Background: The Double Roundhouse Kick (DRK) is one of the major scoring tools and athletes employ the leg of the dominant side (DS) or the non-dominant side (NS) for always attacking in an alternating state. The purpose is to examine the discrepancies in the biomechanical characteristics of the DS and NS of the leg of the DRK skills of sub-elite taekwondo athletes. Methods: Using the Vicon, Kistler, and Daedo brand Electronic Body Protector (EBP), collection of the DRK data (attack time, joint angle, joint angular velocity, joint moment, ground reaction force, etc.) of 12 sub-elite taekwondo athletes (19.6 ± 2.0 yr, 180 ± 7.3 cm, 70 ± 9.8 kg) with the DS leg and NS leg. The measured data analyses via Visual3D, and statistical methods using nonparametric tests paired with samples based on the Wilcoxon signed-rank test (The significance level is set as significant for P<0.05, and very significant for P<0.01). Results: (i) There is no statistically significant discrepancy between the DS and NS at the time of hit (P>0.05) and shift of the center of gravity (P>0.05). (ii) Attacking leg (AL): the maximum knee flexion angle (Knee-MFA) (P<0.05) and the peak linear velocity of attack of the foot in the vertical hitting direction (P<0.01) on the DS was greater than that on the NS during the first hit phase (P1). (iii) Supporting leg (SL): the peak hip extension moment (P<0.05) on the DS was reported to be higher than that of the NS during the second hit phase (P2). (iv) Symmetry Index (SI): In the P1, the vertical ground reaction force (vGRF) of the SL leads to SI = 10.19 %, and in the P2, the vGRF of the SL results in SI = 18.48 %. Conclusions: The DRK requires more and more symmetry between the DS and NS. The Knee-MFA of the AL and the line of attack speed of the foot in the vertical striking direction of the SL exhibited significant discrepancies. The DS has higher striking speed, athletes need to improve the striking speed of the NS leg in training, achieving more scoring opportunities in the game. Both the DS and NS revealed strong symmetry in the peak SI of the ground reaction force of the SL stirrup; however, weak symmetry was attained in the peak SI of the vGRF of the SL landing cushion.
Based on the analysis framework of Ogburn's cultural lag theory and the case study of Y Quanshu(fist)in Fu County of Ningxia,this paper made a field investigation on the crisis of the traditional martial arts and the practice of its improvement.It was found that under the background of modernization transformation,the process of industrialization deconstructed the stable relationship between the traditional martial arts and the rural social structure,and the sense of temporary"loss of domain"led to the decline of the traditional martial arts.However,in the modern existence of Y Quanshu,inheritors made full use of various national policies and realized the cultural expression in the field of"education,socialization and internationalization".According to the research,in the process of modernization,the cultural lagging of the traditional martial arts originated from the asynchronism between the changes of the internal concept and technology and the social development under the external system.The orderly development of Y Quanshu was the result of the parallel type integration of"system,concept and technology".The higher the degree of the parallel type integration between the internal and external elements of the traditional martial arts culture,the smaller the estrangement with the social development and vice versa.Therefore,the modernization of the traditional martial arts needed the coordinated development of the internal and the external factors under the parallel type practice so as to endure.
Sports volunteer service is one of the projects to build China into a sporting nation,and also a part of the Chinese characteristic volunteer service.This study took the integration of sports and education at the grass-roots level volunteer service for sports support education as a case study.The study shows that the strategies of the rural revitalization,building China's strength in education,building healthy China and building a sporting nation are the driving forces for the implementation of volunteer service for sports support education.Secondly,the integration of sports and education at the grassroots level sports volunteer service has formed a practical logic driven by projects,organizations as the main body and content as the core.It has achieved good results in many aspects,such as expressing the good will to promote the healthy growth of the young people,and demonstrating the national capacity to fill the gaps for lack of rural sports resources through good governance in order to achieve the goals of good governance of the country.The basic logic of the sports volunteer service plan consists of action items,action organizations,action content,action effects,and action results,providing fundamental theoretical support for the national and grassroots sports governance.Thirdly,the volunteer service aims to achieve the goals of higher cross departmental administrative efficiency,lower allocation costs of sports professional resources,better national and local multi-level interactive services,and more organizational managers to collaborate in serving the rural youth sports education through the establishment of the national mobilization mechanism,national organizational mechanism,national transformation mechanism,and national development mechanism so as to provide references for further theoretical studies.
Based on the geographical embedding and"off-embedding"theory and the field research of the community sports clubs of Shanghai ZS street,the important functions of geographical community sports on grass-roots social unity and the construction path of grass-roots social unity with geographical community sports as the medium were discussed.The development of industrial and information society led the social members to be increasingly off-embedded from their"nearby"life and established social relations in the broader real world or virtual world,which resulted in the hollowing of the geographical community space,and the geographical community tended to dissociate.With the grass-roots community as the geographical space,geographical community sports became a form of sports participation that was concrete,local,open and life-related.Face-to-face sports participation and interaction among community members could enhance in-depth social communication.Geographical community sports indicated a return to the local life,the construction of an equal,trustworthy and reciprocal relationship within the geographical communication space,and the cultivation of geographical social capital.The development of geographical community sports helped the social members to re-attach importance to their living space nearby,generating the consciousness and emotion of a shared community,constructing a geographical community to enhance the participation of grass-roots society in public affairs and optimizing the governance of grass-roots society.
In the process of Chinese path to modernization,the sports inter-disciplinary integration has undertaken the historical mission of promoting sports science and technology innovation,thus contributing to the building of China into a sporting nation.The study showed that based on the knowledge production mode theory,the sports inter-disciplinary integration process could be divided into four stages:single disciplinary stage,multi-disciplinary stage,cross-disciplinary stage,and trans-disciplinary stage.Moreover,the integration was demonstrated in four aspects:sports sociology and humanities and social sciences,sports education and training science and kinesiology,traditional Chinese sports science and kinesiology,kinesiology and natural sciences.The integration innovation mechanism of sports disciplines was manifested in six aspects:constructing a leading mechanism that served a sporting nation,constructing a sports discipline driving mechanism that was problem oriented,constructing a theoretical oriented empirical research paradigm,constructing a sports discipline organizing mechanism that was trans-disciplinary,constructing a collaborative governance mechanism involving the government,industry,university,research and application,and constructing a diversified and dynamic sports discipline evaluation mechanism.Finally,based on a trans-disciplinary perspective,innovative paradigms for interdisciplinary and integrated research in sports were proposed,a trans-disciplinary thinking pattern in sports was established,a trans-disciplinary integration system in sports was constructed,and a practical path for a tans-disciplinary integration mode was explored.
