Tensiomyographical responses to accelerometer loads in female collegiate basketball players     

Kyle D. Peterson  Gabriela T. Quiggle 《Journal of sports sciences》2017,35(23):2334-2341

The purpose of the present study was to characterise the relationship between relative versus absolute internal and external loads in collegiate basketball players throughout the course of a season. Five Division I basketball players wore triaxial accelerometers throughout the 2015–2016 season and were tensiomyographically assessed weekly. One-way repeated-measure analysis of variance (RM ANOVA) with least-significant-difference (LSD) pairwise comparisons was used to determine which absolute weekly loads were different across the season. Cohen’s d was used to supplement the determination of meaningful relative load changes. Overall RM ANOVA models suggest absolute external load differences occurred (PlayerLoad? F = 17.63; IMA? F = 31.63). Two-way RM ANOVA models revealed main effect differences were revealed between muscle groups for Tc (F = 9.11) and Dm (F = 3.25). Meaningful relative load changes between weeks were observed for both external and internal. The present study observed that tensiomyography utilised as a tool to monitor internal load may be more suitable for detecting fatigue from relative external load changes versus absolute load attained. Limiting weekly training volume changes to ≤10% may maintain appropriate adaptation. Mediolateral plane IMA? and adductor longus muscle group may be pertinent metrics when monitoring female collegiate basketball athletes.  相似文献   

Increasing hip and knee flexion during a drop-jump task reduces tibiofemoral shear and compressive forces: implications for ACL injury prevention training     

Liang-Ching Tsai  Yi-An Ko  Kyle E. Hammond  John W. Xerogeanes  Gordon L. Warren  Christopher M. Powers 《Journal of sports sciences》2017,35(24):2405-2411

Although most ACL injury prevention programmes encourage greater hip and knee flexion during landing, it remains unknown how this technique influences tibiofemoral joint forces. We examined whether a landing strategy utilising greater hip and knee flexion decreases tibiofemoral anterior shear and compression. Twelve healthy women (25.9 ± 3.5 years) performed a drop-jump task before and after a training session (10–15 min) that emphasised greater hip and knee flexion. Peak tibiofemoral anterior shear and compressive forces were calculated using an electromyography (EMG)-driven knee model that incorporated joint kinematics, EMG and participant-specific muscle volumes and patella tendon orientation measured using magnetic resonance imaging (MRI). Participants demonstrated a decrease in peak anterior tibial shear forces (11.1 ± 3.3 vs. 9.6 ± 2.7 N · kg^?1; P = 0.008) and peak tibiofemoral compressive forces (68.4 ± 7.6 vs. 62.0 ± 5.5 N · kg^?1; P = 0.015) post-training. The decreased peak anterior tibial shear was accompanied by a decrease in the quadriceps anterior shear force, while the decreased peak compressive force was accompanied by decreased ground reaction force and hamstring forces. Our data provide justification for injury prevention programmes that encourage greater hip and knee flexion during landing to reduce tibiofemoral joint loading.  相似文献   

Join the Club: Food Advertising, 1930s Children's Popular Culture,and Brand Socialization     

Kyle Asquith 《Popular Communication》2014,12(1):17-31

Relying upon archival research, this article examines children's food advertising during the 1930s. More specifically, I highlight advertiser-created “clubs.” As a complement to 1930s radio and comic strip sponsorships, dozens of national food brands introduced “clubs” for children. Through a series of case studies, I argue that by creating these clubs, national food advertisers embedded themselves in children's popular culture with the outcome of brand socialization—not simply immediate sales. These clubs offered access to exclusive branded communities, encouraging children to be brand-conscious and brand-loyal consumers. Unlike toy advertisers, who did not enter children's popular culture until the television era, food advertisers sold products meant to be consumed daily; as such, brand loyalty was highly sought after.  相似文献   

Individual and community practices for constructing communicative resilience: exploring the communicative processes of coping with parental alienation     

Kristina M. Scharp  Kyle F. Kubler  Tiffany R. Wang 《Journal of Applied Communication Research》2020,48(2):207-226

ABSTRACT

Parental alienation occurs after parents divorce and intentionally or even unintentionally persuade their children to distance themselves from or reject the other parent. Framed by the communication theory of resilience, this study explores the communicative practices that enable and constrain the targeted alienated parents’ ability to create normalcy at the individual and online community levels. We also examine the relationships between individual-level and online community-level resilience. Findings from 40 narrative interviews reveal communicative practices/processes that enable and constrain alienated parents at both the individual and online support group levels. Findings also suggest that there is a robust relationship between resilience practices at the individual and community levels. Theoretical implications and practical applications are discussed.  相似文献   

Children's Experiences of Bullying Victimization and the Influence on Their Subjective Well-Being: A Multinational Comparison     

Shazly Savahl  Carme Montserrat  Ferran Casas  Sabirah Adams  Habib Tiliouine  Elizabeth Benninger  Kyle Jackson 《Child development》2019,90(2):414-431

The study used data from the second wave of the Children's Worlds Survey to explore the relation between children's experiences of bullying victimization (physical and psychological) and their subjective well-being (SWB) across three age groups (8, 10, and 12) and 15 global geographical regions. The sample consists of 47,029 children randomly selected from 15 countries. Data were analyzed using structural equation modeling and multigroup confirmatory factor analysis. The results show appropriate fit structure for the overall model, and that the combined influence of physical and psychological bullying made a significant contribution to SWB across age groups and geographical regions. The findings are interpreted using Cummins's (1995) Homeostasis Theory of SWB.  相似文献   

Acknowledging our colleagues     

William C. Kyle 《科学教学研究杂志》1995,32(10):1129-1129

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Acknowledgment     

William C. Kyle 《科学教学研究杂志》1994,31(10):1149-1150

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The effects of baseball bat mass properties on swing mechanics,ground reaction forces,and swing timing     

Walter A. Laughlin  Kyle T. Aune  Alek Z. Diffendaffer 《Sports biomechanics / International Society of Biomechanics in Sports》2016,15(1):36-47

Swing trajectory and ground reaction forces (GRF) of 30 collegiate baseball batters hitting a pitched ball were compared between a standard bat, a bat with extra weight about its barrel, and a bat with extra weight in its handle. It was hypothesised that when compared to a standard bat, only a handle-weighted bat would produce equivalent bat kinematics. It was also hypothesised that hitters would not produce equivalent GRFs for each weighted bat, but would maintain equivalent timing when compared to a standard bat. Data were collected utilising a 500 Hz motion capture system and 1,000 Hz force plate system. Data between bats were considered equivalent when the 95% confidence interval of the difference was contained entirely within ±5% of the standard bat mean value. The handle-weighted bat had equivalent kinematics, whereas the barrel-weighted bat did not. Both weighted bats had equivalent peak GRF variables. Neither weighted bat maintained equivalence in the timing of bat kinematics and some peak GRFs. The ability to maintain swing kinematics with a handle-weighted bat may have implications for swing training and warm-up. However, altered timings of kinematics and kinetics require further research to understand the implications on returning to a conventionally weighted bat.  相似文献   

Differences among fastball,curveball, and change-up pitching biomechanics across various levels of baseball     

Glenn S. Fleisig  Walter A. Laughlin  Kyle T. Aune  E. Lyle Cain  Jeffrey R. Dugas  James R. Andrews 《Sports biomechanics / International Society of Biomechanics in Sports》2016,15(2):128-138

Controversy continues whether curveballs are stressful for young baseball pitchers. Furthermore, it is unproven whether professional baseball pitchers have fewer kinematic differences between fastballs and off-speed pitches than lower level pitchers. Kinematic and kinetic data were measured for 111 healthy baseball pitchers (26 youth, 21 high school, 20 collegiate, 26 minor league, and 18 major league level) throwing fastballs, curveballs, and change-ups in an indoor biomechanics laboratory with a high-speed, automated digitising system. Differences between pitch types and between competition levels were analysed with repeated measures ANOVA. Shoulder and elbow kinetics were greater in fastballs than in change-ups, while curveball kinetics were not different from the other two types of pitches. Kinematic angles at the instant of ball release varied between pitch types, while kinematic angles at the instant of lead foot contact varied between competition levels. There were no significant interactions between pitch type and competition level, meaning that kinetic and kinematic differences between pitch types did not vary by competition level. Like previous investigations, this study did not support the theory that curveballs are relatively more stressful for young pitchers. Although pitchers desire consistent kinematics, there were differences between pitch types, independent of competition level.  相似文献   

John J. Laukaitis. Community Self‐Determination: American Indian Education in Chicago, 1952–2006. Albany: State University of New York Press, 2015. 282 pp. Hardcover $85.00.     

Kyle T. Mays 《History of education quarterly》2016,56(4):669-673

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