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Aurélio Faria Ronaldo Gabriel Helena Moreira Tanya Camacho Rui Brás Massimiliano Ditroilo 《European Journal of Sport Science》2018,18(4):483-490
Purpose: The main purpose of this study was to investigate the influence of fatigue on musculoarticular stiffness (MAS) of the ankle joint across sexes. Methods: Twenty-seven males and 26 females participated in the study. After baseline assessment of MAS and related variables, localised fatigue was induced in triceps surae using the standing heel-rise test during which the subjects were instructed to lift and drop the heel at a frequency of 0.5?Hz. When subjects were unable to continue due to exhaustion the test was terminated and another MAS test was performed soon after. Results: Significant higher triceps surae MAS was found in men compared to women (p?p??1 and from 14.5 to 13.9?KN?m?1 in men and women, respectively. Percentage changes revealed, however, that in relative terms the changes in all the variables evaluated were similar (p?>?.01) between sexes, with MAS less than 5%. Conclusion: Despite the sex-related differences at baseline, fatigue seems to affect biomechanical properties of the ankle joint similarly in men and women. 相似文献
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Irineu Loturco Sophia Nimphius Ronaldo Kobal Altamiro Bottino Vinicius Zanetti Lucas A. Pereira Ian Jeffreys 《Sportwissenschaft》2018,48(2):228-234
Change-of-direction (COD) ability is an essential physical component for soccer. This study examined the relationships between conventional speed–power assessments and COD performance in elite young soccer players. Twenty-five under-20 male players from the same club (age: 17.6?±?0.8 years, height: 178.1?±?6.7?cm, body mass [BM]: 72.2?±?7.9?kg) performed sprint speed tests, vertical jumps, loaded jump squats, half squats, and Zigzag COD assessments. Moreover, the COD deficit was calculated as the difference between 20-m sprint velocity and Zigzag COD test velocity. A Pearson correlation analysis was used to determine the correlations between Zigzag COD performance and COD deficit with speed and power outputs. Although no significant relationships between speed–power variables and COD ability were present, there were still strong positive correlations between traditional neuromechanical measures and COD deficit. Briefly, it seems that higher performances in speed and power tests are not necessarily related to better performances in specific COD maneuvers. Therefore, it is recommended that coaches and technical staff include specific COD drills in soccer player routines to optimize the transference from speed and power capacities to specific COD performance. 相似文献
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Saulo Gil Irineu Loturco Valmor Tricoli Carlos Ugrinowitsch Ronaldo Kobal Cesar Cavinato Cal Abad 《Sports biomechanics / International Society of Biomechanics in Sports》2013,12(3):340-350
Tensiomyography has been suggested as an indirect marker of muscle stiffness, which is associated with strength/power performance. Therefore, it is reasonable to suggest that tensiomyography parameters could be associated with power-related motor tasks. The purpose of this study was to investigate the association between tensiomyography parameters (from rectus and biceps femoris) and jumping and sprinting abilities in elite soccer players. In addition, we used tensiomyography parameters to compare the lateral symmetry between dominant and non-dominant legs. Twenty elite soccer players (age: 23.3 ± 4.8 years; height: 183.5 ± 6.6 cm; weight: 77.8 ± 7.5 kg) volunteered to participate in the study. Significant moderate negative correlations between biceps femoris displacement and contact time (r = –0.5, p = 0.03), rectus femoris displacement and contact time (r = –0.51, p = 0.02), and a significant moderate correlation between biceps femoris displacement and reactive strength index (r = 0.5, p = 0.03) were found. There were no correlations between tensiomyography parameters and power-related motor tasks. In addition, no differences in tensiomyography parameters between dominant and non-dominant legs were found. Our data suggest that tensiomyography parameters are not associated with power-related motor tasks performance in elite soccer players. 相似文献
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John W. Landon Susannah Harris Stone John Fell Herbert Marshall John Kobal V.A. Wilson 《Communication Booknotes Quarterly》2013,44(7):70-71
John W. Landon BEYOND THE MIGHTY WURLITZER: THE HISTORY OF THE THEATRE PIPE ORGAN (Westport, Connecticut: Greenwood Press,,1983—$29.95). Susannah Harris Stone THE OAKLAND PARAMOUNT (Berkeley California: Lancaster-Miller Publishers, 1981—$11.95). John Fell FILM BEFORE GRIFFTTH (Berkeley, California: University of California Press, 1984—$24.50/$10.95). Herbert Marshall MASTERS OF THE SOVIET CINEMA: CRIPPLED CREATIVE BIOGRAPHIES (London: Routledge 8 Kegan Paul, 1983—$29.95). John Kobal and V.A. Wilson FOYER PLEASURE: THE GOLDEN AGE OF CINEMA LOBBY CARDS (New York: Deliliah Books, 1983—$12.95). Don Graham COWBOYS AND CADILLACS: HOW HOLLYWOOD LOOKS AT TEXAS (Texas Monthly Press, P.O. Box 1569, Austin, Texas 78767—$10.95). 相似文献
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Firstly, inspired by Le Goff and Truong (Une histoire du corps au Moyen Âge), Richard Sennett (Flesh and Stone) and Michel Maffesoli (Le Rythme de Vie), we have outlined some considerations for the organization of the history of the body in Brazilian football. In the second topic, we review studies that examine the convergence between football and advertising. This theoretical background will link to the subsequent analysis of 11 advertisements of well-known brands in which Brazilian football athlete, Neymar, appears as the poster boy. It is said that in football, especially in the first half of the twentieth century, there was certain prejudice against blacks and biracial players (until today Europe reports cases of racism); in advertising, these groups were kept from certain positions also. In short, Neymar takes part in a scenario of identity crisis as an icon able to instigate criticism as well as praise. His public image is permeated by the youthful desire to see himself represented. 相似文献
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Irineu Loturco Lucas Adriano Pereira Cesar Cavinato Cal Abad Facundo Tabares José Eduardo Moraes Ronaldo Kobal 《Journal of sports sciences》2017,35(8):734-741
This study aimed at testing whether there are mean propulsive velocities (MPVs) capable of maximising the mean propulsive power (MPP) during the execution of bench press (BP), bench throw (BT), half squat (HS) and jump squat (JS). Additionally, we assessed the differences in MPP/MPV between ballistic and traditional exercises. Seventeen male rugby sevens players performed MPP tests in BP, BT, HS and JS and maximum isometric force (MIF) tests in HS and BP. The JS presented higher MPP (977.4 ± 156.2 W) than the HS (897.9 ± 157.7 W) (P < 0.05); the BP (743.4 ± 100.1 W) presented higher MPP than the BT (697.8 ± 70.4 W) (P < 0.05). Ballistic exercises presented higher optimum MPV (JS = 1.02 ± 0.07 m·s?1; BT = 1.67 ± 0.15 m·s?1) than traditional exercises (HS = 0.93 ± 0.08 m·s?1; BP = 1.40 ± 0.13 m·s?1) (P < 0.05). The optimum MPP in the JS, BT, HS and BP occurred at 28.2 ± 5.79, 23.3 ± 4.24, 32.4 ± 9.46 and 27.7 ± 5.33% of the MIF, respectively. The coefficient of variation (CV) of MPV at optimum MPP ranged from 7.4% to 9.7%, while the CV of %MIF ranged from 18.2% to 29.2%. The MPV is a more precise indicator of the optimum loads than the percentages of MIF due to its low inter-subject variability as expressed by CV. Therefore, MPV can be used to determine the optimum power load in the four investigated exercises. 相似文献
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Ronaldo Helal 《Soccer & Society》2014,15(1):132-146
This essay analyses the media narrative in the coverage of the Brazilian team during the 2002 World Cup. The corpus of our work is concentrated on the sports supplements of Jornal do Brasil during the 2002 World Cup from two days before the event until two days after its end, reaching the total of 32 supplements. We focus on the hypothesis that the qualification ‘Brazil: the soccer country’, usually even more intense and singular during this worldwide event, has been decreasing and the journalistic narratives about the Brazilian soccer team do not approach soccer homogeneously as a metonym for the nation. The reflection about the role of the sports press as cultural builder is fundamental to observe how newspapers confirm and construct mythologies and identitary discourses, in spite of the journalistic objectivity, one of the pillars of the profession. 相似文献
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Irineu Loturco Ian Jeffreys César C. Cal Abad Ronaldo Kobal Vinicius Zanetti Lucas A. Pereira 《Journal of sports sciences》2020,38(11-12):1279-1285
ABSTRACT This study examined the age-specific development of vertical jump height, straight and change-of-direction (COD) speed, and COD deficit in one-hundred and eighty-two elite soccer players from different age-categories (U15, U17, U20, and Senior). All participants were players of two distinct clubs and were undertaking different training routines, as planned by their technical staff members. For this purpose, the soccer players performed: (1) squat and countermovement jumps; (2) a maximal 20-m linear sprint speed test, and (3) the Zigzag COD test. The magnitude-based inference approach and standardized differences were used to compare the age-groups. Sprint speed at longer distances (20-m) increased progressively across the age-ranges. In contrast, speed and acceleration performances at shorter distances (5-m) were better in U15 than in the other age-categories. The COD speed did not change throughout the younger categories but presented a meaningful decrease in the Senior category. Surprisingly, despite the progressive increase in volume and intensity of neuromuscular training from younger to older categories, the COD deficit presented a gradual increase across the age-groups. It is possible that simple modulation of the strength-power training program during the maturation process is not sufficient to produce faster adult players with enhanced ability to change direction. Therefore, coaches are strongly encouraged to implement specific COD training practices to tolerate braking at increasing running speeds and appropriate volume and intensity of soccer specific training throughout the players’ specialization process. 相似文献
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Irineu Loturco Lucas A. Pereira Ronaldo Kobal Michael R. McGuigan 《Journal of sports sciences》2019,37(3):277-284
This study aimed to compare the power production in traditional bench-press (TBP) and ballistic bench-throw (BBT) exercises. Furthermore, we assessed the differences in velocity, force, and power outputs between TBP and BBT. Finally, we tested the differences between the loads used to optimize power (optimum power load; OPL) in both exercises, using three distinct power-variables: mean power (MP), mean propulsive power (MPP), and peak power (PP). Sixty athletes from different sports were divided into two groups, according to their training characteristics: hypertrophy-based trained athletes (HTA), thirty-one athletes performing hypertrophy training programmes for (at least) 12-weeks; and power-based trained athletes (PTA), twenty-nine athletes performing power-oriented training sessions for (at least) 12-weeks. Magnitude-based inferences were used to test for differences between groups. Independent of the variable analyzed (MP, MPP, or PP), the PTA produced greater power values in BBT, whereas the HTA generated higher outputs during TBP. The OPL in the HTA was likely heavier in TBP than in BBT, whereas no differences related to this variable were found in the PTA. Despite the apparent superiority of ballistics to produce power, it seems that in elite athletes, the strength-power training routine might affect the ability to apply high forces at very-high velocities. 相似文献