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1.
Dan J. Miller Garry Kidd Peter T. F. Raggatt Kerry Anne McBain Wendy Li 《Communication Research Reports》2020,37(3):110-121
ABSTRACT The idea that pornography promotes sexism is a commonly purported one. This study employed an online sample of heterosexual men (N = 323) to investigate the relationship between pornography use (in terms of both overall level of pornography use and use of violent and/or humiliating pornography) and old-fashioned and modern sexism. The moderating effects of agreeableness and perceived realism of pornography were also assessed. Level of general pornography use and use of violent and/or humiliating pornography was not predictive of either sexism measure. Agreeableness was negatively predictive of both sexism measures, whereas perceived realism was positively predictive of sexism. Agreeableness and perceived realism did not moderate the relationship between level of pornography use and any of the outcome measures. 相似文献
2.
Samuel J. Callaghan Robert G. Lockie Warren A. Andrews Robert F. Chipchase Sophia Nimphius 《Sports biomechanics / International Society of Biomechanics in Sports》2020,19(3):307-321
AbstractThis study assessed the reliability and validity of segment measured accelerations in comparison to front foot contact (FFC) ground reaction force (GRF) during the delivery stride for cricket pace bowlers. Eleven recreational bowlers completed a 30-delivery bowling spell. Trunk- and tibia-mounted inertial measurement units (IMUs) were used to measure accelerations, converted to force, for comparisons to force plate GRF discrete measures. These measures included peak force, impulse and the continuous force–time curve in the vertical and braking (horizontal) planes. Reliability and validity was determined by intra-class correlation coefficients (ICC), coefficient of variation (CV), Bland–Altman plots, paired sample t-tests, Pearson’s correlation and one-dimensional (1D) statistical parametrical mapping (SPM). All ICC (0.90–0.98) and CV (4.23–7.41%) were acceptable, except for tibia-mounted IMU braking peak force (CV = 12.44%) and impulse (CV = 18.17%) and trunk vertical impulse (CV = 17.93%). Bland–Altman plots revealed wide limits of agreement between discrete IMU force signatures and force plate GRF. The 1D SPM outlined numerous significant (p < 0.01) differences between trunk- and tibia-located IMU-derived measures and force plate GRF traces in vertical and braking (horizontal) planes. The trunk- and tibia-mounted IMUs appeared to not represent the GRF experienced during pace bowling FFC when compared to a gold-standard force plate. 相似文献
3.
Ann Bailey James Funk David Lessley Chris Sherwood Jeff Crandall William Neale 《Sports biomechanics / International Society of Biomechanics in Sports》2020,19(5):678-700
ABSTRACT Professional American football games are recorded in digital video with multiple cameras, often at high resolution and high frame rates. The purpose of this study was to evaluate the accuracy of a videogrammetry technique to calculate translational and rotational helmet velocity before, during and after a helmet impact. In total, 10 football impacts were staged in a National Football League (NFL) stadium by propelling helmeted 50th percentile male crash test dummies into each other or the ground at speeds and orientations representative of concussive impacts for NFL players. The tests were recorded by experienced sports film crews to obtain video coverage and quality typically available for NFL games. A videogrammetry procedure was used to track the position and rotation of the helmet throughout the relevant time interval of the head impact. Compared with rigidly mounted retroreflective marker three dimensional (3-D) motion tracking that was concurrently collected in the experiments, videogrammetry accurately calculated changes in translational and rotational velocity of the helmet using high frame rate (two cameras at 240 Hz) video (7% and 15% error, respectively). Low frame rate (2 cameras at 60 Hz) video was adequate for calculating pre-impact translational velocity but not for calculating the translational or rotational velocity change of the helmet during impact. 相似文献
4.
Garrett F. Beatty Christopher M. Janelle 《International review of sport and exercise psychology》2020,13(1):266-296
ABSTRACT Adaptive regulation of emotions is imperative for successful sport performance. However, the lion’s share of mainstream emotion regulation (ER) literature is founded on perspectives prioritising mental health, not performance. Consequently, ER strategies are predominantly classified as adaptive or maladaptive based on effectiveness in achieving targeted mental health outcomes. These conventional mental health classifications can catalyse misapplication of ER strategies within sport and other motor performance contexts when (1) ER motives are instrumentally directed towards performance enhancement and (2) Minimal consideration is given to the consequences of ER on the coordination and execution of motor actions. Herein, we review the current state of relevant ER research within and outside of sport contexts. We also present a novel conceptual framework, the Temporal Influence Model of Emotion Regulation (TIMER). TIMER proposes that ER strategies exert distinct, temporally dependent demands upon perceptual-cognitive and motoric resources. These unique regulatory profiles influence subsequent motor performance outcomes. Critically, the degree to which regulatory strategies are appropriate or ideal varies given environmental constraints along with performers’ affective and performance goals. The model includes testable hypotheses to guide theoretical and applied research in the domain of ER within sport and other motor performance contexts. 相似文献
5.
Jesús Vera Raimundo Jimnez David Crdenas Beatriz Redondo Jos Antonio García 《运动与健康科学(英文)》2020,9(6):587-594
BackgroundAthletes tend to have better visuo-motor performance than do sedentary individuals. However, several basic visual-function and perceptual parameters remain unexplored to date. In this study, we investigated whether differences exist in visual function, performance, and processing between basketball players and individuals without a sport-involvement background.MethodsA total of 33 healthy men with no visual impairment or pathology were divided into 2 groups, depending on the involvement in sport (semi-professional basketball players and sedentary individuals). We tested their baseline heart-rate variability in the resting position apart from subjective questionnaires to determine their physical fitness level, and we checked their visual function, performance, and processing through an extended battery of optometric tests.ResultsThe 2 groups differed in resting heart-rate variability parameters (p < 0.001), confirming their dissimilarities in regular time practising sports per week. The basketball players showed a closer breakpoint and recovery nearpoint of convergence, a higher fusional-vergence rate, better discriminability halos, and better eye–hand coordination (all p values < 0.05).ConclusionThese results show evidence that athletes, basketball players in this case, exhibit better performance in several visual abilities in comparison to a group of individuals without sporting backgrounds, suggesting an improvement due to the systematic involvement of those skills during basketball practice. 相似文献
6.
Maddison J. Jones Brian Dawson Daniel F. Gucciardi Peter R. Eastwood Joanna Miller Shona L. Halson 《Journal of sports sciences》2019,37(8):864-870
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 (B = -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 (B = 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
7.
Baris Uslu Alper Calikoglu F. Nevra Seggie Steven H. Seggie 《Higher Education Quarterly》2019,73(3):285-311
The innovative teaching, knowledge and technology production and societal service activities of academics are largely discussed within the entrepreneurial university discourse in Higher Education journals. Therefore, this research focuses on a meta‐synthesis of Higher Education articles to better understand the concepts of the entrepreneurial university and entrepreneurial academic. After the systematic elimination based on keywords and titles, 25 articles have been selected from the top 10 Higher Education journals in the SCImago Journal Rankings. Content analysis was performed on these articles to highlight the common operational areas in entrepreneurial universities and activities of entrepreneurial academics. The meta‐synthesis shows that, both for universities and academics, entrepreneurship is overwhelmingly characterised by the commercialisation of scholarly activities that enrich institutional income revenue as well as academics’ personal income. However, such an approach can distance universities from their mission of public good; so Higher Education administrators should create mechanisms that would allow both to take place in a balanced way. 相似文献
8.
Fernandez Frank Baker David P. Fu Yuan-Chih Muñoz Ismael G. Ford Karly Sarita 《Minerva》2021,59(1):79-98
Minerva - Over the course of the 20th century, unprecedented growth in scientific discovery was fueled by broad growth in the number of university-based scientists. During this period the American... 相似文献
9.
Harry F. Dorrell Joseph M. Moore Mark F. Smith Thomas I. Gee 《Journal of sports sciences》2019,37(1):67-73
This study investigated the validity and reliability of the GymAware PowerTool (GPT). Thirteen resistance trained participants completed three visits, consisting of three repetitions of free-weight back squat, bench press, deadlift (80% one repetition maximum), and countermovement jump. Bar displacement, peak and mean velocity, peak and mean force, and jump height were calculated using the GPT, a three-dimensional motion capture system (Motion Analysis Corporation; 150 Hz), and a force plate (Kistler; 1500 Hz). Least products regression were used to compare agreeability between devices. A within-trial one-way ANOVA, typical error (TE; %), and smallest worthwhile change (SWC) were used to assess reliability. Regression analysis resulted in R2 values of >0.85 for all variables excluding deadlift mean velocity (R2 = 0.54–0.69). Significant differences were observed between visits 3-2 for bench press bar displacement (0.395 ± 0.055 m; 0.383 ± 0.053 m), and deadlift bar displacement (0.557 ± 0.034 m; 0.568 ± 0.034 m). No other significant differences were found. Low to moderate TE (0.6–8.8%) were found for all variables, with SWC ranging 1.7–7.4%. The data provides evidence that the GPT can be used to measure kinetic and kinematic outputs, however, care should be taken when monitoring deadlift performance. 相似文献
10.
David Sánchez-Oliva Rebecca M. Leech Alberto Grao-Cruces Irene Esteban-Cornejo Carmen Padilla-Moledo Oscar L. Veiga 《Journal of sports sciences》2020,38(9):1062-1069
ABSTRACTThe aims of this study were to identify profiles of sedentary behaviour (SB) patterns, based on leisure-time self-reported SB modalities (screen, educative, social, and relaxing) and to evaluate changes in these profiles over 2 years among Spanish youth aged 8–18 years. Latent profile analysis (LPA), a data-driven analytic approach, was used to identify groups of boys and girls (n = 1553; 48% girls; mean±SD age: 12.56 ± 2.49 y) with distinct SB profiles using the SB modalities (time/d) as input variables. Latent transition analysis, an extension of LPA that uses longitudinal data, was used to analyse 2-year changes in these profiles. At baseline, four and three SB profiles were found among boys (labelled: screen, educative, social, and relaxing) and girls (labelled: screen/social, educative, and relaxing), respectively. Overall, more girls (range: 48%-67%) had the same profile over time, than boys (40%-52%). Participants with a screen or relaxing SB profile at baseline were more likely to have an educative profile after 2 years. Youth with a social and an educative SB profile at baseline were more likely to transition to profiles characterized by higher screen and social SB, respectively. Using a novel and person-centered approach, this study identified gender-specific SB profiles that were moderately stable over time. 相似文献