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961.
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   
962.
This study aimed to validate the Sedentary Sphere posture classification method from wrist-worn accelerometers in children. Twenty-seven 9–10-year-old children wore ActiGraph GT9X (AG) and GENEActiv (GA) accelerometers on both wrists, and activPAL on the thigh while completing prescribed activities: five sedentary activities, standing with a phone, walking (criterion for all 7: observation) and 10-min free-living play (criterion: activPAL). In an independent sample, 21 children wore AG and GA accelerometers on the non-dominant wrist and activPAL for two days of free-living. Per cent accuracy, pairwise 95% equivalence tests (±10% equivalence zone) and intra-class correlation coefficients (ICC) analyses were completed. Accuracy was similar, for prescribed activities irrespective of brand (non-dominant wrist: 77–78%; dominant wrist: 79%). Posture estimates were equivalent between wrists within brand (±6%, ICC > 0.81, lower 95% CI ≥ 0.75), between brands worn on the same wrist (±5%, ICC ≥ 0.84, lower 95% CI ≥ 0.80) and between brands worn on opposing wrists (±6%, ICC ≥ 0.78, lower 95% CI ≥ 0.72). Agreement with activPAL during free-living was 77%, but sedentary time was underestimated by 7% (GA) and 10% (AG). The Sedentary Sphere can be used to classify posture from wrist-worn AG and GA accelerometers for group-level estimates in children, but future work is needed to improve the algorithm for better individual-level results.  相似文献   
963.
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   
964.
In this study, we examined the factor structure and reliability of the Korean Quality of Life (KQoL) survey and compared the KQoL survey to both the World Health Organization Quality of Life-Brief Version (WHOQOL-BREF) and the Satisfaction with Life Scale (SWLS). We also assessed associations between KQoL scores and physical activity (PA) participation. Participants were 557 (male = 281, female = 276) healthy Korean adults with ages between 18 and 71 years (M = 33.2, SD = 14.2). Results of confirmatory factor analyses confirmed the 7-subscale model and indicated acceptable values supporting convergent validity (χ2 = 1,678.758, df = 443, p < .001, RMSR = .045, RMSEA = .071, TLI = .880, CFI = .892). Correlations of KQoL subscales with similar subscales of WHOQOL-BREF and with SWLS supported concurrent validity. Results confirm that the KQoL survey can assess multidimensional aspects of quality of life (QoL), including spiritual, physical, social, and psychological. KQoL scores were positively related to PA participation, in line with previous research supporting the positive association of PA with QoL.  相似文献   
965.
Transitioning into faculty roles can be a challenging experience. Responsibilities related to teaching, research, and service can be difficult to balance, and mismatch between personal preferences for work focus and instructional expectations can be problematic. This is particularly true of visiting assistant professors who want to work toward tenure-track positions, but whose current job focus is on teaching. Through transformative learning theory and employing the methodologies of self-study, we sought to understand the experiences of Kevin, the second author and a first-year visiting assistant professor. We draw data from Kevin's reflective journal and discussions between Kevin and his critical friend, Jim. Themes included (a) becoming an academic, (b) a hard-wired disposition toward work, and (c) influence of the VAP on emotional and personal health. Results are discussed through the lens of transformative learning theory and focus on Kevin's growth during his year as a visiting assistant professor.  相似文献   
966.
Increased activity of multiple stakeholders (e.g. agents and owners) have created new challenges for some coaches working in professional sports clubs. The purpose of this project was to draw attention to the normative or accepted practices inherent in sport work, some of the day-to-day realities of some coaches working in this context, and to understand how coaches’ perceptions of other stakeholders come to bear on their individual circumstances, career expectations/objectives and professional agency. Data were generated from semi-structured interviews with seven professional basketball coaches who worked in top-level European clubs. The analysis reveals the coach’s relationships between some owners and agents differed with respect to exercising professional agency, and, coach’s decisions and actions were tied to their professional ideals as well as understandings of what they need to undertake their work effectively and negotiation and/or adjustment strategies. Occasionally coach’s work practices could be viewed as antithetical to employment security, however, the presence of insecurity was at times embraced and used strategically to affect workers’ career decisions. Amid contemporary regional geo-political shifts, this work aids examinations of global sport settings, structures and issues that may contour sporting professionals’ lives.  相似文献   
967.
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   
968.
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   
969.
The aim of this article is to explore the experiences of female elite-level Norwegian coaches in football. More precisely, we wanted to find out the meaning of gender for these coaches’ football experiences. The results presented are based on five in-depth interviews with female elite-level coaches between 36 and 50 years of age. A feminist cultural and a gender perspective are used to understand and discuss the findings. As shown in other studies, the culture of football in Norway is very gendered. This has an impact on the female football coaches’ experiences, both in relation to how they perceive their own role, their coach education and with respect to their self-confidence and how they look upon their own chances in the job market. As a group, they represent a form of pariah femininity, and very little resistance femininity and a liberal feminist perspective, i.e. equality on the men’s premises.  相似文献   
970.
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   
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