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1.
Abstract

This 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   
2.
李俊  梁恒 《当代体育科技》2020,(11):216-217
对以体育竞赛为核心内容的体育赛事立法是国际通行做法,目的就是要在有关体育赛事法律的保障下使得体育竞赛的各事项正常有序进行。体育赛事立法效力就是指拥有立法权的部门或依法受权立法部门针对体育赛事运行阶段所制定、修改、补充和废止一些规范性文件,在具体实施过程中所产生的效果和作用力。体育赛事运行涉及的人多、事杂、域广,其聚集性、综合性和体验性等特点决定了体育赛事立法效力具有时空相对聚集、立法层级较低、对象范围有限、公共权利保障性与包容性兼备等特殊性;影响其立法效力的因素主要有从体育赛事运行的秩序化客观需求出发的现实性、立法活动的合法性、立法程序的有效性、法律位阶的层级性及立法内容的专业性。  相似文献   
3.
Rater training is an important part of developing and conducting large‐scale constructed‐response assessments. As part of this process, candidate raters have to pass a certification test to confirm that they are able to score consistently and accurately before they begin scoring operationally. Moreover, many assessment programs require raters to pass a calibration test before every scoring shift. To support the high‐stakes decisions made on the basis of rater certification tests, a psychometric approach for their development, analysis, and use is proposed. The circumstances and uses of these tests suggest that they are expected to have relatively low reliability. This expectation is supported by empirical data. Implications for the development and use of these tests to ensure their quality are discussed.  相似文献   
4.
Professor Gordon argues for a significant reorientation in the focus and impact of assessment in education. For the types of assessment activities that he advocates to prosper and positively impact education, serious attention must be paid to two important topics: (1) the conceptual underpinnings of the assessment practices we develop and use to support learning and instruction, and (2) the arguments and evidence we establish for their validity given the intended interpretive use. Such a focus highlights fundamental concepts that have long existed in the broader assessment literature – carefully defining and operationalizing our constructs and then validating the assessments of those constructs. What differs now are the conceptual frameworks, briefly outlined here, that can and must be used to guide both aspects of such work.  相似文献   
5.
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   
6.
This study examined the relationship between sit-to-stand (STS) power and physical function in adults with severe obesity. Thirty-eight adults (age: 44 ± 12 years; body mass index [BMI]: 45.2 ± 7.8 kg/m2) completed evaluations of STS power, strength and functional performance. STS power was measured with a wearable inertial sensor, strength was assessed with the isometric mid-thigh pull, and function was measured with the timed up-and-go (TUG), six-minute walk test (6MWT) and 30-s chair STS. Power and strength (normalised to body mass) entered regression models in addition to age, gender, BMI and physical activity (daily step count). Power displayed large univariate associations with TUG (r = 0.50) and 30-s chair STS (r = 0.67), and a moderate association with 6MWT (r = 0.49). Forward stepwise regression revealed that power independently contributed to TUG (β = ?0.40, p = 0.010), 30-s chair STS (β = 0.67, p < 0.001) and 6MWT performance (β = 0.27, p = 0.007). Power also appeared to be a superior determinant of function compared with strength. Power generated via the STS transfer largely underpins the ability to perform functional tasks in adults with severe obesity, although intervention studies are required to investigate a potentially causal relationship.  相似文献   
7.
Recent advances have enabled diagnostic classification models (DCMs) to accommodate longitudinal data. These longitudinal DCMs were developed to study how examinees change, or transition, between different attribute mastery statuses over time. This study examines using longitudinal DCMs as an approach to assessing growth and serves three purposes: (1) to define and evaluate two reliability measures to be used in the application of longitudinal DCMs; (2) through simulation, demonstrate that longitudinal DCM growth estimates have increased reliability compared to longitudinal item response theory models; and (3) through an empirical analysis, illustrate the practical and interpretive benefits of longitudinal DCMs. A discussion describes how longitudinal DCMs can be used as practical and reliable psychometric models when categorical and criterion‐referenced interpretations of growth are desired.  相似文献   
8.
Muscle imbalance and deficit are key parameters for guiding rehabilitation and sports sessions and avoiding injuries. However, the high cost and non-portable nature of most instruments employed for muscle strength assessment frequently hamper an affordable evaluation in field conditions. This study evaluated the validity and reliability of a low-cost digital dynamometer to assess the maximal isometric strength of upper limb muscles. Fourteen physically active volunteers performed the main movements of the upper limb at maximal isometric strength: flexion-extension, internal-external rotation and abduction-adduction of the shoulder; and flexion-extension of both elbow and wrist. Validity was examined by comparing the strength values from the low-cost digital dynamometer and those measured by an isokinetic dynamometer, assumed as the gold standard. The correlation between both devices was perfect (r > 0.913), while Bland-Altman plots showed absolute agreement between both devices, the maximum range of the values of bias was ?0.99–1.00 N in wrist extension. Inter-tester and intra-tester reliability were excellent for all movements (ICC ≥ 0.855). The low-cost digital dynamometer showed strong validity and excellent reliability in assessing maximal isometric strength during the main movements of the upper limb. Professionals may use it for an affordable isometric muscle strength assessment in field situations.  相似文献   
9.
文章采用文献资料法、专家访谈法、视频分析法和数理统计法,对李大勋在重大国际赛事中的交手回合、基本技术、组合技术的应用频数以及成功率等指标进行统计分析。根据2018-2019年度世界跆拳道联盟公布的最新奥运积分显示,李大勋拥有605.94个奥运积分且高于第二名将近300余分,目前世界排名第一,其技战术风格具有一定的代表性。结果显示:李大勋在比赛中习惯采用前腿侧踢与前腿横踢技术进行主动进攻、控制距离、防守破坏、封堵迎击;利用后腿横踢技术进行补充击打;灵活使用中变中、中变高等变线技术突破对手;新规则后近身贴靠时攻防转换技战术变化多样,"推+踢"技术运用巧妙,增加了其得分手段。分析认为,在实施新规则的比赛中李大勋结合判罚尺度与分值的变化,优化了进攻方式,增加了得分手段,提高了时局节奏,同时反映出现阶段跆拳道项目技战术发展趋势。  相似文献   
10.
Self‐report inventories are commonly administered to measure social‐emotional learning competencies related to college and career readiness. Inattentive responding can negatively impact the validity of interpreting individual results and the accuracy of construct validity evidence. This study applied nine methods of detecting insufficient effort responding (IER) to a social‐emotional learning assessment. Individual methods identified between 0.9% and 20.3% of respondents as potentially exhibiting IER. Removing flagged respondents from the data resulted in negligible or small improvements in criterion‐related validity, coefficient alpha, concurrent validity, and confirmatory factor analysis model‐data fit. Implications for future validity studies and the operational use of IER detection for social–emotional learning assessments are discussed.  相似文献   
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