New curve sprint test for soccer players: Reliability and relationship with linear sprint     

Alberto Fílter  Jesús Olivares  Alfredo Santalla  Fabio Y. Nakamura  Irineu Loturco  Bernardo Requena 《Journal of sports sciences》2020,38(11-12):1320-1325

ABSTRACT

The speed performance is involved not only in linear sprints, but also in a wide spectrum of multi-directional movements, such as curve sprinting. Curved sprint can be defined as sprint with gradual and continuous change of direction (COD). Although ~85% of the actions performed at maximum velocity in a professional soccer league are curvilinear sprints, there is not any specific test to assess this ability. This study aimed to analyse the reliability of a new curve sprint test, and compare its results with those obtained by soccer players in linear sprint. Forty experienced soccer players performed 3 attempts of curve sprint (using the penalty arc) to right and left side (17 m), and 3 linear sprints (17 m) in two different days. The ICCs (inter-session reliability) were 0.93 for sprint curve right side (CSRS) and 0.89 for sprint curve left side (CSLS), considered “acceptable”. The CVs (intra-session reliability) were 0.87% in CSRS and 1.15% in CSLS. The coefficient of determination (R²) between linear and curve sprinting was ~35%. The association between curve sides was “very large” (r = 0.878; p < 0.01). In summary, we showed that “curve sprint test” is highly reliable, and that curvilinear and linear sprints are different and independent actions.  相似文献   

Comparison of Haptic and Biometric Properties,Bacterial Load,and Student Perception of Fixative Solutions: Formaldehyde Versus Chilean Conservative Fixative Solution with and without Formaldehyde in Pig Kidneys     

Marianne Skopnik-Chicago  Katherine Poblete-Cordero  Natali Zamora  Roberto Bastías  Pablo A. Lizana 《Anatomical sciences education》2021,14(6):836-846

One of the most widely used solutions to fix and preserve organic tissues is formaldehyde, despite reservations regarding its toxicity and the fact that formaldehyde-embalmed bodies lose their original characteristics. Anatomy laboratories have been replacing formaldehyde with solutions that retain the characteristics of fresh tissue. For this purpose, alternative solutions with a very low concentration of formaldehyde or without any formaldehyde have been analyzed. The objective of this study was to compare biometry, coloration, haptic properties, and bacterial load on animal specimens (pig kidneys) embalmed with formaldehyde, and with Chilean Conservative Fixative Solution with and without formaldehyde (formaldehyde chCFS and formaldehyde-free chCFS). Also, the perception of health and biological science students toward specimens treated with different solutions was assessed. The results indicated that there were no significant differences in specimens’ retraction, or bacterial load. Students showed a preference for organs embalmed in formaldehyde chCFS and formaldehyde-free chCFS; indicating that with these treatments they could better visualize structures and that the prosections had greater flexibility and the colors were more similar to those of fresh tissue. Additionally, students recommended the material embalmed in formaldehyde chCFS and formaldehyde-free chCFS for anatomy learning. In contrast, students indicated that formaldehyde-fixation negatively affected their practical experience. In conclusion, embalming with formaldehyde chCFS or formaldehyde-free chCFS provides an advantageous practical experience over the use of formaldehyde and may be an alternative to replace the use of formaldehyde in anatomy laboratories.  相似文献   

Application of velocity loss thresholds during free-weight resistance training: Responses and reproducibility of perceptual,metabolic, and neuromuscular outcomes     

Jonathon Weakley  Shaun McLaren  Carlos Ramirez-Lopez  Amador García-Ramos  Nick Dalton-Barron  Harry Banyard 《Journal of sports sciences》2020,38(5):477-485

ABSTRACT

The aim of this study was to investigate the differences and long-term reliability in perceptual, metabolic, and neuromuscular responses to velocity loss resistance training protocols. Using a repeated, counterbalanced, crossover design, twelve team-sport athletes completed 5-sets of barbell back-squats at a load corresponding to a mean concentric velocity of ~0.70 m·s^?1. On different days, repetitions were performed until a 10%, 20% or 30% velocity loss was attained, with outcome measures collected after each set. Sessions were repeated after four-weeks. There were substantial between-protocol differences in post-set differential ratings of perceived exertion (dRPE, i.e., breathlessness and leg muscles, AU) and blood lactate concentration (B[La], mmol·L^?1), such that 30%>20%>10% by small to large magnitudes. Differences in post-set countermovement jump (CMJ) variables were small for most variables, such that 30%<20%<10%. Standard deviations representing four-week variability of post-set responses to each protocol were: dRPE, 8–11; B[La], 0.8–1.0; CMJ height, 1.6–2.0; CMJ PPO, 1.0–1.8; CMJ PCV, 0.04–0.06; CMJ 100ms-Impulse, 5.7–11.9. Velocity loss thresholds control the magnitude of perceptual, metabolic, and neuromuscular responses to resistance training. For practitioners wanting to reliably prescribe training that can induce a given perceptual, metabolic, or neuromuscular response, it is strongly advised that velocity-based thresholds are implemented.  相似文献   

The Quality and Readability of English Wikipedia Anatomy Articles     

Athikhun Suwannakhan  Daniel Casanova-Martínez  Laphatrada Yurasakpong  Punchalee Montriwat  Krai Meemon  Taweetham Limpanuparb 《Anatomical sciences education》2020,13(4):475-487

Forty anatomy articles were sampled from English Wikipedia and assessed quantitatively and qualitatively. Quantitatively, each article’s edit history was analyzed by Wikipedia X-tools, references and media were counted manually, and two readability indices were used to evaluate article readability. This analysis revealed that each article was updated 8.3 ± 6.8 times per month, and referenced with 33.5 ± 24.3 sources, such as journal articles and textbooks. Each article contained on average 14.0 ± 7.6 media items. The readability indices including: (1) Flesch–Kincaid Grade Level Readability Test and (2) Flesch Reading Ease Readability Formula demonstrated that the articles had low readability and were more appropriate for college students and above. Qualitatively, the sampled articles were evaluated by experts using a modified DISCERN survey. According to the modified DISCERN, 13 articles (32.5%), 24 articles (60%), 3 articles (7.5%), were rated as “good,” “moderate,” and “poor,” respectively. There were positive correlations between the DISCERN score and the number of edits (r = 0.537), number of editors (r = 0.560), and article length (r = 0.536). Strengths reported by the panel included completeness and coverage in 11 articles (27.5%), anatomical details in 10 articles (25%), and clinical details in 5 articles (12.5%). The panel also noted areas which could be improved, such as providing missing information in 28 articles (70%), inaccuracies in 10 articles (25%), and lack or poor use of images in 17 articles (42.5%). In conclusion, this study revealed that many Wikipedia anatomy articles were difficult to read. Each article’s quality was dependent on edit frequency and article length. Learners and students should be cautious when using Wikipedia articles for anatomy education due to these limitations.  相似文献   

The Rise in Single-Mother Families and Children’s Cognitive Development: Evidence From Three British Birth Cohorts     

Susan Harkness  Paul Gregg  Mariña Fernández-Salgado 《Child development》2020,91(5):1762-1785

This article assessed changes in the association between single motherhood and children’s verbal cognitive ability at age-11 using data from three cohorts of British children, born in 1958 (n = 10,675), 1970 (n = 8,933) and 2000 (n = 9,989), and mediation analysis. Consistent with previous studies, direct effects were small and insignificant. For those born in 1958 and 1970 indirect effects, operating through reduced economic and parental resources, were associated with −.107-SD to −.156-SD lower attainment. Differences between the two cohorts, and by children’s age when parents separated, were insignificant. For the 2000 cohort, effect sizes for children born to single mothers did not change significantly (−.112-SD) but attenuated for children whose parents separated in early childhood (−.076-SD) or while of school age (−.054-SD).  相似文献   

Promoting a participatory convergence in a Spanish context: an inter-university action research project using visual narrative     

Elia Fernández-Díaz  Carlos Rodríguez-Hoyos  Adelina Calvo Salvador  Gloria Braga Blanco  Lorea Fernández-Olaskoaga  Prudencia Gutiérrez-Esteban 《Educational Action Research》2019,27(3):362-378

ABSTRACT

This article focuses on the deconstruction of an inter-university action research project that has allowed us to rethink our teaching and research, questioning the social, political and ethical dimensions of the university. Following the pre-assembly proposal to promote participatory convergence, organized within the framework of the 1^st Global Assembly for Knowledge Democracy (2017), an action research process was implemented in order to generate systematic inquiry around the current situation of the university and the need to act and rethink our commitment to promoting changes in this context. We have reflected on the meaning of democratization, rethinking the pedagogical relationship with our students and how we critically commit them to promote activism. We generated an environment where we look for the meaning of our practices by means of a visual narrative which has enabled us to weave and identify our own biography and become aware of where we are and why we act in one way or another. We have also focused on the search for the meaning of our actions in relation to the community we belong to and how to deal with the challenges of social justice, encouraging collaboration with other networks in a wider inter-university framework.  相似文献   

The role of task and ego-oriented climate in explaining students’ bright and dark motivational experiences in Physical Education     

Luis García-González  Javier Sevil-Serrano  Angel Abós  Nathalie Aelterman  Leen Haerens 《Physical Education & Sport Pedagogy》2019,24(4):344-358

Background: A distinction is made in Achievement Goal Theory (AGT) between task-oriented (i.e. effort, intra-individual progress, and self-comparison) and ego-oriented (i.e. inter-individual progress and normative comparison) climates. Combining insights from AGT and Self-Determination Theory (SDT), studies in the PE context have shown that a task-oriented climate positively relates to need satisfaction, although the findings regarding the motivating role of an ego-oriented climate are inconsistent. Moreover, little is known about the role of task- or ego-oriented climates in explaining experiences of basic psychological need frustration.

Purpose: Grounded in AGT and SDT, the aim of the present study was to examine if experiences of basic psychological need satisfaction and need frustration can explain why task- and ego-oriented climates elicit positive and negative motivational outcomes in PE, respectively.

Research design: Cross-sectional study.

Method: A sample of 524 secondary school students (51.1% boys, M_age?=?14.51; SD?=?1.81) from five different secondary schools participated in this study. Students reported on their perceptions of task- and ego-oriented climates, motivational regulations, basic psychological need satisfaction, and need frustration, as well as positive and negative outcomes in PE. Structural equation modeling was used to investigate our objective.

Results: We found that a task-oriented climate had a strong and positive relationship with basic psychological need satisfaction, eliciting a bright pathway to autonomous motivation and affective attitude. An ego-oriented climate was positively related to basic psychological need frustration, eliciting a dark pathway to amotivation and boredom. A negative cross-path from task-oriented climate to basic psychological need frustration was also found, while no significant cross-paths were found from ego-oriented climate to basic psychological need satisfaction.

Conclusions: This study provides a better understanding of the mechanisms that explain why task- and ego-oriented climates shape students’ motivational experiences in PE lessons. It is suggested that a task-oriented climate elicits a bright pathway towards more optimal functioning, because it fosters experiences of need satisfaction and buffers against experiences of need frustration. In contrast, an ego-oriented climate is primarily positively related to feelings of need frustration and negative motivational outcomes. Practical implications for PE teacher training are discussed.  相似文献   

Recording the war effort: immigrant communities in Latin America and the memory of the Great War     

María Inés Tato 《档案与原稿》2020,48(2):200-215

ABSTRACT

This paper aims to analyse the initiatives undertaken by some immigrant communities residing in Latin America to record their mobilisation around the First World War. After the armistice, European communities in Argentina, Bolivia, Brazil, Chile, Mexico, Paraguay, Peru, Uruguay and other countries gathered detailed information about their activities during the conflict, published as profusely illustrated books of remembrance, offered to their governments as proof of their loyalty. The article intends to establish the peculiar nature of these publications as records of the war effort, and analyse the agents and processes of their elaboration, and their role as commemorative but also as archival documents.  相似文献   

Visual function,performance, and processing of basketball players vs. sedentary individuals     

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   

Cardiorespiratory and perceptual responses of two interval training and a continuous training protocol in healthy young men     

João Pedro Araújo Naves  Ana Cristina Silva Rebelo  Lucas Raphael Bento E Silva  Maria Sebastiana Silva  Rodrigo Ramirez-Campillo  Robinson Ramírez-Vélez 《European Journal of Sport Science》2019,19(5):653-660

High Intensity Interval Training (HIIT) can be performed with different effort to rest time-configurations, and this can largely influence training responses. The purpose of the study was to compare the acute physiological responses of two HIIT and one moderate intensity continuous training (MICT) protocol in young men. A randomised cross-over study with 10 men [age, 28.3?±?5.5years; weight, 77.3?±?9.3?kg; height, 1.8?±?0.1?m; peak oxygen consumption (VO₂peak), 44?±?11?mL.kg^?1.min^?1]. Participants performed a cardiorespiratory test on a treadmill to assess VO₂peak, velocity associated with VO₂peak (vVO₂peak), peak heart rate (HRpeak) and perceived exertion (RPE). Then participants performed three protocols equated by distance: Short HIIT (29 bouts of 30s at vVO₂peak, interspersed by 30s of passive recovery, 29?min in total), Long HIIT (3 bouts of 4?min at 90% of vVO₂peak, interspersed by 3?min of recovery at 60% of vVO₂peak, 21?min in total) and MICT (21?min at 70% of vVO₂peak). The protocols were performed in a randomised order with ≥48 h between them. VO₂, HRpeak and RPE were compared. VO₂peak in Long HIIT was significantly higher than Short HIIT and MICT (43?±?11 vs 32?±?8 and 37?±?8?mL.kg^?1.min^?1, respectively, P?P?P?2, HR and RPE than Short HIIT and MICT, suggesting a higher demand on the cardiorespiratory system. Short HIIT and MICT presented similar physiologic and perceptual responses, despite Short HIIT being performed at higher velocities.  相似文献