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31.
Recent theories suggest that negative effects of fatigue on performance are determined by perception of effort and motivation rather than being directly caused by reaching physiological limits. In the current experiment, the influence of motivation on fatigue-induced decrements in soccer performance was experimentally investigated. Sixty amateur soccer players performed a validated soccer-passing test before and after a fatigue protocol. Results showed that players’ motivation and performance decreased after the fatigue protocol for players in the control group. In contrast, players in the motivation group (i.e., with motivation experimentally induced after the fatigue protocol) were able to uphold their motivation and increase their performance. These results indicate that motivation plays a crucial role in performance under fatigue, as fatigue-induced decrements in soccer passing performance can be counteracted by high levels of motivation. Future research may explore the limits of this counteracting effect and extend findings to other relevant performance aspects.  相似文献   
32.
Abstract

In recent years, volunteering has received strong research attention from both scholars and practitioners. For the most part, involvement in volunteer activities has been identified as an important determinant of future volunteering. Through revalidating an existing instrument, the purpose of this study was to assess the dimensions of volunteer satisfaction at the 2012 London Olympic Games and its impact on future volunteer behaviour. The findings of this study shed light on the identification of volunteer satisfaction factors in the mega sporting event setting, particularly for a unique type of volunteer (i.e. media worker) assigned to a special set of tasks. Unlike Galindo-Kuhn and Guzley’s results that revealed participation efficacy and group integration to be strong predictors of volunteer satisfaction, organizational support was the primary predictor for media centre volunteers’ re-participation intention towards future volunteering programmes.  相似文献   
33.
Inhibitory control is the capacity to suppress inappropriate responses. It is central to many aspects of development, most notably executive function and effortful control. Despite its importance, however, there are significant gaps in our understanding of inhibitory control’s early development, and several findings that remain hard to explain. Here, a new account of inhibitory control is presented, explaining previous findings by distinguishing between two distinct ways that inhibitory control is used. According to this “Strength/Endurance” account, inappropriate responses which are highly prepotent tax inhibitory strength; whereas inappropriate responses which remain active for a long time tax inhibitory endurance. The developmental trajectories of these two aspects of inhibitory control, and their separate impacts on broader development, are discussed.  相似文献   
34.
The present study aimed to investigate pre-sleep behaviours (including evening electronic device use) and sleep quantity in well-trained athletes. Seventy well-trained athletes (44 females, 26 males) aged 21 ± 4 y from a range of team and individual sports were asked to complete an online sleep diary for 7 days. The sleep diary included questions about pre-sleep behaviours (e.g. napping, caffeine intake), electronic device use in the 2 h prior to bedtime (e.g. type of device and duration of use) and sleep (e.g. time in bed, sleep onset latency). On average, athletes spent 8:20 ± 1:21 h in bed each night. Associations between age, time in bed and sleepiness suggested that younger athletes spent more time in bed (= -0.05, p = 0.001) but felt sleepier (r = -0.32, p < 0.01) than older athletes. On average, athletes mostly used electronic devices for 0–30 min prior to sleep. The use of multiple devices in the evening was associated with more perceived difficulty in falling asleep (= 0.22, p = 0.03), but no associations existed with other sleep variables. In summary, younger athletes may require later start times or improved sleep quality to resolve excessive sleepiness.  相似文献   
35.
Prior research indicates that providing participants with positive augmented feedback tends to enhance motor learning and performance, whereas the opposite occurs with negative feedback. However, the majority of studies were conducted with untrained participants performing unfamiliar motor tasks and so it remains unclear if elite athletes completing familiar tasks respond in a similar fashion. Thus, this study investigated the effects of three different versions of false-performance feedback on punching force (N), pacing (force over time) and ratings of perceived exertion (RPE) in 15 elite amateur male boxers. Athletes completed a simulated boxing bout consisting of three rounds with 84 maximal effort punches delivered to a punching integrator on four separate days. Day one was a familiarisation session in which no feedback was provided. In the following three days athletes randomly received false-positive, false-negative and false-neutral feedback on their punching performance between each round. No statistical or meaningful differences were observed in punching forces, pacing or RPE between conditions (> 0.05; ≤ 2%). These null results could stem from the elite status of the athletes involved, the focus on performance rather than learning, or they may indicate that false feedback has a less potent effect on performance than previously thought.  相似文献   
36.
ABSTRACT

This paper concludes the Special Issue (SI) ‘Probing the Amalgam: the relationship between science teachers’ content, pedagogical and pedagogical content knowledge’. We review the five papers (Sorge et al; Gess-Newsome et al; Kind; Pitjeng-Mosabala and Rollnick; and Liepertz and Bronowski) by discussing evidence these present regarding the relationships between content knowledge (CK), pedagogical knowledge (PK) and pedagogical content knowledge (PCK); the development of CK, PK and PCK in novice and experienced secondary science teachers and how CK, PK and/or PCK impact students’ learning. In conclusion, we draw these findings together in offering proposals for future research via reconsideration of Shulman’s amalgam. This includes post-hoc examination of a PCK model known as ‘the Consensus Model’ (Gess-Newsome, [2015]. A model of teacher professional knowledge and skill including PCK: Results of the thinking from the PCK Summit. In A. Berry, P. J. Friedrichsen, & J. Loughran (Eds.), Re-examining Pedagogical Content Knowledge in Science Education (pp. 28–42). New York, NY: Routledge; Neumann, Kind, & Harms [2018]. Probing the amalgam: The relationship between science teachers’ content, pedagogical and pedagogical content knowledge. International Journal of Science Education, 1–15) and presentation of a novel PCK structure based on evidence from the SI studies.  相似文献   
37.
Research suggests that spatial ability may predict success in complex disciplines including anatomy, where mastery requires a firm understanding of the intricate relationships occurring along the course of veins, arteries, and nerves, as they traverse through and around bones, muscles, and organs. Debate exists on the malleability of spatial ability, and some suggest that spatial ability can be enhanced through training. It is hypothesized that spatial ability can be trained in low-performing individuals through visual guidance. To address this, training was completed through a visual guidance protocol. This protocol was based on eye-movement patterns of high-performing individuals, collected via eye-tracking as they completed an Electronic Mental Rotations Test (EMRT). The effects of guidance were evaluated using 33 individuals with low mental rotation ability, in a counterbalanced crossover design. Individuals were placed in one of two treatment groups (late or early guidance) and completed both a guided, and an unguided EMRT. A third group (no guidance/control) completed two unguided EMRTs. All groups demonstrated an increase in EMRT scores on their second test (P < 0.001); however, an interaction was observed between treatment and test iteration (P = 0.024). The effect of guidance on scores was contingent on when the guidance was applied. When guidance was applied early, scores were significantly greater than expected (P = 0.028). These findings suggest that by guiding individuals with low mental rotation ability “where” to look early in training, better search approaches may be adopted, yielding improvements in spatial reasoning scores. It is proposed that visual guidance may be applied in spatial fields, such as STEMM (science, technology, engineering, mathematics and medicine), surgery, and anatomy to improve student's interpretation of visual content. Anat Sci Educ. © 2018 American Association of Anatomists.  相似文献   
38.
Research suggests that physical education (PE) in Western countries is not providing equitable experiences for non-white students. Responsibility for shortcomings has often been ascribed to white PE teachers. Scholars have claimed that teachers lack cultural competence and know little about how physical cultures or health are understood by the young people with whom they work. The objective of this investigation was to investigate this claim and generate an understanding of how white PE teachers in a culturally diverse high school make sense of their work with non-white students. Data with three Swedish teachers of varying experience were produced using semi-structured interviewing. A series of school visits provided a complementary line of data. Four themes emerged from the data. These related to: (1) differences between white and non-white values; (2) the knowledge and dispositions necessary for success in PE; (3) the broad purpose of PE, and; (4) the differences between boys’ and girls’ experiences of PE. Data were interpreted using a Critical Race Theory (CRT) perspective, with the notion of ‘whiteness’ providing a specific analytic concept. The general thesis developed in the second part of the paper is that problems result not from insensitivity or incompetence but from discourses of whiteness in which many teachers live and work. By building on critical research both in general education and physical education literature and by utilizing whiteness as an analytical concept, the investigation shows how three PE teachers draw extensively on the racial discourse of whiteness and how this disadvantages non-white students. The paper is concluded with a consideration of how racial disadvantage could be challenged or disrupted.  相似文献   
39.
The present study assessed neuromuscular and corticospinal changes during and after a fatiguing submaximal exercise of the knee extensors in different modes of muscle contraction. Twelve subjects performed two knee extensors exercises in a concentric or eccentric mode, at the same torque and with a similar total impulse. Exercises consisted of 10 sets of 10 repetitions at an intensity of 80% of the maximal voluntary isometric contraction torque (MVIC). MVIC, maximal voluntary activation level (VAL) and responses of electrically evoked contractions of the knee extensors were assessed before and after exercise. Motor evoked potential amplitude (MEP) and cortical silent period (CSP) of the vastus medialis (VM) and rectus femoris (RF) muscles were assessed before, during and after exercise. Similar reductions of the MVIC (?13%), VAL (?12%) and a decrease in the peak twitch (?12%) were observed after both exercises. For both VM and RF muscles, MEP amplitude remained unchanged during either concentric or eccentric exercises. No change of the MEP amplitude input–output curves was observed post-exercise. For the RF muscle, CSP increased during the concentric exercise and remained lengthened after this exercise. For the VM muscle, CSP was reduced after the eccentric exercise only. For a similar amount of total impulse, concentric and eccentric knee extensor contractions led to similar exercise-induced neuromuscular response changes. For the two muscles investigated, no modulation of corticospinal excitability was observed during or after either concentric or eccentric exercises. However, intracortical inhibition showed significant modulations during and after exercise.  相似文献   
40.
Young children show social preferences for resource-rich individuals, although few studies have explored the causes underlying such preferences. We evaluate the viability of one candidate cause: Children believe that resource wealth relates to behavior, such that they expect the resource rich to be more likely to materially benefit others (including themselves) than the resource poor. In Studies 1 and 2 (ages 4–10), American children from predominantly middle-income families (= 94) and Indian children from lower income families (= 30) predicted that the resource rich would be likelier to share with others than the resource poor. In Study 3, American children (= 66) made similar predictions in an incentivized decision-making task. The possibility that children's expectations regarding giving contribute to prowealth preferences is discussed.  相似文献   
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