BACKGROUND:Modification of food consistency and volume is a commonly used method of swallowing compensation in clinical practice.Dry swallowing is a commonly used method of evaluation.The hyoid muscles are very important in swallowing.The effects of dry swallowing and swallowing tasks of different consistencies and volumes on hyoid muscle activation levels are still unclear. OBJECTIVE:To explore the effects of simple dry swallowing and swallowing tasks of different consistencies and volumes on the hyoid muscles in healthy adults. METHODS:A total of 44 healthy adults were included from April to August 2019,including 19 males and 25 females,with an average age of(21.7±2.8)years.They randomly performed dry swallowing and swallowing tasks of different consistencies(the International Dysphagia Diet Standardisation Initiative(IDDSI)frame levels 0-4)and volumes(5,10,20 mL),and the surface electromyogram signals of the hyoid muscles during each swallowing task were recorded.After processing the raw surface electromyogram signals,the activation levels of the hyoid muscles were compared between dry swallowing and swallowing tasks of different consistency and volume. RESULTS AND CONCLUSION:The mean amplitude values of the suprahyoid muscles corresponding to swallowing tasks of 20 mL for levels 0-4,10 mL for level 3,and 5 mL for level 4 were higher than those of dry swallowing(P＜0.05).The mean amplitude values of the suprahyoid muscles corresponding to the 20-mL swallowing tasks of different consistencies were higher than those of the 5-mL swallowing tasks of the corresponding consistencies,except for level 3(P＜0.05).The mean amplitude values of the suprahyoid muscles corresponding to the 20-mL swallowing tasks of different consistencies were higher than those of the 10-mL swallowing tasks of the corresponding consistencies,except for levels 2 and 3(P＜0.05).The mean amplitude values of the infrahyoid muscles corresponding to all swallowing tasks were higher than that of dry swallowing(P＜0.05).The mean amplitude values of the infrahyoid muscles corresponding to the 20-mL swallowing tasks of different consistencies were higher than that of the 5-and 10-mL swallowing tasks of the corresponding consistencies(P＜0.05).The mean amplitude values of the infrahyoid muscles corresponding to the 10-mL swallowing tasks of different consistencies were higher than those of the 5-mL swallowing tasks of the corresponding consistencies,except for level 3(P＜0.05).To conclude,in healthy adults performing swallowing tasks of different volumes and consistencies,the level of activation of the hyoid muscles is less susceptible to IDDSI frame levels 0-4 consistency and more susceptible to volume.The higher volume indicates the higher activation level of the hyoid muscles.

目的:系统评价可能导致髌股关节痛的生物力学危险因素.方法:检索资料库包括PubMed、Embase、Web of Science,以及中国知网、万方、维普,检索时限至2022年5月,筛选与髌股关节痛生物力学危险因素有关的前瞻性研究,提取运动学、动力学和肌电数据,采用Review Manager 5.3进行Meta分析.结果:最终纳入11项研究,总样本量6 587人,其中388人发生髌股关节痛.有限的证据表明较大的膝外翻是髌股关节痛的危险因素[I2=97％,SMD=1.32,95％CI(0.36,2.29)].亚组分析显示非常有限的证据表明较大的膝外翻是女性髌股关节痛的危险因素[I2=98％,SMD=2.49,95％CI(0.03,4.95)],而有限的证据表明较大的膝外翻不是男性髌股关节痛的危险因素[I2=81％,SMD=0.43,95％CI(-0.26,1.12)].髌股关节痛发病人群和未发病人群在其他运动学、动力学和肌电特征中未表现出显著性差异.结论:功能性活动中的膝外翻可能是女性产生髌股关节痛的生物力学危险因素,但是支持证据非常有限,且研究间具有较高的异质性.

Objective:To explore the effects of whole-body fatigue on the balance and ankle proprioception during drop landing of individuals with functional ankle instability(FAI)by comparing the differences in balance and pro-prioception between the FAI group and the control group before and after fatigue. Method:A total of 31 participants with unilateral FAI and 31 healthy participants were included in this study.A static balance test,dynamic balance test,and ankle proprioception test were conducted before and after fa-tigue.Sway distance(D)of the center of pressure(COP),root mean square of the COP(RMS),95％confi-dence ellipse area of the COP movements(95％AREA),normalized reach distance,and the area under the curve(AUC)were calculated and analyzed. Result:Before whole-body fatigue,the static balance,dynamic balance,and ankle proprioception during drop landing in FAI group were significantly lower than those in control group.After whole-body fatigue,the static balance,dynamic balance,and ankle proprioception during drop landing in the FAI group and control group decreased significantly(P＜0.05),and the increase of D,RMS and 95％AREA in FAI group were significant-ly larger than those in control group(P＜0.05),and the decrease of normalized reach distance in the postero-medial and posterolateral directions and AUC were significantly larger than those in control group(P＜0.05). Conclusion:Whole-body fatigue reduced the static balance,dynamic balance,and ankle proprioception,and the reduction was larger in FAI individuals than in healthy individuals.Therefore,whole-body fatigue may in-crease the risk of recurrent ankle sprain by reducing posture control and proprioception in FAI individuals.

跑步相关损伤是由跑步引起的下肢骨骼肌肉过劳性损伤,其在跑者群体中十分常见.明确跑步相关损伤的危险因素,对于制定损伤的预防和治疗策略至关重要.本研究归纳总结了跑步相关损伤的基本定义与流行病学概况,重点探讨分析了跑步相关损伤的内部和和外部危险因素及其主要干预手段.研究认为当前对于跑步相关损伤的定义尚未形成共识,不同研究间存在较大异质性,这也影响了对危险因素的确定,进而导致无法建立标准、有效的干预策略.今后研究应统一跑步相关损伤的定义,并开展更多高质量的前瞻性研究和随机对照试验来进一步确定跑步相关损伤的危险因素与干预手段.

目的:对比髌股关节痛业余跑者在有痛和无痛2种状态下跑步和落地起跳缓冲期的运动学和动力学数据,确定膝痛对膝关节生物力学特征的影响.方法:筛查选取15名男性和10名女性髌股关节痛业余跑者作为受试者并完成研究.每名受试者分别在有痛和无痛2种状态下完成生物力学测试,膝痛的诱发与消除通过改变跑量完成.采集所有受试者在跑步和落地起跳时的膝关节运动学和动力学数据.采用混合设计的双因素方差分析确定疼痛状态与性别对跑步和落地起跳缓冲期膝关节生物力学特征的影响.结果:男性和女性髌股关节痛业余跑者在有痛状态下跑步(P=0.001)和落地起跳(P=0.011)缓冲期的最大膝外展角度小于无痛状态.男性和女性髌股关节痛业余跑者在有痛状态下落地起跳缓冲期的膝伸力矩峰值(P=0.003)和髌股关节应力峰值(P=0.001)小于无痛状态.结论:膝痛会降低男性和女性髌股关节痛业余跑者在跑步和落地起跳缓冲期的最大膝外展角度,以及落地起跳缓冲期的膝伸力矩峰值和髌股关节应力峰值.膝痛代偿性地降低了髌股关节负荷,可能属于一种保护机制.

背景:护膝常被跑步爱好者用于预防和治疗髌股关节痛,但其所起到的干预作用机制仍不清楚.目的:确定护膝对不同性别髌股关节痛跑步爱好者跑步时主观痛感、下肢运动学和动力学特征的影响.方法:选取11名男性和9名女性髌股关节痛跑步爱好者作为受试者,通过目测类比量表、红外运动捕捉系统和测力台采集受试者在有、无穿戴髌骨稳定型护膝跑步时的主观痛感、运动学和动力学数据.研究通过北京体育大学运动科学实验伦理委员会批准,批准号:2020021H.参与试验的受试者均为自愿参加,对试验过程完全知情同意.结果 与结论:①男性和女性受试者在有护膝时跑步的目测类比量表得分小于无护膝时(P＜0.01);②女性受试者在有护膝时跑步缓冲期的最大膝屈角度小于无护膝时(P＜0.01),但男性在有、无护膝时跑步缓冲期的最大膝屈角度未出现差异(P＞0.05);男性和女性受试者在有护膝时跑步缓冲期的最大髋内收角度小于无护膝时(P＜0.01);男性和女性患者在有护膝时跑步缓冲期的膝外展(P＜0.01)和外旋力矩峰值(P＜0.01)大于无护膝时;③结果说明,护膝降低了男性和女性髌股关节痛跑步爱好者跑步时的主观痛感;减小了女性跑步时的最大膝屈角度和髋内收角度,以及男性跑步时的最大髋内收角度,护膝对下肢运动学特征的影响具有性别特异性;增大了男性和女性跑步时的膝外展和外旋力矩峰值,护膝可能引起膝关节负荷增大.

北京体育大学联合大连锐动科技有限公司和中国田径协会研发了一套基于机器学习的人体运动自动捕捉人工智能系统.目的:检验使用人体运动自动捕捉人工智能系统获得的人体关节点三维坐标的有效性.方法:在实际比赛中使用2台录像机拍摄12名女子标枪运动员的试投,取各自最好试投成绩的视频进行分析.使用直接线性转换(DLT)方法对录像机进行标定,标定误差=(0.003 4±0.001 2)m.4名有多年经验的研究人员独立手工解析动作视频中人体21个关节点的二维坐标,并合成三维坐标.同时使用人体运动自动捕捉人工智能系统自动识别了每次试投中21个关节点的二维坐标,并合成三维坐标(自动解析曲线).计算每名运动员每个关节点4名研究人员手工解析合成的三维坐标的平均值,作为关节点三维坐标最佳值(手工解析平均曲线).计算自动解析曲线和手工解析平均曲线之间的多重相关系数和差值的平均值、标准差和95％置信区间.结果:除了右脚尖Z坐标因为坐标变化量比较小外,自动解析曲线与手工解析平均曲线之间的多重相关系数均大于0.95,85％的自动解析曲线与相应的手工解析平均曲线的多重相关系数大于0.98.自动解析曲线与手工解析平均曲线之间的差值全部小于0.015m,50％的自动解析曲线与手工解析平均曲线之间的差值小于0.010 m.结论:基于机器学习的人体运动自动捕捉人工智能系统准确地模拟了手工解析过程,所获得的人体关节点三维坐标与有经验的研究人员手工解析获得的三维坐标平均值高度相似.该系统极大地节省了科技助力的人力并提高了数据反馈速度,已成功应用在多个田径项目和冬季运动项目的科技助力工作中.

目的:对比慢性踝关节不稳(CAI)者和健康者穿着高、低帮篮球鞋进行侧切动作时的下肢生物力学特征,为评估前交叉韧带损伤风险提供依据.方法:13名患有踝关节不稳的业余篮球运动员(单侧CAI组,年龄:21.1±2.4岁)和13名健康运动员(健康对照组,年龄:21.9±3.0岁)分别穿着高低帮篮球鞋进行45°和180°侧切动作.采用红外运动捕捉系统和三维测力台同步采集所有测试动作的运动学和地面反作用力数据.结果:穿着高帮球鞋进行两种侧切动作时最大垂直地面反作用力均大于低帮,踝关节内翻运动幅度均小于低帮,在180°侧切时踝关节背屈和膝关节屈曲幅度小于低帮.无论穿着高帮或低帮球鞋,45°侧切时地面反作用力指标均大于180°侧切,膝关节屈角和屈曲运动幅度、踝关节跖屈角和内翻运动幅度均小于180°侧切;踝关节不稳者与健康者在踝关节、膝关节运动幅度和地面反作用力等指标上均无差异.结论:(1)穿着高帮球鞋会减小踝关节内翻和膝关节屈曲运动幅度,并可增大地面反作用力,提示穿着高帮球鞋可能增加前交叉韧带损伤风险.(2)无论穿着高帮或低帮球鞋,45°侧切时较180°侧切均具有更小的膝关节屈角和更大的地面反作用力,提示45°侧切动作具有更大的前交叉韧带损伤风险.(3)无论穿着高帮或低帮球鞋,踝关节不稳者在侧切时下肢生物力学特征与健康者并无差异,提示踝关节不稳可能不会增加前交叉韧带损伤风险.

慢性踝关节不稳是篮球运动中常见伤病,可导致再次扭伤风险增大.高帮球鞋是预防扭伤的常用手段,但是否对踝关节不稳者具有防护作用仍不明确.确定鞋帮高度对有、无慢性踝关节不稳者侧切时踝关节生物力学特征的影响.选取13名慢性踝关节不稳者和13名对照者分别穿着高、低帮球鞋进行45°侧切变向动作,通过红外运动捕捉系统和测力台采集踝关节运动学和动力学数据.慢性踝关节不稳者和对照者穿着高帮球鞋侧切时最大踝内翻角、最大踝内翻角速度和踝内翻活动幅度均小于低帮.高帮球鞋在一定程度上可提高踝关节侧向稳定性和降低扭伤风险,且对慢性踝关节不稳者与正常者均具有相同的防护效果.

探究不同方法处理运动学和动力学数据对运动仿真计算结果的影响,进而减小数据误差以提高运动仿真计算结果的准确性.采集1名普通男性在校大学生的一次下蹲跳(CMJ)测试的运动学和地面反作用力(GRF)数据,分别使用直接计算方法(DK)和逆向运动学方法(IK)计算关节运动学数据;对原始GRF数据(RF)分别进行10 Hz(SF)和50 Hz(HF)的Butter-worth 4阶低通滤波处理.应用OpenSim 3.3软件结合不同方式处理的运动学和GRF数据进行CMJ运动仿真,计算CMJ过程中下肢肌肉-肌腱长度变化和下肢各关节力矩.采用复相关系数(CMC)和平均绝对变化值(MAY)来评价结果的相似性.结果显示:①DK和IK计算的CMJ过程的关节角度曲线相似度高,CMC值为0.93～1.00,但两种方法计算的髋关节内收外展角及旋转角结果间差异较大,MAV值分别为4.40°和4.81°;②DK计算的下肢环节长度最大变化量达48 mm,IK计算的下肢环节长度在CMJ过程中保持不变;③两种方法计算的肌肉-肌腱长度相似度与各关节角度结果相关;④RF、SF和HF计算所得的下肢关节力矩结果相似,但落地缓冲阶段结果差异较大.所得结论如下:①使用IK方法处理运动学数据更有利于减小运动学数据误差,提高运动仿真结果的准确性;②不同截断频率低通滤波GRF数据对关节力矩计算结果的准确性有影响.建议根据运动特征,选择不同的截断频率处理GRF数据.

目的:探讨3种不同方向(前跳、斜跳与侧跳)单腿跳跃落地动作对造成非接触性ACL损伤风险的差异,同时考察神经肌肉疲劳对动作可能造成的影响.方法:采用红外光点运动捕捉系统与三维测力台,同步采集12名健康男性受试者在疲劳前、后完成的三种不同方向单腿跳跃落地动作,并对下肢的运动学和动力学参数进行统计分析.结果:与ACL损伤相关的部分下肢生物力学指标在不同动作及疲劳前、后存在一定的差异,触地时刻支撑腿髋关节屈角前跳＞斜跳＞侧跳;地面反作用力首次峰值时刻膝伸展力矩侧跳大于前跳,且疲劳后3种方向均有所增大;膝外展力矩侧跳与斜跳大于前跳;疲劳后地面反作用力首次峰值均有所增大.结论:侧跳与斜跳较前跳可能有更大的ACL损伤风险,尤其是侧跳落地动作的损伤风险相对较大;神经肌肉疲劳可增大单腿跳跃落地时的ACL损伤风险.

目的:探讨3种常用于评估前交叉韧带(ACL)损伤风险的落地测试动作(DL、DVJ和FVJ)之间的差异.方法:通过采用8镜头红外光点运动捕捉系统和2块三维测力台,同步采集由11名健康男性受试者完成的3种不同落地测试动作,并对下肢的运动学和动力学参数进行统计分析.结果:3种不同落地动作之间存在较大的差异:(1)DL触地时刻的屈髋和屈膝角较小,最大屈髋、屈膝和踝跖屈角较小,重心缓冲距离较短,最大地面反作用力和下肢刚度较大;(2)DVJ的最大踝背屈角较大,最大地面反作用力和下肢刚度较小;(3)FVJ触地时刻的屈髋和屈膝角较大,最大屈髋和屈膝角较大,最大伸髋和伸膝力矩较大.结论:3种测试动作在多项运动学和动力学指标之间存在较大的差异,FVJ存在相对更大的ACL损伤风险,其次为DL;较为僵硬的落地方式可增大ACL损伤的风险,在落地时应采用更为柔软的落地策略;为更好地识别与评估ACL损伤的风险因素及理解其损伤的发病机制,建议在今后进行ACL损伤风险评估及伤病预防的相关研究中可优先采用标准化的FVJ测试动作.

To analyze and evaluate the injury risks for sports dance athletes and propose the response measures for the main risks,purpose to avoid and reduce the risk of injury and help to guarantee the normal training and competition.Conclusion：The athletes can use two types of response measures which are avoid or reduce risk,the most widely used method is reduce risk.

To analyze and evaluate the injury risks for sports dance athletes and propose the response measures for the main risks,purpose to avoid and reduce the risk of injury and help to guarantee the normal training and competition.Conclusion:The athletes can use two types of response measures which are avoid or reduce risk,the most widely used method is reduce risk.

This paper studies the problems of injury risk for elite track and field athletes through the method of literature review,expert interview,questionnaire,logical analysis and statistics.The author makes classification on injury risk based on six influence factors of body shape and function,physical fitness,training,psychology,environment and self-management,using the Pareto and taxis method to evaluate the injury risk,and propose the response measures for the main risks of injury.The main purpose is to avoid and reduce the risk of injury and help to guarantee the normal training and competition.

Fast pitch movement of 6 excellent women pitchers in China National Softball Team have been taken photograph by three-dimensional camera for kinematic analysis.The results indicate that excellent pitchers in the team have mastered the whole course of pitching with good continuity.The acceleration and deceleration of shoulder,elbow and wrist joints of throwing arm during pitching process indicate its order,and the rules of each joint's velocity changing are approximately similar.Among kinematical indexes in pitching movement,their time of extending-tread,distance of extending-tread,speed of body center gravity descend,ball velocity and height of at leaving hand moment,have been on an advanced level in the world.

通过三维定点摄像的方法,对我国优秀短道速滑运动员500米的起跑动作进行技术分析,结果表明:我国男女短道速滑运动员在起跑阶段前三步每一步所用时间均稍长于世界优秀短道速滑运动员的平均用时,建议加强运动员启动反应速度训练;我国男女运动员在起跑阶段躯干倾角和蹬冰腿膝关节角均偏大,建议运动员应保持较低的姿势,以减小阻力;我国优秀短道选手的蹬冰角度和最大展膝、展髋角速度均偏小,建议在今后的训练中应加强冰刀对蹬冰角度的控制及下肢肌肉力量和爆发力的训练。