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971.
972.
The purpose of this study was to examine the factorial invariance of the Abbreviated Neighborhood Environment Walkability Scale (NEWS-A) across subgroups based on demographic, health-related, behavioral, and environmental characteristics among Nurses’ Health Study participants (N = 2,919; age M = 73.0, SD = 6.9 years) living in California, Massachusetts, and Pennsylvania. A series of multigroup confirmatory factor analyses were conducted to evaluate increasingly restrictive hypotheses of factorial invariance. Factorial invariance was supported across age, walking limitations, and neighborhood walking. Only partial scalar invariance was supported across state residence and neighborhood population density. This evidence provides support for using the NEWS-A with older women of different ages, who have different degrees of walking limitations, and who engage in different amounts of neighborhood walking. Partial scalar invariance suggests that researchers should be cautious when using the NEWS-A to compare older adults living in different states and neighborhoods with different levels of population density.  相似文献   
973.
The analysis of sport performance in competitive contexts has become synonymous with the use of a range of software applications and hardware e.g. heart rate monitors and gps systems. With the prevalence of technology in mind, a small but growing corpus of literature has begun to consider this phenomenon and its influence upon the coaching process. This study adds to this literature by detailing the autoethnographic experiences of a case study coach; Derek. A contextualised and richly described narrative account of Derek’s experience of using coaching applications is provided. Analysis of Derek’s narrative suggests that technology can be a useful means by which individuals make sense of their experience. Specifically, (1) technology can be a ‘ready-to-hand’ instrument that enhances the coaching process. Unfortunately, (2) technology may become the only and ‘calculative’ means by which individuals come to understand their performance. In such instances, it is important to note that (3) the videos we use to understand our performance are transformed and incomplete representations of lived athletic experiences. Thus, Derek’s story illustrates how technology can be both an enabler and barrier to athletes who wish to holistically understand their own lived experiences and engage in coach-athlete relationships. The accompanying analysis draws upon concepts from Heideggerian philosophy to add insight into the use of technology within the coaching process. In so doing, the study prompts coaches to critically view their coach-athlete relationships as situated in a wider world which contains, and can be mediated by, technology. In addition, Derek’s story (re)directs researchers and coaching practitioners interested in technology to a useful literature (philosophy of technology) which may further inform their understanding of coach-athlete relationships.  相似文献   
974.
Background: A student’s choice to engage in a learning task is highly related to the student’s environmental stimuli and his or her perception of interest. From this perspective, the construct of situational interest (SI) has been used to interpret students’ motivation in task engagement. SI is assumed to be transitory, environmentally activated, and context specific. It has been conceptualized as a multidimensional construct with five dimensions: instant enjoyment, exploration intention, attention demand, novelty, and challenge. Few prior studies have compared SI between girls and boys in physical education (PE) contexts, and these studies have offered contrasting findings. They were conducted in coeducational (coed) or single-sex contexts and used learning tasks centred on a variety of outcomes: technical or tactical skills, creativity and cultural understanding.

Purpose: In the context of the debate on single-sex and coed classes in PE, this study aimed to estimate the effects of single-sex and coed PE classes on students’ situational interest (SI) within learning tasks centred on technical skills. The researchers decided to study learning tasks centred on the development of students’ technical skills, since these tasks are often used by teachers in PE.

Participants: The sample consisted of 177 Swiss secondary school students, aged 11–17 years (M?=?14.07, SD?=?1.41, 96 boys, 81 girls).

Data collection: The students completed the French 15-item SI Scale after practising a technical learning task in single-sex and coed PE contexts. The researchers chose five physical activities (i.e. athletics, basketball, dance, gymnastics, and volleyball), which are commonly taught in the state of Vaud (Switzerland) and provide a balance between masculine and feminine activities.

Data analysis: A two-way repeated-measures MANOVA was performed to examine the main and interaction effects of student sex and class sex composition on the five SI dimensions.

Findings: The results showed a main effect of class sex composition on student SI but no main effect of student sex and no interaction effect of student sex and class sex composition. More precisely, the scores for three SI dimensions (i.e. instant enjoyment, exploration intention, and attention demand) were higher in the coed context than in the single-sex context.

Conclusions: This study encourages teachers to propose coed PE classes to enhance students’ motivation and engagement when practising learning tasks centred on technical skills. This study offers supplementary evidence of the teacher’s role in promoting student SI. Beyond accounting for students’ dispositional factors (e.g. sex), PE teachers can significantly impact students’ SI in technical learning tasks through instructional choices.  相似文献   
975.
Magnetic-inertial measurement units (MIMUs) are becoming more prevalent in sports biomechanics and may be a viable tool to evaluate kinematic parameters. This study examined the accuracy of a MIMU to estimate orientation angles under static conditions and dynamically from a squash racket during a forehand drive shot. A MIMU was mounted onto a goniometer and moved through 0–90°, with static data collected at 10° increments during 10 repetitions of all three axes. Typical error analyses showed the MIMU to be very reliable (TE ≤ 0.03°). MIMU accuracy was determined via intraclass correlation coefficients (ICC) (r > 0.999, p < 0.001). An ordinary least products regression showed no proportional bias and minimal fixed bias for all axes. Dynamic accuracy was assessed by comparing MIMU and optical motion capture data of squash racket swing kinematics. A MIMU was fixed onto a racket and 10 participants each hit 10 forehand shots. Mean orientation angle error at ball impact was <0.50° and ICC showed very high correlations (r ≥ 0.988, p < 0.001) for all orientations. Swing phase root mean squared errors were ≤2.20°. These results indicate that a MIMU could be used to accurately and reliably estimate selected racket swing kinematics.  相似文献   
976.
Based on technological and analytical advances, the capability to more accurately and finitely examine biomechanical and skill characteristics of movement has improved. The purpose of this study was to use Inertial Measurement Units (IMUs) and Functional Principal Components Analysis (fPCA) to examine the role of movement variability (assessed via angular velocity), on 2 divers (1 international level; 1 national) performing the forward 3½ pike somersault dive. Analysis of angular velocity curves during ive-flight identified 5 fPCs, accounting for 96.5% of movement variability. The national diver’s scatter plots and standard deviation of fPC scores illustrated larger magnitudes of angular velocity variability across dive flight. For fPC1 and fPC3, magnitudes of SD variability were 282.6 and 201.5, respectively. The international diver illustrated more consistent angular velocity profiles, with clustering of fPCs scores (e.g., fPC1 & 3 = SD’s of 75.2 & 68.0). To account for lower variability in the international diver, the ability to better coordinate movement sequences and functionally utilise feedback in response to initiation of the somersault position is highlighted. Overall, findings highlight how both IMUs and fPCA can more holistically and finitely examine the biomechanical and skill characteristics of movement sequences with the capability to inform athlete development.  相似文献   
977.
This qualitative, exploratory study examines issues of age and aging surrounding mega-serial (daily soap opera) production in Tamil Nadu, India. This study is timely for demographic reasons (a rapidly aging Indian population) and for the centrality of mega-serials to India’s entertainment landscape, coupled with the genre’s long history of engaging global audiences with real-world social issues. Two data sources are utilized: focus groups with 16 mega-serial viewers and interviews with 25 members of the Tamil mega-serial industry. Situated in scholarship on gerontology/age studies and media/culture industry studies, analysis yields two broad themes related to (a) representations of age/aging and elder-oriented storylines in contemporary Tamil mega-serials and (b) recent industry changes that may forestall mega-serials’ potential to center age and aging as core narrative elements. Overall, evidence points to an industry and audience(s) in considerable transition.  相似文献   
978.
979.
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   
980.
During soccer matches, performance decrements have been reported that relate to both physical abilities and technical skills. To investigate the effects of low-frequency electrical stimulation LFES (VeinoplusSport®, Ad Rem Technology, France) administered during half-time recovery on performance alterations during the second half. Twenty-two highly trained young players undertook a soccer-match simulation (SAFT90). During half-time, they were randomly assigned to LFES group or Placebo group. Each half was split into 3 bouts of 12 minutes. Following each bout, maximal strike speed (MSS), sprint test (ST), maximal sprint accelerations (MA) and metabolic power (MP) were determined in both groups. Arterial (AF) and venous flows (VF) were measured at rest and at the end of half-time. LEFS group exhibited beneficial effects on performance compared to the Placebo group with a likely effect for MSS, ST, MA, and a possible effect for MP. AF and VF increased statistically more in LEFS group compared to Placebo group. The use of specific calf-pump LFES during half-time of a youth simulated soccer match attenuated the decrease in performance during the second half compared to Placebo group. This effect is most marked at the beginning of the second half with regards to explosive parameters.  相似文献   
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