured total sedentary time and academic achievement (AA) in Portuguese children. The sample comprised of 213 children (51.6% girls) aged 9.46 ± 0.43 years, from the north of Portugal. Sedentary time was measured with accelerometry, and AA was assessed using the Portuguese Language and Mathematics National Exams results. Multilevel linear regression models were fitted to assess regression coefficients predicting AA. The results showed that objectively measured total sedentary time was not associated with AA, after adjusting for potential confounders.  相似文献   
938.
The present study tested the cross-cultural generalizability of the measurement and structural parameters of the theory of planned behavior (TPB) among youth in a physical activity context. Pupils from five cultural groups completed measures of attitudes, subjective norms, perceived behavioral control (PBC), and intentions for physical activity. Five weeks later, participants completed self-report measures of physical activity behavior. Confirmatory factor analyses and multisample structural equation models revealed well-fitting models within each sample with minimal variations in the measurement parameters across cultures. There were a few significant cross-cultural differences in the structural relations among the TPB constructs. Attitudes predicted intentions in all samples (beta range = .300 to .550), whereas the effect of the subjective norms on intention was nonsignificant in all but the Hungarian sample (beta = .243). Conversely, the effect of PBC on intentions was significant (beta range = .302 to .573) in all but the Hungarian sample. Findings support the generalizability of the measures and pattern of effects for the TPB among young people in a physical activity context.  相似文献   
939.
Early Childhood Education Journal - The original version of this article unfortunately contained a typo in co-author name.  相似文献   
940.
To further examine what designers actually do as compared to what they should do, a study of designer practice based on the “Layers of Necessity” model was conducted. The data were surprisingly homogeneous given the heterogeneous composition of the group, all members of a local NSPI chapter. Results contribute to validation of the underlying ID model and confirm previous findings that designers do not systematically perform all the steps in any ID model. Certain trends were noted; namely, an increase in the perceived importance and frequency of pilot testing, the continuing importance of “Decision Already Made” as a reason for not performing a given step, and the parallel between the steps perceived as most necessary and those performed most often. Based on these data and other studies of ID practice, the future of ID practice appears to be moving toward design of learner-centered learning environments and increased use of prototyping in the design process.  相似文献   
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