Self-Controlled Amount of Practice Benefits Learning of a Motor Skill

Abstract

Self-control over factors involving task-related information (e.g., feedback) can enhance motor learning. It is unknown if these benefits extend to manipulations that do not directly affect such information. The purpose of this study was to determine if self-control over the amount of practice would also facilitate learning. Participants learned to throw a dart using their nonpreferred hand. The self-control (SC) group decided when to stop practice. The yoked group completed the same number of trials as their SC counterparts. Results revealed the SC group was more accurate during transfer and in recalling the number of trials completed. These findings indicate that self-control benefits extend to factors that do not directly alter task-related information.     

Generation Psy: Student characteristics and academic achievement in a three-year problem-based learning bachelor program

This study investigated the simultaneous impact of demographic, personality, intelligence, and (prior) study performance factors on students' academic achievement in a three-year academic problem-based psychology program. Information regarding students' gender, age, nationality, pre-university education, high school grades, Big Five personality traits, intelligence (i.e., numerical, verbal, spatial), observed learning activities, and self-study time was collected among almost 1800 students enrolled in this psychology bachelor program at Erasmus University Rotterdam between 2003 and 2009. Academic achievement was measured by students' yearly number of acquired credit points, a course test, and a knowledge progress test. Multiple regression analyses showed that observed learning activities, first- and second-year performance, high school grades, conscientiousness, and verbal ability were most strongly and consistently related to academic achievement in the bachelor. Other student factors also contributed to academic achievement, but their influence was less prominent and mainly restricted to the first year. These results suggest that (prior) educational achievements and observable learning activities are most important for academic success in a problem-based learning bachelor program.     

The Effect of School Culture on Science Education at an Ideologically Innovative Elementary Magnet School: An Ethnographic Case Study

This ethnographic case study investigated the science practices of teachers at one public elementary magnet school in light of how school culture influenced science curriculum design and instruction. The purpose of the study was to address how school culture impacted the school??s overall treatment of science as a viable content area. Key informant teachers were interviewed to explore their personal beliefs and values, teaching, access to materials, and views of the adopted integrated thematic curriculum model and magnet structure. The resulting data, triangulated with informal observation and artifact collection, were analyzed using a theoretical framework that emphasized five interdependent school culture indicators (values, beliefs, practices, materials, and problems). Findings suggest that the school??s culture adversely influenced the treatment of science.     

Impact forces and neck muscle activity in heading by collegiate female soccer players

Three soccer header types (shooting, clearing and passing) and two heading approaches (standing and jumping) were manipulated to quantify impact forces and neck muscle activity in elite female soccer players. The 15 participants were Division I intercollegiate soccer players. Impact forces were measured by a 15-sensor pressure array secured on the forehead. The electromyographic (EMG) activity of the left and right sternocleidomastoid and trapezius muscles was recorded using surface electrodes. Maximum impact forces and impulses as well as the EMG data were analysed with separate repeated-measures analyses of variance. Impact forces and impulses did not differ among the header types or approaches. Higher values were found for jumping versus standing headers in the mean normalized EMG for the right sternocleidomastoid. In addition, the integrated EMG was greater for the right sternocleidomastoid and right and left trapezius (P < 0.05). The sternocleidomastoid became active earlier than the trapezius and showed greater activity before ball contact. The trapezius became active just before ball contact and showed greater activity after ball contact. The increased muscle activity observed in the neck during the jumping approach appears to stabilize the connection between the head and body, thereby increasing the stability of the head-neck complex.     

Severity and cost of injuries in amateur rugby league: a case study

The aim of this study was to determine the severity and cost of injuries in amateur rugby league. Seventy-two amateur rugby league players aged 28 +/- 6 years (mean +/- s) were surveyed at the end of a competitive season. An injury was defined as any pain, disability or injury that occurred as a result of a competition game which caused the player to miss subsequent games. Injuries were classified as minor (one game missed), moderate (two to four games missed) and major (five or more games missed). Of the 72 questionnaires distributed, 34 (47.2%) were returned. Twenty respondents (58.8%) sustained an injury that resulted in one or more missed games. Eight injured players (40.0%) missed five or more training sessions, six of whom (30%) missed five or more games as a result of the injury. The median time lost from employment or study for all injured players was 2 days per playing injury. The respective median direct (e.g. medical expenses) and indirect (e.g. wages lost) costs associated with the injury were 28.29 pounds and 77.04 pound per playing injury. A considerable proportion of injuries sustained in the present sample of amateur rugby league players were major, resulting in a loss of training, playing and employment or study time, and these injuries were associated with significant direct and indirect economic costs. Further studies, using a larger sample, would complement the present findings in establishing the severity and cost of amateur rugby league injuries. These results suggest that prevention strategies are required to reduce the severity and cost of amateur rugby league injuries.     

eSport: Vom Präfix zum Thema für den organisierten Sport!?

In an increasingly differentiated culture of movement, play and sport as well as a more and more digitized society, the topic of eSports has been intensively discussed in recent time. The objective-categorical basics of the discussion seem to be clear only at first sight. A closer look points to the need of a differentiated cross-disciplinary discussion of the topic. It becomes clear that above all the underlying understanding of sport, the content-related demarcation as well as the social positioning contribute decisively to the perception of eSport (approval/rejection). The present article takes up the discussion with reference to the heterogeneity, heteronomy and complexity of sports and provides an alternative interpretive idea on the topic.     

那一场失约的雪

妈妈把我塞进被窝.妈妈,真的要下雪吗?她把毯子一直拉到我的下巴,在我脸上亲了一下.天气预报是这样说的.     

Beyond Warmth and Conflict: The Developmental Utility of a Boundary Conceptualization of Sibling Relationship Processes

Translating relationship boundaries conceptualizations to the study of sibling relationships, this study examined the utility of sibling enmeshment and disengagement in predicting child adjustment difficulties in a sample of 282 mothers and adolescents (mean age = 12.7 years). Mothers completed a semistructured interview at the first measurement occasion to assess sibling interaction patterns. Adolescents, mothers, and teachers reported on children’s adjustment problems across 2 annual waves of assessment. Supporting the incremental utility of a boundary conceptualization of sibling relationships, results of latent difference score analyses indicated that coder ratings of sibling enmeshment and disengagement uniquely predicted greater adolescent adjustment difficulties even after taking into account standard indices of sibling relationship quality (i.e., warmth and conflict) and sibling structural characteristics (e.g., sex).     

Explaining common variance shared by early numeracy and literacy

How can be explained that early literacy and numeracy share variance? We specifically tested whether the correlation between four early literacy skills (rhyming, letter knowledge, emergent writing, and orthographic knowledge) and simple sums (non-symbolic and story condition) reduced after taking into account preschool attention control, short-term memory, speed of processing, visual-spatial skills, vocabulary, and shared book reading. 228 Dutch native preschoolers (mean age 54.25; SD = 2.12 months) participated. The results revealed that 1) all literacy skills were related to sums (non-symbolic and story condition), 2) rhyming was the strongest predictor of non-symbolic sums, and letter knowledge of sums in story context, 3) visual-spatial skills explained part of the shared variance in the non-symbolic condition and visualspatial skills, vocabulary and short-term memory explained part of the shared variance in sums in story context. Implications for the preschool curriculum and early interventions are discussed.     

Statistical modelling of knee valgus during a continuous jump test

Landing with the knee in a valgus position is recognized as a risk factor for anterior cruciate ligament (ACL) injury. Using linear and non-linear regression analyses, the purpose of this study was to examine the correlation between two-dimensional (2D) knee valgus and three-dimensional (3D) knee kinematics measured during a jump landing task. Twenty-eight female collegiate athletes participated. All participants were required to perform a continuous jump test. The average maximum angles of abduction and internal tibial rotation during landing were measured using the Point Cluster Technique. Average peak knee valgus angle was measured using a 2D approach. Linear and non-linear regression analyses between 2D valgus and 3D knee abduction, and between 2D valgus and 3D internal tibial rotation, were performed. The R2 value between 2D valgus and 3D knee abduction was significantly different from zero and had a moderate correlation for all models, whereas the R2 value between 2D valgus and 3D internal tibial rotation was not significantly different from zero. The 2D approach could be used to screen a specific group of individuals for risk of ACL injury; however, using frontal plane 2D analysis of valgus motion to evaluate internal tibial rotation is not advised.