目的 比较老年男性和年轻男性在行走时足底动力学特征的差异,探讨增龄对足底动力学的影响.方法 应用鞋垫式压力测试系统比较13名老年男性和14名年轻男性在串联行走时左脚的受压时长、受压支撑百分比、开始受压支撑百分比、结束受压支撑百分比、最大压强、最大压强支撑百分比、平均最大压强、时间压强积分、最大压力、最大压力支撑百分比、平均压力和时间压力积分的差异.结果 老年组除内侧足弓外所有分区的受压时长明显大于年轻组,同时外侧足跟、外侧足弓开始受压支撑百分比明显大于年轻组,而内侧足跟、第2、3跖骨受压结束百分比明显小于年轻组;老年人整个足底最大压力和平均压力以及第2、3跖骨平均最大压强和最大压力明显小于年轻组.老年人整个足底、第4、5跖骨和4个小脚趾的时间压强积分以及整个足底、足跟和4个小脚趾的时间压力积分明显大于年轻组.结论 前后脚串联行走时,足底筋膜机能减退可能是老年人姿势控制能力下降的主要原因之一,趾长屈肌和趾短屈肌的屈趾作用增强对老年人姿势稳定性提高有一定的代偿作用.

随着年龄的增长,许多身体机能发生不可逆转的衰退,其中运动能力的下降更为明显.在日常生活中,老年人不仅会出现因大肌群动作能力下降而导致的行走缓慢、平衡控制困难等现象,还往往伴有使用餐具、刷牙或穿衣等动作技能的不佳,这些动作的执行更多的依赖于手部精细动作能力.手部精细动作能力是指个体主要凭借手以及手指等部位的小肌肉或小肌肉群在感知觉、注意力等多方面心理活动的配合下完成特定任务的能力[1],包括操纵物体的稳定性、灵活性和协调性等.手部精细动作能力的下降不仅严重影响老年人的生存质量,而且可能作为脑功能减退的一项重要提示[2-3].

We examined the effects of long-term exercise on age-related decline in static balance control through centre-of-pressure (CoP) measurements of four groups of participants: older controls, younger controls, older Tai Chi exercisers and older joggers. The participants stood quietly in a tandem stance on a force platform for 30 s with eyes open (EO) and eyes closed (EC). The older controls showed remarkably larger CoP and EC/EO ratios than younger controls and older Tai Chi exercisers. The EC/EO ratios of velocity in the mediolateral direction of older joggers were significantly smaller than those of older controls. Results suggest that the static balance of older controls showed a significant decline caused by age-related changes. Long-term Tai Chi and jogging, particularly the former, contributed to static balance control in older people. Older adults relied more on visual information in static postural control than young people. Tai Chi would be an ideal exercise for improving static balance in older people.

目的 探究增龄化对于老年人侧向姿势调控中踝关节、髋关节和躯干调节策略的影响.方法 水平干扰触发平台用以诱发年轻人和老年人在水平突发干扰时的姿势反应.表面肌电测试系统记录受试者在姿势反射中腓骨长肌、胫骨长肌、臀中肌和竖脊肌的肌电图.计算每个受试者在不同阶段的肌肉活动贡献率,分析其在姿势调控中的主导调节策略,并且比较老年人和年轻人肌肉活动贡献率的差异.结果 主导调节策略的分析结果发现老年人姿势主导调控策略局限于踝关节,躯干选择出现明显地减少.两组受试者肌肉活动贡献率差异的比较发现老年人踝关节肌肉明显大于年轻人(P<0.05),臀中肌和竖脊肌参与不足.结论 随着年龄的增加,老年人侧向姿势控制的调节效率出现明显下降.

PURPOSE: The study compared the effect of low intensity resistance exercise with blood flow restriction (BFR) in the proximal thigh under different occlusion pressure on muscle morphology and function. METHODS: Twenty-seven healthy college students who had no training experience were randomly divided into three groups by different occlusion pressure: 0 mmHg (CON), 120 mmHg (LBFR) and 180 mmHg (HBFR). Before and after 12 weeks training with an inflatable cuff (20% 1RM, half squat, 4 sets, 75 repetitions in total, 3 days a week) in three groups, the muscle thickness (MT) of rectus femoris and medius femoris were assessed by ultrasound for all subjects. The maximal isokinetic torque (ITmax), relative maximal isokinetic torque(R-ITmax) and maximal power (Pmax) were measured at angular velocities of 60°/sec by ISOMED 2000 System in dominant low limb of all subjects. RESULTS: The MT of rectus femoris and medius femoris in LBFR increased after training compared with pre-training (2.12±0.22 vs. 1.99±0.16 cm and 2.01±0.09 vs. 1.82±0.15 cm, p<0.05), as well as in HBFR (2.15±0.16 vs. 1.95±0.19 cm and 2.02±0.19 vs. 1.86±0.14 cm, p<0.01). The ITmax after training were higher than pre-training not only in LBFR (213.00±26.04 vs. 204.56±29.16 Nm, p<0.01), but also in HBFR (217.00±20.13 vs. 190.33±15.71Nm, p<0.01). A significant increase in R-ITmax was noted in LBFR than pre-training (2.87±0.35 vs. 2.74±0.38 Nm/kg, p<0.01), and also in HBFR (2.94±0.26 vs. 2.57±0.20 Nm/kg, p<0.01 ). However, there was no significant increase in Pmax after training in LBFR (124.78±18.93 vs. 119.89±13.32W, p>0.05) or HBFR (122.56±16.44 vs. 120.26±17.43W, p>0.05). There was no significant change in MT, ITmax, R-ITmax and Pmax before and after training in CON (p>0.05). Besides, the MT, ITmax and R-ITmax in LBFR and HBFR had a significant change compared with CON respectively after training (p<0.05). There was no any significant difference in the MT, ITmax, R-ITmax, Pmax between LBFR and HBFR after training (p>0.05). CONCLUSION: BFR training protocols under 120mmHg or 180mmHg pressure are effective in improving muscular morphology and function. But the higher occlusion pressure may not have more benefit in improving muscular performance than the lower occlusion pressure.

Objective To compare the differences in long-term jogging and Tai Chi in terms of neuromuscular latency and time to peak of surface electromyography (EMG) in older males during lateral sudden perturbation. In addition, an effective means to enhance neuromuscular response and muscle contraction efficiency of older males during lateral postural challenges was investigated. Methods Postural reactions of young males, older sedentary male controls (without regular exercises), older male joggers (with long-term jogging practice), and older male Tai Chi participants (with long-term Tai Chi practice) were evoked by means of a sudden unpredictable lateral translation platform. Surface EMG signals of peroneus longus, anterior tibialis, gluteus medius, and erector spinae were collected by an EMG detection and analysis system. Results The latencies of peroneus longus, anteri or tibialis, and gluteus medius were delayed in the older sedentary male controls compared with those in young males. The neuromuscular reactions of anterior tibialis and erector spinae in older Tai Chi male participants were faster than those of older sedentary male controls. The contraction speeds of peroneus longus, anterior tibialis, and gluteus medius in young males were higher than those in three older groups during sudden lateral perturbations. Conclusions Long-term Tai Chi practice can enhance the responses of ankle and trunk muscles of older males during lateral postural challenges, but it has little effect on the muscle contraction efficiency of older males.

影响老年人跌倒的因素众多,其中神经肌肉控制和感觉运动功能下降会损害老年人的姿势控制功能[1-2],导致跌倒风险的增加.受解剖结构的影响,衰老对人体侧向姿势控制的影响更为明显[3].单脚站立、直行避让、弯道行走、斜坡支撑等活动增加了老年人侧向姿势控制的难度[4-6],上述活动中身体质心的不当移动将改变老年人侧向姿势控制的策略,进而可能诱发跌倒的发生[7].跌倒导致的髋部骨折极大地降低老年人愈后的生活质量和减少老年人预期的寿命[8].因此揭示老年人侧向姿势控制能力下降的机制,深入分析相关影响因素,探索有效的干预措施对于提高老年人侧向姿势控制能力,预防老年人跌倒具有非常重要的研究意义.

OBJECTIVES:to investigate the effects of regular Tai Chi (TC) or jogging exercise on neuromuscular reaction in older people.DESIGN:cross-sectional study.SETTING:university biomechanics laboratory.SUBJECTS:21 long-term elderly TC practitioners were compared with 18 regular elderly joggers and 22 sedentary counterparts.MEASUREMENTS:electromyography (EMG) was used to detect the neuromuscular reaction of the leg muscles to an unexpected ankle inversion perturbation. The latency of the muscles, which was defined as the time that the moment of perturbation began to the onset of the EMG response, was evaluated.RESULTS:a one-way ANOVA revealed that there were significant differences in the latency of the rectus femoris (R) and anterior tibialis (T) muscles between the three groups, but that there were no differences in the latency of the semitendinosus (S) and gastrocnemius (G) muscles. Further tests indicated that the R and T muscles in the TC and jogging groups were activated significantly faster than those in the control group. No significant difference was found for the muscle onset latencies between the TC and jogging groups.CONCLUSION:maintaining information processing speed during ageing is important, because of the role that it plays in many everyday events. The R and T muscles in the regular TC and jogging groups showed faster responses to unexpected ankle inversion perturbations, which is helpful for the timely correction of postural disturbances, than those in the sedentary control group.

目的:比较规律太极拳、慢跑锻炼对老人静态姿势控制能力的影响,探索提高老人静态姿势控制能力的有效锻炼方式.方法:采用横向研究比较对照组(n=14)、慢跑组(n=14)、太极拳组(n=14)在睁眼和闭眼前后脚站立下足底压力中心(CoP)的差异.结果:睁眼3组间的CoP比较结果差别不大;在闭眼条件下对照组和慢跑组的CoP数据明显大于太极拳组,而慢跑组和对照组之间所有分析数据未有显著性差异.结论:规律的太极拳锻炼可以有效地提高老人的静态姿势控制能力,规律的慢跑锻炼对老人静态姿势能力的影响不明显;老人在静态姿势控制中对视觉因素的倚重使其在睁眼条件下的姿势控制得到一定的补偿.

Twelve boys with an average age of 9.9 years were instructed to carry backpacks that weighed 0%, 10% and 15% of their body weights (BWs) to complete planned and unplanned gait termination experiments. The craniohorizontal, craniovertebral and sagittal shoulder posture angles at the sagittal plane as well as the anterior head alignment and coronal shoulder posture angles at the coronal plane were analysed. Results revealed significantly smaller craniohorizontal and sagittal shoulder posture angles during planned gait termination and a significantly smaller sagittal shoulder posture angle during unplanned gait termination under loaded conditions compared with those at 0% BW backpacks. Furthermore, the coronal shoulder posture angles at 10% and 15% BW during planned and unplanned gait terminations were significantly larger than those at 0% BW. Therefore, subjects were more likely to have a forward head posture, rounded shoulder posture and increased lateral tilting of the shoulders during gait termination as backpack loads were increased. However, gait termination, whether planned or unplanned, did not elicit a remarkable effect on posture. Practitioner Summary: This descriptive study was performed to quantify the effects of carrying different backpack loads on the postures of children during planned and unplanned gait terminations. An increase in backpack loads resulted in a more forward head posture, more rounded shoulder posture and increased lateral tilting of the shoulders during unplanned gait termination.

Objective To provide theoretical reference for the research on lateral postural control in older people by using the electromyography(EMG)technique to compare the neuromuscular reaction between the young and older people during lateral perturbation.Methods Postural reactions of 14 young people and 14 older people as subjects were evoked by sudden unpredictable medio-lateral translation platform.The surface EMG data were collected from peroneus longus,anterior tibialis,gluteus medius and erector spinae of the left side of the body.Results The latencies in anterior tibialis,gluteus medius and erector spinae were obviously delayed in older people,and the duration of time to peak in peroneus longus,anterior tibialis and gluteus medius of older people was much longer than that of young people.Conclusions The delayed response of ankle,hip and trunk muscle and the low efficacy of contraction rate in ankle and hip muscles to the unexpected perturbation might be the primary reason for the decrease of lateral postural control in older people.

<正>步行是人们日常生活中最基本的运动方式,快步走也是人们常用的健身方法。通常情况下,人们的前向运动居多,后向运动相对较少。因此,大多数研究也主要集中于前向运动对于人体功能的作用,而忽视了后向运动对人体的积极影

One important extrinsic factor that causes foot deformity and pain in women is footwear. Women's sports shoes are designed as smaller versions of men's shoes. Based on this, the current study aims to identify foot shape in 1,236 Chinese young adult men and 1,085 Chinese young adult women. Three-dimensional foot shape data were collected through video filming. Nineteen foot shape variables were measured, including girth (4 variables), length (4 variables), width (3 variables), height (7 variables), and angle (1 variable). A comparison of foot measures within the range of the common foot length (FL) categories indicates that women showed significantly smaller values of foot measures in width, height, and girth than men. Three foot types were classified, and distributions of different foot shapes within the same FL were found between women and men. Foot width, medial ball length, ball angle, and instep height showed significant differences among foot types in the same FL for both genders. There were differences in the foot shape between Chinese young women and men, which should be considered in the design of Chinese young adults' sports shoes.

<正>步行是一个周期性的重复过程,其基本要求是身体保持平衡并完成位置移动,可分为三个阶段:步态启动阶段、中间的双足交替移动阶段和步态终止阶段,这三个阶段是一个连贯不可分割的整体。步行过程中任何一个阶段的改变都有可能影响身体

<正>随着经济发展,人们的生活方式发生变化,尤其是膳食结构的改变,肥胖已成为全球范围内的重要健康问题[1]。2003年,世界卫生组织报告指出,全球超重和肥胖人口数量已超过10亿,其中肥胖人口数量超过3亿人,并仍以惊人的速度

<正>膝骨性关节炎(osteoarthritis of the knee,KOA),作为临床常见的慢性关节病之一,严重影响了中老年患者的日常生活活动能力,给社会医疗和经济带来沉重负担。有资料显示,与西方国家相比,症状型KOA在中国更加普遍,并上升为一

This study examines the effects of a 16-week Tai Chi (TC) training program on the muscle strength, endurance, and reaction time of the lower extremities of elderly people. A total of 40 elderly individuals (aged ⩾60 years) completed the study. They were divided into two groups: the TC group (11 men and 11 women) underwent a supervised TC exercise program for 16 weeks, while the control group (9 men and 9 women) received general education for a comparable time period. Pre- and post-intervention measurements were conducted. An isokinetic dynamometer was used to measure the maximum concentric strength and dynamic endurance of the knee flexors and the extensors, and the maximum concentric strength of the ankle plantarflexors and dorsiflexors. The neuromuscular response of the rectus femoris, semitendinosus, gastrocnemius, and anterior tibialis muscles was measured by the onset latency to sudden perturbations using an electromyography system. After 16 weeks, the TC group showed a 19.9% increase in muscle strength of the knee flexors (p<.000) that was significantly greater than that in the control group (p=.046). There was also a significant decrease in semitendinosus muscle latency (6.6%, p=.014) that was significantly shorter than that in the control group (p=.042). No significant training effects were found in other measures. These results suggest that improving biomechanical characteristics of lower extremity muscles may need longer TC intervention for elderly people.

This study examined the proprioception of the foot and ankle complex in regular ice hockey practitioners, runners, and ballet dancers. A total of 45 young people with different exercise habits formed four groups: the ice hockey, ballet dancing, running, and sedentary groups. Kinesthesia of the foot and ankle complex was measured in plantarflexion (PF), dorsiflexion (DF), inversion (IV), and eversion (EV) at 0.4 degrees /s using a custom-made device. The results showed the following: (1) significantly better perceived passive motion sense in PF/DF was found as compared with the measurements in IV/EV within each group (P < .01); (2) ice hockey and ballet groups perceived significantly better passive motion sense in IV/EV than the running (P < .05) and the sedentary (P < .01) groups; and (3) no significant difference in the all measurements was found between running and sedentary groups. The benefits of ice hockey and ballet dancing on proprioception may be associated with their movement characteristics.

BACKGROUND:The objective of this study was to examine if there was any difference in the proprioception of the ankle and knee joints between pre-pubertal obese boys and non-obese boys.MATERIAL/METHODS:A cross-sectional experimental design was used in the study between two groups. Within the group, repetitions were performed to verify the differences in several passive motion senses in the ankle or knee. A total of 53 boys aged 7 to 12 served as the study subjects. Among them, there were 27 obese boys with an average body mass index (BMI) of 25.14+/-3.51 kg/m2 and 26 non-obese boys with BMI of 16.28+/-1.45 kg/m2. The study used custom-made apparatus to test any proprioception that was indicated by a kinaesthesis of the ankle and knee.RESULTS:The obese boys showed significantly poorer proprioception in knee flexion movement (P=0.041). However, they showed none in the knee extension and ankle movements.CONCLUSIONS:The obese boys showed a deficit in proprioception in knee flexion. Such alterations in their proprioception would be associated with decreased postural control capacity in obese boys as reported in published works since proprioceptive function is one important component that contributes to postural control.