Biomechanics of judo backward breakfall for different throwing techniques in novice judokas     

Sentaro Koshida  Takanori Ishii  Tadamitsu Matsuda  Toshihiko Hashimoto 《European Journal of Sport Science》2017,17(4):417-424

It is generally accepted that proper learning of the breakfall technique during early judo training is essential for attenuating the risk of judo-related head injury. Therefore, it is critical to understand the kinematics and head injury risks of breakfall motion to design a more safe and effective judo teaching paradigm that results in reduction of injury risk. We aimed to investigate the biomechanics of judo backward breakfalls by comparing osoto-gari and ouchi-gari in novice judokas. Twelve male novice judokas (age: 21.3 years, SD?=?0.6 years; height: 1.74?m, SD?=?0.04?m; body weight: 71.3, SD?=?6.4?kg; body mass index: 23.5, SD?=?2.3) volunteered to participate in this study. The kinematic data of the breakfall motion for both osoto-gari and ouchi-gari were collected using a three-dimensional motion analysis technique (200?Hz). We observed significant differences between the movement patterns for the two techniques, especially in the lower extremity movements. In addition, a significantly greater peak extension momentum (osoto-gari: 1.29, SD?=?0.23?kg?m^2?s^?1; ouchi-gari: 0.84, SD?=?0.29?kg?m^2?s^?1) and lower head position along the vertical axis (osoto-gari: 0.18, SD?=?0.05?m; ouchi-gari: 0.31, SD?=?0.08?m) with a large effect size were found in the breakfall for osoto-gari. Our results suggest that a different paradigm is needed for effectively teaching each breakfall technique that will enable us to substantially lower the risk of judo-related head injuries in novice judokas.  相似文献   

健美操运动员前交叉韧带损伤的康复方案研究——Ⅰ度损伤的保守治疗     

牛金榜 《体育科技文献通报》2020,(2):150-151,154

膝关节是人体负重和运动的主要关节,前交叉韧带(ACL)损伤是膝关节最常见运动损伤之一,而健美操运动也是造成膝关节前交叉韧带损伤的项目之一,本文通过运用文献综述的方法,广泛收集有关膝关节ACL损伤的基本理论及防治知识,通过前交叉韧带的生理解剖结构,并结合健美操项目的运动特点来分析造成前交叉韧带一度损伤的原因及根据原因提出预防措施,针对前交叉韧带一度损伤的早、中、晚三期的病理演变特征提出康复方案,对以后前交叉韧带一度损伤保守治疗的快速康复提供理论基础,并对以后健美操训练中前交叉韧带损伤的预防和韧带重建术后康复训练有重要意义。  相似文献   

竞技游泳运动员运动性伤病情况调查分析          下载免费PDF全文

檀志宗  楼俊华  李男 《体育科研》2019,(6):93-97

采用问卷调查法对浙沪两省市194名游泳运动员进行运动性伤病调查，主要从运动性伤病的类型、部位、性质方面对比分析不同竞技水平游泳运动员的伤病表型特征。结果显示：优秀运动员运动性损伤较常见，多以慢性劳损为主，损伤部位依次为肩关节、腰背部和膝关节；一般运动员常发生急性损伤，损伤部位依次为膝关节、肩关节和腰背部。两组运动员鼻炎和中耳炎均常见。因此，依据运动性伤病的可能原因与机制，需要制定有针对性的预防措施，以减少运动性伤病的发生。  相似文献   

乒乓球运动员以预防损伤为主的功能训练          下载免费PDF全文

李男  叶晶龙 《体育科研》2019,(5):95-98

功能训练的理念来源于康复领域，现已逐步应用到运动训练中。由于乒乓球运动的项目特征，乒乓球运动员肩关节、腰椎关节、膝关节、踝关节、腕关节等部位容易出现运动损伤。通过对乒乓球运动员常出现的功能问题进行分析，寻找存在的常见问题，进而提出相应的功能训练建议。乒乓球运动员可根据情况，增加改善肩关节、胸椎关节、髋关节、踝关节的活动范围的训练，提高肩胛骨、核心和下肢稳定性的训练，以及改善肩袖、躯干肌力不平衡的训练，通过针对性的功能训练有效减少乒乓球运动员损伤的发生。  相似文献   

Factors associated with concussion-symptom knowledge and attitudes toward concussion care seeking in a national survey of parents of middle-school children in the US     

Zachary Y. Kerr  Aliza K. Nedimyer  Melissa C. Kay  Avinash Chandran  Paula Gildner  K. Hunter Byrd  Juliet K. Haarbauer-Krupa  Johna K. Register-Mihalik 《运动与健康科学(英文)》2021,10(2):113

BackgroundDeveloping appropriate concussion prevention and management paradigms in middle school (MS) settings requires understanding parents’ general levels of concussion-related knowledge and attitudes. This study examined factors associated with concussion-symptom knowledge and care-seeking attitudes among parents of MS children (aged 10–15 years).MethodsA panel of 1224 randomly selected U.S. residents, aged ≥ 18 years and identifying as parents of MS children, completed an online questionnaire capturing parental and child characteristics. The parents’ concussion-symptom knowledge was measured using 25 questions, with possible answers being “yes”, “maybe”, and “no”. Correct answers earned 2 points, “maybe” answers earned 1 point, and incorrect answers earned 0 point (range: 0–50; higher scores = better knowledge). Concussion care-seeking attitudes were also collected using five 7-point scale items (range: 5–35; higher scores = more positive attitudes). Multivariable ordinal logistic regression models identified predictors of higher scores. Models met proportional odds assumptions. Adjusted odds ratios (aORs) with 95% confidence intervals (95%CIs) (excluding 1.00) were deemed statistically significant.ResultsMedian scores were 39 (interquartile range: 32–44) for symptom knowledge and 32 (interquartile range: 28–35) for care-seeking attitude. In multivariable models, odds of better symptom knowledge were higher in women vs. men (aOR = 2.28; 95%CI: 1.71–3.05), white/non-Hispanics vs. other racial or ethnic groups (aOR = 1.88; 95%CI: 1.42–2.49), higher parental age (10-year-increase aOR = 1.47; 95%CI: 1.26–1.71), and greater competitiveness (10%-scale-increase aOR = 1.24; 95%CI: 1.13–1.36). Odds of more positive care-seeking attitudes were higher in white/non-Hispanics vs. other racial or ethnic groups (aOR = 1.45; 95%CI: 1.06–1.99) and in older parental age (10-year-increase aOR = 1.24; 95%CI: 1.05–1.47).ConclusionCharacteristics of middle school children''s parents (e.g., sex, race or ethnicity, age) are associated with their concussion-symptom knowledge and care-seeking attitudes. Parents’ variations in concussion knowledge and attitudes warrant tailored concussion education and prevention.  相似文献   

Increasing hip and knee flexion during a drop-jump task reduces tibiofemoral shear and compressive forces: implications for ACL injury prevention training     

Liang-Ching Tsai  Yi-An Ko  Kyle E. Hammond  John W. Xerogeanes  Gordon L. Warren  Christopher M. Powers 《Journal of sports sciences》2017,35(24):2405-2411

Although most ACL injury prevention programmes encourage greater hip and knee flexion during landing, it remains unknown how this technique influences tibiofemoral joint forces. We examined whether a landing strategy utilising greater hip and knee flexion decreases tibiofemoral anterior shear and compression. Twelve healthy women (25.9 ± 3.5 years) performed a drop-jump task before and after a training session (10–15 min) that emphasised greater hip and knee flexion. Peak tibiofemoral anterior shear and compressive forces were calculated using an electromyography (EMG)-driven knee model that incorporated joint kinematics, EMG and participant-specific muscle volumes and patella tendon orientation measured using magnetic resonance imaging (MRI). Participants demonstrated a decrease in peak anterior tibial shear forces (11.1 ± 3.3 vs. 9.6 ± 2.7 N · kg^?1; P = 0.008) and peak tibiofemoral compressive forces (68.4 ± 7.6 vs. 62.0 ± 5.5 N · kg^?1; P = 0.015) post-training. The decreased peak anterior tibial shear was accompanied by a decrease in the quadriceps anterior shear force, while the decreased peak compressive force was accompanied by decreased ground reaction force and hamstring forces. Our data provide justification for injury prevention programmes that encourage greater hip and knee flexion during landing to reduce tibiofemoral joint loading.  相似文献   

植物生长调节剂在作物生产中的安全使用   总被引：5，自引：0，他引：5  

王小兰 《甘肃广播电视大学学报》2005,15(3):1-4

植物生长调节剂已广泛应用于农作物生产中，能有效改善作物生长状况，提高产品产量和品质，但使用不当也会造成严重的药害。在实际生产中要注意安全使用植物生长调节剂，根据作物品种和使用目标，来选择植物生长调节剂的类型，严格控制浓度及施用方法、时间和次数，从而充分发挥植物生长调节剂的效果。  相似文献   

First-rib stress fracture in two adolescent swimmers: a case report     

Sara Low  Michael Kern 《Journal of sports sciences》2016,34(13):1266-1270

First-rib stress fractures have been described in adolescent athletes in various sports, with only one prior case report of first-rib stress fractures in an adolescent female swimmer. There is a need for research on the cause, management, and prevention of these injuries as they lead to significant morbidity and critical time away from sport for these aspiring athletes. We aimed to describe first-rib stress fractures as a potential cause for non-specific atraumatic chronic shoulder pain in adolescent swimmers and to discuss the different presentations, unique risk factors, treatment, and potential injury prevention strategies of such fractures. We discussed two such cases which were successfully treated with activity modification with restriction of all overhead activity, gradually progressive physical therapy and a return to swimming protocol. First-rib stress fractures can vary in presentation and should be in the differential diagnosis in adolescent swimmers with chronic shoulder pain. These injuries can be successfully managed with rest from overhead activities and physical therapy. Gradual return to competitive swimming can be achieved even with non-union of a first-rib stress fracture. Emphasis on balanced strength training in different muscle groups and proper swimming technique is essential to prevent these injuries.  相似文献   

Validation of the Microsoft Kinect® camera system for measurement of lower extremity jump landing and squatting kinematics     

Moataz Eltoukhy  Adam Kelly  Chang-Young Kim  Hyung-Pil Jun  Richard Campbell 《Sports biomechanics / International Society of Biomechanics in Sports》2016,15(1):89-102

Cost effective, quantifiable assessment of lower extremity movement represents potential improvement over standard tools for evaluation of injury risk. Ten healthy participants completed three trials of a drop jump, overhead squat, and single leg squat task. Peak hip and knee kinematics were assessed using an 8 camera BTS Smart 7000DX motion analysis system and the Microsoft Kinect® camera system. The agreement and consistency between both uncorrected and correct Kinect kinematic variables and the BTS camera system were assessed using interclass correlations coefficients. Peak sagittal plane kinematics measured using the Microsoft Kinect® camera system explained a significant amount of variance [Range_hip = 43.5–62.8%; Range_knee = 67.5–89.6%] in peak kinematics measured using the BTS camera system. Across tasks, peak knee flexion angle and peak hip flexion were found to be consistent and in agreement when the Microsoft Kinect® camera system was directly compared to the BTS camera system but these values were improved following application of a corrective factor. The Microsoft Kinect® may not be an appropriate surrogate for traditional motion analysis technology, but it may have potential applications as a real-time feedback tool in pathological or high injury risk populations.  相似文献   

Ankle and knee kinetics between strike patterns at common training speeds in competitive male runners     

Daniel Kuhman  Daniel Melcher 《European Journal of Sport Science》2016,16(4):433-440

The purpose of this study was to investigate the interaction of foot strike and common speeds on sagittal plane ankle and knee joint kinetics in competitive rear foot strike (RFS) runners when running with a RFS pattern and an imposed forefoot strike (FFS) pattern. Sixteen competitive habitual male RFS runners ran at two different speeds (i.e. 8 and 6?min?mile^?1) using their habitual RFS and an imposed FFS pattern. A repeated measures analysis of variance was used to assess a potential interaction between strike pattern and speed for selected ground reaction force (GRF) variables and, sagittal plane ankle and knee kinematic and kinetic variables. No foot strike and speed interaction was observed for any of the kinetic variables. Habitual RFS yielded a greater loading rate of the vertical GRF, peak ankle dorsiflexor moment, peak knee extensor moment, peak knee eccentric extensor power, peak dorsiflexion and sagittal plane knee range of motion compared to imposed FFS. Imposed FFS yielded greater maximum vertical GRF, peak ankle plantarflexor moment, peak ankle eccentric plantarflexor power and sagittal plane ankle ROM compared to habitual RFS. Consistent with previous literature, imposed FFS in habitual RFS reduces eccentric knee extensor and ankle dorsiflexor involvement but produce greater eccentric ankle plantarflexor action compared to RFS. These acute differences between strike patterns were independent of running speeds equivalent to typical easy and hard training runs in competitive male runners. Current findings along with previous literature suggest differences in lower extremity kinetics between habitual RFS and imposed FFS running are consistent among a variety of runner populations.  相似文献