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941.
Lara Antunes Ewertton de S. Bezerra Raphael L. Sakugawa 《Sports biomechanics / International Society of Biomechanics in Sports》2018,17(4)
The aim of this study was to investigate the effect of cadence on volume load (VLoad) and muscle activity during agonist –antagonist paired sets (APS) in the lower body. Twelve trained men (24.0 ± 3.3 years; 78.3 ± 9.7 kg; 1.77 ± 0.58 m) volunteered to participate in this study. After the 10 maximum repetition test for leg extension and seated leg curl, participants performed three experimental protocols: first protocol (traditional)—three sets of only leg extension (60 bpm); second protocol (fast cadence)—three sets of leg extension, with each set preceded by one set on the seated leg curl with fast cadence (90 bpm); third protocol (slow cadence)—similar to the second, but seated leg curl with slow cadence (40 bpm). The total number of repetitions, VLoad and the electromyography activity for the vastus lateralis, vastus medialis and rectus femoris muscles were recorded. The VLoad was higher during APS than the traditional method, but the cadence (fast or slow) of antagonist exercise did not influence VLoad. Muscle activity of vastus lateralis was higher during traditional protocol; on the other hand, rectus femoris showed higher activity on APS fast cadence protocol, indicating that APS has a different influence on quadriceps components. 相似文献
942.
Josephine Grigg Eric Haakonssen Evelyne Rathbone Robin Orr Justin W. L. Keogh 《Sports biomechanics / International Society of Biomechanics in Sports》2018,17(3):383-401
The aim of this study was to quantify the validity and intra-tester reliability of a novel method of kinematic measurement. The measurement target was the joint angles of an athlete performing a BMX Supercross (SX) gate start action through the first 1.2 s of movement in situ on a BMX SX ramp using a standard gate start procedure. The method employed GoPro® Hero 4 Silver (GoPro Inc., USA) cameras capturing data at 120 fps 720 p on a ‘normal’ lens setting. Kinovea 0.8.15 (Kinovea.org, France) was used for analysis. Tracking data was exported and angles computed in Matlab (Mathworks®, USA). The gold standard 3D method for joint angle measurement could not safely be employed in this environment, so a rigid angle was used. Validity was measured to be within 2°. Intra-tester reliability was measured by the same tester performing the analysis twice with an average of 55 days between analyses. Intra-tester reliability was high, with an absolute error <6° and <9 frames (0.075 s) across all angles and time points for key positions, respectively. The methodology is valid within 2° and reliable within 6° for the calculation of joint angles in the first ~1.25 s. 相似文献
943.
Maria Inez Angela Z. Ponce de Leon 《Sport in Society》2018,21(9):1302-1318
Football might not be as popular as basketball in the Philippines, but it has a loyal following. In 2012, broadcaster Arnold Clavio claimed that members of the Men’s National Team, the Azkals, were not true Filipinos. Most of the Azkals are children of Filipinos and foreign nationals, and spent their childhood abroad. Clavio’s statement prompted an online writing storm, which the researcher analyzed to examine how Filipinos constructed their identity. Analysis showed that Azkals supporters constructed the Filipino as a ‘citizen of the world’, with a dynamic identity defined by individual emotions. Clavio supporters tended to construct the Filipino as a ‘citizen of the country only’, with an identity fixed by location and acted out in culture. The debate centred on whether Filipino identity could be inherited but changed, or was fixed and immutable. These struggles raise interesting questions on national identity and unity, whether or not football is involved. 相似文献
944.
Annemarie M. H. de Witte Marco J. M. Hoozemans Monique A. M. Berger Rienk M. A. van der Slikke Lucas H. V. van der Woude Dirkjan Veeger 《Journal of sports sciences》2018,36(1):23-32
The aim of this study was to develop and describe a wheelchair mobility performance test in wheelchair basketball and to assess its construct validity and reliability. To mimic mobility performance of wheelchair basketball matches in a standardised manner, a test was designed based on observation of wheelchair basketball matches and expert judgement.Forty-six players performed the test to determine its validity and 23 players performed the test twice for reliability. Independent-samples t-tests were used to assess whether the times needed to complete the test were different for classifications, playing standards and sex. Intraclass correlation coefficients (ICC) were calculated to quantify reliability of performance times.Males performed better than females (P < 0.001, effect size [ES] = ?1.26) and international men performed better than national men (P < 0.001, ES = ?1.62). Performance time of low (≤2.5) and high (≥3.0) classification players was borderline not significant with a moderate ES (P = 0.06, ES = 0.58). The reliability was excellent for overall performance time (ICC = 0.95).These results show that the test can be used as a standardised mobility performance test to validly and reliably assess the capacity in mobility performance of elite wheelchair basketball athletes. Furthermore, the described methodology of development is recommended for use in other sports to develop sport-specific tests. 相似文献
945.
Gustavo Zaccaria Schaun Stephanie Santana Pinto Aline Borges de Carvalho Praia Cristine Lima Alberton 《Journal of sports sciences》2018,36(18):2053-2060
The present study compared the energy expenditure (EE) during and after two water aerobics protocols, high-intensity interval training (HIIT) and moderate continuous training (CONT). A crossover randomized design was employed comprising 11 healthy young women. HIIT consisted of eight 20s bouts at 130% of the cadence associated with the maximal oxygen consumption (measured in the aquatic environment) with 10s passive rest. CONT corresponded to 30 min at a heart rate equivalent to 90–95% of the second ventilatory threshold. EE was measured during and 30 min before and after the protocols and excess post-exercise oxygen consumption (EPOC) was calculated. Total EE during session was higher in CONT (227.62 ± 31.69 kcal) compared to HIIT (39.91 ± 4.24 kcal), while EE per minute was greater in HIIT (9.98 ± 1.06 kcal) than in CONT (7.58 ± 1.07 kcal). Post-exercise EE (64.48 ± 3.50 vs. 63.65 ± 10.39 kcal) and EPOC (22.53 ± 4.98 vs.22.10 ± 8.00 kcal) were not different between HIIT and CONT, respectively. Additionally, oxygen uptake had already returned to baseline fifteen minutes post-exercise. These suggest that a water aerobics CONT session results in post-exercise EE and EPOC comparable to HIIT despite the latter supramaximal nature. Still, CONT results in higher total EE. 相似文献
946.
Paulo Vitor da Silva Romero Débora Alves Guariglia Francielli Ferreira Da Rocha Caroline de Carvalho Picoli Gustavo Renan Gilio Gabriel Sergio Fabricio 《Journal of sports sciences》2018,36(14):1578-1585
The present study aimed to determine the effects of physical training performed by parents on mice offspring adiposity. Male and female parents underwent an aerobic training protocol for 7 weeks. The trained and sedentary parents were allowed to mate and the resultant offspring divided in: S (Offspring from Sedentary Parents), T (Offspring from Trained Parents), ST (Offspring from Sedentary Father and Trained Mother) and TS (Offspring from Trained Father and Sedentary Mother). After weaning, offspring was euthanized, blood collected and samples of mesenteric and inguinal fat pads used to isolate adipocytes for morphologic and histological analyses. Lee index, mesenteric fat pad, sum of visceral fat and total fat weight of female T was reduced in comparison to the other groups (p < 0.05). Periepididymal and sum of visceral fat in male T group was also reduced when compared to the other groups (p < 0.05). The diameter of mesenteric and inguinal adipocytes of T group was smaller compared to all groups comparisons for both sexes (p < 0.05). In summary, exercise training performed by parents reduced visceral offspring adiposity, the diameter of subcutaneous adipocytes and improved metabolic parameters associated to metabolic syndrome. 相似文献
947.
Karina L. R. Canabrava Fernanda R. Faria Jorge R. P. de Lima Dartagnan P. Guedes Paulo R. S. Amorim 《Research quarterly for exercise and sport》2018,89(1):47-56
Purpose: This study aimed to compare the energy expenditure and intensity of active video games to that of treadmill walking in children and adolescents. Method: Seventy-two boys and girls (aged 8–13 years) were recruited from local public schools. Energy expenditure and heart rate were measured during rest, during 3-km/hr, 4-km/hr, and 5-km/hr walks, and during active games (Adventure, Boxing I, Boxing II, and Dance). During walking and active games, we also assessed physical activity using an accelerometer. Results: The energy expenditure of the active games Adventure, Boxing I, Boxing II, and Dance was similar to that of treadmill walking at 5 km/hr in boys and girls. Heart rate was significantly higher for the game Adventure compared with walking at 3 km/hr, 4 km/hr, and 5 km/hr and the game Dance in both genders. The heart rate of girls during the games Adventure and Dance was significantly higher compared with boys. There was a statistically significant difference (p < .05, with an effect size ranging from 0.40 to 3.54) in the counts·min?1, measured through accelerometry, between activities. Conclusion: XBOX 360 Kinect games provide energy expenditure and physical activity of moderate intensity for both genders. The use of active video games can be an interesting alternative to increase physical activity levels. 相似文献
948.
949.
Query Expansion is commonly used in Information Retrieval to overcome vocabulary mismatch issues, such as synonymy between
the original query terms and a relevant document. In general, query expansion experiments exhibit mixed results. Overall TREC
Genomics Track results are also mixed; however, results from the top performing systems provide strong evidence supporting
the need for expansion. In this paper, we examine the conditions necessary for optimal query expansion performance with respect
to two system design issues: IR framework and knowledge source used for expansion. We present a query expansion framework
that improves Okapi baseline passage MAP performance by 185%. Using this framework, we compare and contrast the effectiveness
of a variety of biomedical knowledge sources used by TREC 2006 Genomics Track participants for expansion. Based on the outcome
of these experiments, we discuss the success factors required for effective query expansion with respect to various sources
of term expansion, such as corpus-based cooccurrence statistics, pseudo-relevance feedback methods, and domain-specific and
domain-independent ontologies and databases. Our results show that choice of document ranking algorithm is the most important
factor affecting retrieval performance on this dataset. In addition, when an appropriate ranking algorithm is used, we find
that query expansion with domain-specific knowledge sources provides an equally substantive gain in performance over a baseline
system.
相似文献
Nicola StokesEmail: Email: |
950.
Cara J. Alexander Weronika M. Crescini Justin E. Juskewitch Nirusha Lachman Wojciech Pawlina 《Anatomical sciences education》2009,2(4):160-166
The goals of our study were to determine the predictive value and usability of an audience response system (ARS) as a knowledge assessment tool in an undergraduate medical curriculum. Over a three year period (2006–2008), data were collected from first year didactic blocks in Genetics/Histology and Anatomy/Radiology (n = 42–50 per class). During each block, students answered clinically oriented multiple choice questions using the ARS. Students' performances were recorded and cumulative ARS scores were compared with final examination performances. Correlation coefficients between these variables were calculated to assess the existence and direction of an association between ARS and final examination score. If associations existed, univariate models were then constructed using ARS as a predictor of final examination score. Student and faculty perception of ARS difficulty, usefulness, effect on performance, and preferred use were evaluated using a questionnaire. There was a statistically significant positive correlation between ARS and final examination scores in all didactic blocks and predictive univariate models were constructed for each relationship (all P < 0.0001). Students and faculty agreed that ARS was easy to use and a reliable tool for providing real‐time feedback that improved their performance and participation. In conclusion, we found ARS to be an effective assessment tool benefiting the faculty and the students in a curriculum focused on interaction and self‐directed learning. Anat Sci Educ 2:160–166. © 2009 American Association of Anatomists. 相似文献