Cognitive tasks play a pivotal role in posture control among young adults. This study examined how concurrent cognitive tasks alter balance stability and sensory integration during single-leg stance by analyzing center-of-pressure trajectories and wavelet spectra to elucidate the neurobehavioral mechanisms underlying dual-task balance degradation. A cohort of 24 young adults completed both single postural control tasks and dual cognitive–postural tasks on a force plate. COP data and wavelet decomposition energy were computed and analyzed. The results revealed significant differences between the dual-task and single-task groups for Lxy, Ly, Vxy, and Vy (p < 0.05). Energy content analysis showed that the dual-task group had significantly different energy ratios across four frequency bands along the x-axis (p < 0.05). Our findings showed that dual-task conditions impair postural control in young adults, increasing anteroposterior sway and altering mediolateral energy patterns. This suggests a shift toward proprioceptive reliance during cognitive division, revealing cognitive–postural interference. These results support using dual-task assessments for fall risk evaluation and inform interventions for populations requiring cognitive–motor integration.

BackgroundExisting literature provides inconclusive evidence regarding the impact of pain on movement patterns, especially in medial meniscus injuries. This study investigated how pain induced by medial meniscus injuries affects walking movement patterns, focusing on the biomechanical mechanisms. The goal was to develop targeted rehabilitation.MethodsThirty control participants (15 male, 15 female), 23 individuals with medial meniscus injury but no pain (11 male, 12 female), and 51 individuals with medial meniscus injury and pain (24 male, 27 female) were recruited. Gait data was collected using eight inertial measurement units and a video camera. Pain characteristics were assessed using the Visual Analog Scale (VAS) score, Tampa Scale for Kinesiophobia (TSK), Pain Catastrophizing Scale, and pain duration score. Statistical analyses were conducted using a one-way ANOVA to compare movement patterns among the three groups. Bivariate correlation analyses were performed within the pain group to examine the relationship between pain characteristics and movement patterns. The p was set at 0.05.Results(1) ANOVA among the groups revealed significant differences (p < 0.05) in several parameters: a shorter swing phase, reduced hip and knee angles, increased variability index, increased calf-foot mean absolute relative phase (MARP) during the support phase, and decreased calf-foot MARP during the swing phase were associated with pain. (2) Within the pain group, pain in knee extension (PKE) was negatively correlated with hip and ankle angles, stride length, and thigh-calf MARP during the support phase (p < 0.05). The VAS exhibited a negative correlation with knee angle and stride length, and a positive correlation with shock attenuation (p < 0.05). The TSK showed a positive correlation with hip and knee angles, and calf-foot MARP during the swing phase, while it was negatively correlated with stride length (p < 0.05).ConclusionMedial meniscus injury-induced pain has several adverse effects, including prolonged walking swing periods, reduced angulation, and increased variability while positively influencing coordination and shock attenuation. Pain intensity, kinesiophobia, and pain freedom contribute to these changes. Therapists should focus on pain management and movement pattern retraining to develop personalized rehabilitation. The angle of the swing phase should be emphasized during retraining.Clinical Trial Registrationhttps://www.chictr.org.cn/showproj.html?proj=65961, identifier ChiCTR2000041087

Objective: This study aimed to establish a dominant and non-dominant limb muscle strength evaluation model to evaluate the asymmetry of lower extremity muscle strength. Methods: The hip, knee, ankle flexors and extensors of 86 runners were evaluated separately in different contraction modes and at different movement speeds. A principal component analysis was used to establish a model for evaluating dominant and non-dominant lower extremity muscle strength and to comprehensively evaluate the asymmetry of lower extremity muscle strength. Results: Six main factors were present in both dominant and non-dominant indicators of lower extremity muscle strength, with dominant indicators of lower extremity muscle strength explaining 80.413% of the total variance and non-dominant indicators explaining 78.607% of the total variance. Conclusions: In a population of healthy male runners, there were differences in the symmetry of lower limbs in the comprehensive assessment model. The main contribution of the non-dominant side was the knee muscles, and the dominant side was the hip and knee muscles, so this difference should be considered in constructing future muscle strength evaluation models. It is critical to understanding the design and function of the human muscle system, and can reduce the number of meaningful tests we perform on diverse populations and help us reduce asymmetry.

Background: The visual attention tracking task plays a pivotal role in studying posture control and gait regulation. This study aims to explore the effects of visual attention tracking tasks on gait performance in young adults, providing a theoretical basis for gait optimization strategies through dual-task training. Method: Twenty healthy young males were recruited. Participants in the experimental group performed a multi-objective tracking task while walking (dual-task, DT), while the control group performed only walking (single-task, ST). The Vicon motion capture system and gait analysis system were used to collect full-body kinematic and ground reaction force data. The symmetry index of key spatiotemporal parameters and continuous relative phase (CRP) metrics were calculated to assess gait symmetry and inter-joint coordination. Result: The dual-task condition led to significant alterations in gait patterns, characterized by increased stride time and frequency, as evidenced by a longer gait line and greater foot inclination angle. Furthermore, inter-joint coordination was disrupted, demonstrated by elevated magnitude of absolute relative phase values at the hip–knee and knee–ankle joints, alongside more variable continuous relative phase trajectories. Conclusions: Visual attention tracking during walking significantly compromises gait symmetry and inter-joint coordination in young adults, suggesting that divided attention during athletic activities may elevate injury risk and should be considered in training program design.

OBJECTIVES:This study sought to investigate the effect of muscle mass, muscle strength, and physical function on postural balance in Sarcopenia. METHODS:A total of 1026 subjects aged 60-years and older were screened for sarcopenia and assessed using clinical tests including the Romberg's test, Single Leg Standing Test (SLS), Five Times Sit to Stand Test (FTSST), Timed Up & Go Test (TUGT), and Y-Balance Test (YBT). RESULTS:The authors identified distinct predictive patterns: 1) Hand grip strength(muscle strength) emerged as the dominant predictor of static balance performance, while 2) Dynamic balance outcomes were jointly influenced by gait speed (physical function), muscle strength, and age. Notably, dynamic balance demonstrated greater susceptibility to age-related skeletal muscle decline compared to static balance. CONCLUSION:These findings propose clinically actionable pathways: resistance training to target muscle strength deficits for static balance improvement, and combined strength-functional training protocols for dynamic balance rehabilitation in sarcopenia management.

Cognitive tasks play a pivotal role in the posture control of young adults. The study aims to explore the characteristics of static posture control under dual-task conditions by using wavelet analysis, a frequency-domain analysis method, so as to understand the dynamic changes of posture control of young adults under dual-task conditions more comprehensively. 24 young adults (mean age 22.6 ± 2.3 years) completed single and cognitive-postural tasks on a force plate. Single-leg stance with eyes open lasted 60 seconds; cognitive task involved subtracting 7 from random numbers. Time-frequency features of center of pressure (COP) signal and wavelet decomposition energy were computed. Paired t-tests analyzed data. Dual-task group, compared to single-task, showed significant differences in COP indicators: total trajectory length, normalized length, and average velocity ( p <0.05), notably in y-axis length and velocity ( p <0.001). Energy content analysis found dual-task group significantly differed in energy ratio of four frequency bands along x-axis ( p < 0.05), but no differences along y-axis. Postural control ability in young adults was significantly impaired under dual-task conditions, manifested through reduced balance stability and altered sensory dependence strategies - specifically, increased reliance on proprioception over visual input. It provides a crucial basis for public health intervention to prevent falls, suggesting that proprioceptive training should be strengthened for high-risk groups, such as the elderly and occupationally exposed groups, and dual-task training should be incorporated into public health promotion strategies to reduce the risks related to falls.

Background Falls are a particularly important public health problem among older people. Early identification of risk factors is crucial for reducing the risk of falls in older adults. Studies have confirmed the effectiveness of sensor-based fall risk prediction models for the older population. This article aims to sort out the current use of wearable sensors in building fall risk models for older adults in the community and explore the suitable use of sensors in model construction and the prospects and possible difficulties of model application. Methods This scoping review was conducted from 26 November 2023 to 9 March 2024. It was searched through Web of Science, PubMed, OVID, EBSCO and CNKI using the terms “wearable sensor” or “inertial sensor” or “inertial motion capture” or “wearable electronic devices” or “IMU” or “MEMS” or “accelerometer” or “gyroscope” or “magnetometer” or “smartphone” and “fall” and “predict” or “prediction” and “older adults” or “older men” or “older women” or “elderly” and “community” or “neighborhood” or “dwelling”. Results Thirty-one articles were included, and the selection of sensor type, location, and other characteristics and indicators, as well as model types, was summarized. Discussion and Conclusions Wearable sensors with a frequency of 100Hz located in a combination of spine/ pelvis/ hip-shank-feet position is recommended. In addition, walking tests and TUG and its variants are appropriate in the community. However, more empirical research is needed to obtain the best model construction combination and apply it effectively to the community.

Objective To examine the effectiveness of virtual reality (VR)-based rehabilitation training in improving cognition, motor function, and daily functioning in patients with mild cognitive impairment and dementia. Data sources A systematic review of published literature was conducted using PubMed, Web of Science, Elsevier, Embase, Cochrane, CNKI, Networked Digital Library of Theses and Dissertations. Methods The search period was from inception to 7 October 2023. Eligible studies were randomized controlled trials evaluating the efficacy of VR-based rehabilitation training in patients with mild cognitive impairment or dementia versus control subjects. Methodologic quality was assessed with the Cochrane risk of bias tool, and outcomes were calculated as the standard mean difference between participant groups with 95% confidence interval. Results A total of 21 randomized controlled trials with 1138 patients were included. The meta-analysis showed that VR-based rehabilitation training had significant effects on Montreal Cognitive Assessment (SMD: 0.50; 95%CI: 0.05 to 0.95; P = 0.030), Trail-making test A (SMD: −0.38; 95%CI: −0.61 to −0.14; P = 0.002), and Berg Balance Scale scores (SMD: 0.79; 95%CI: 0.13 to 1.45; P = 0.020). A subgroup analysis revealed that the type of VR, and duration and frequency of interventions had statistically significant effects on cognition and motor function. Conclusion VR-based rehabilitation training is a beneficial nonpharmacologic approach for managing mild cognitive impairment or dementia. Immersive VR-based training had greater effects on cognition and motor function than non-immersive VR-based training, but non-immersive VR-based training was more convenient for patients with limitations imposed by their disease. Also, an intervention lasting 5–8 weeks and for >30 min at a frequency of ≥3 times/week achieved the best results. It indicated that a longer intervention cycle may not achieve the best intervention effect and training duration and schedule should be carefully considered when managing patients.

Background: With the advent of global aging, the health of the older population has become a critical public health challenge. The purpose of this study was to investigate the effect of dual-tasking on gait performance in patients with sarcopenia. Methods: Thirty participants with sarcopenia (age: 70.73 ± 4.12 yr, MMSE score: 26.90 ± 3.00), including 14 males and 16 females, were selected according to the diagnostic criteria of the Asian Working Group on Sarcopenia. All participants were instructed to perform the gait test in three modes: single task (ST), cognitive–motor dual task (CMDT), and motor–motor dual task (MMDT). Statistical analyses were performed using one-way ANOVA to evaluate the effects of different task types on gait parameters of the participants. Results: (1) Compared with ST walking, gait frequency, step length, and step speed decreased, and the gait cycle and double-support phase increased in patients with sarcopenia during dual-task walking (p < 0.05); (2) Compared with ST walking, gait variability indices such as stride frequency, stride length, and support period significantly increased in patients with sarcopenia during dual-task walking (p < 0.05). Conclusions: The increased difficulty in postural control caused by dual-task interference may reduce the safety of motor strategies in patients with sarcopenia and increase the risk of falls. Future studies should focus on the effects of exercise interventions on multitasking patterns in people with sarcopenia to promote balance function in these populations.

BACKGROUND:The related functions of skeletal muscle and brain decrease significantly with age, and muscle-brain-related diseases are primarily associated with each other. Exercise can promote the secretion of myokines in skeletal muscle, showing a beneficial effect on the function of both, reflecting muscle-brain crosstalk. However, the key mechanism of action of exercise-regulated myokines in muscle-brain diseases remains unclear. SUMMARY:This review is intended to sort out and explore the key mechanism of the effect of exercise regulatory myokines on muscle-brain diseases through summarizing the relevant literature on the level of motor regulatory myokines in recent years and pay special attention to the impact of exercise type, intensity, and duration on myokine expression levels. KEY MESSAGES:The mechanism by which exercise regulates myokine levels in muscle-brain diseases is explained, and an effective exercise prescription for myokine expression that is more suitable for the elderly based on relevant literature is proposed. This work may hold certain value for subsequent exercise treatment of chronic diseases in the elderly and for further research on muscle-brain crosstalk.

Background: In recent years, sports games based on virtual reality (VR) have been widely used in the prevention and treatment of diseases related to the elderly. However, there seems to be no consensus on the improvement and comparison of physical function, balance and falls in elderly people with balance impairment.Objective: This study aims to explore the effects of VR intervention on physical function, balance and falls elderly people with balance impairment. Methods: Systematic literature searches of the PubMed, Web of Science, Elsevier, Cochrane, CNKI, and Wanfang databases were performed for VR games-related randomized controlled trials or comparison studies among elderly participants with impaired balance, published in English or Chinese until March 20, 2022. The Cochrane collaboration risk of bias tool was used to evaluate the methodological quality of the studies. A meta-analysis was performed to calculate the standardized mean deviation or mean difference of the sample and its 95% confidence interval (CI) in VR games.Results: The systematic review included 23 studies. The results showed that VR intervention had significant ef-fects on hand grip strength (MD:1.30, P = 0.040), knee extension strength (MD:-6.27, P<0.001), five times sit-to stand test scores (MD:1.13, P = 0.030), timed up-and-go test scores (MD:-1.01, P = 0.001), berg balance scale scores (MD:2.37, P<0.001), and falls efficacy scale scores (SMD:-0.28, P = 0.020). Subgroup analysis results showed that VR intervention was more effective on improving TUG and BBS scores than the conventional ex-ercise group (MD=-0.54, P = 0.004; MD=3.24, P<0.001) and the non-intervention group (MD=-0.98, P = 0.001; MD=3.30, P < 0.001). The balance training-based VR had a significant effect on improving TUG (MD=-1.03, P 0.004) and BBS (MD=2.93, P<0.001), and 20-45 min intervention, >= 3 times/wk, 5-8 wk cycles were significant in improving TUG (MD=-0.89, P<0.001; MD=-0.75, P = 0.0003; MD=-1.54, P<0.0001). VR intervention significantly improved TUG (MD=-2.27, P<0.0001) and BBS (MD=3.41, P<0.0001) in older adults in the hos-pital or nursing home compared with those residing in communities.Conclusion: VR interventions can help the elderly with impaired balance to overcome traditional sports obstacles and improve physical function, balance and minimize falls. Balance training-based VR intervention is more effective in balance recovery and fall prevention compared with game program. An intervention plan comprising 20-45 min, 5-8 wk cycles, and >= 3 times/wk frequency has significantly higher effects for high-risk elderly populations living in hospitals or nursing homes.

目的:采用跑台试验与二级台阶试验测得最大摄氧量(VO2max),比较2种方法在研究男性和女性不同年龄段心肺耐力的相关性、差异性和一致性.方法:对79名20-60岁的受试者分别用跑台试验测得VO2max和二级台阶试验推算其VO2max,将两者的VO2max进行比较分析.结果:①二级台阶试验推算VO2max与台阶试验VO2max的相关系数达到 了 0.673,Kendall's W 一致性系数为0.540,其中20-30男女性和40-50岁男性的VO2maxKendall's W＞0.6 一致性程度较强,30-40岁女性的VO2maxKendall's W＜0.02 一 致性程度较差.②在跑台试验VO2max和二级台阶的VO2max有较高相关关系,二者在女性的相关系数高达0.856(P＜0.01),男性的相关系数为0.822(P＜0.01)③男女受试者在跑台试验中的VO2max显著性P=0.008＜0.05,说明男女测试者在跑台试验的VO2max存在显著差异,在二级台阶试验方面,VO2max推算值P＞0.05,说明其VO2max的推算值不存在性别差异.结论:跑台试验和二级台阶试验的VO2max基本一致,二级台阶试验可替代跑台实验.但是30-39岁和50-59岁的男性和30-60岁的女性,测得一致性系数相对较小,不建议直接用二级台阶试验替跑台试验.20-29的男女和40-49的男性可以直接二级台阶测VO2max.

Tai Chi is a treasure of Chinese excellent culture and has its unique advantages for the development of sports functions. Coordination ability and balance ability are important components of physical fitness and play an important role in the healthy development of human body. However, studies on Tai Chi developing the relationship of human’s coordination ability and balance ability have not been reported. Therefore, this paper studies the Tai Chi movement— "cloud hands with feet-together stance", and explores the relationship between the hand-eye coordination ability and center of gravity during the completion of the movement of "cloud hands with feet-together stance" in different postures of Tai chi, so as to provide experimental evidence for the application of Tai chi in fitness exercise.

The application of multi-tasking (MT), especially dual-tasking (DT), in frail older adults is currently gaining attention. The aim was to review the application of the MT mode on cognition and lower limb function in frail older adults, including the MT test and MT training. By searching five electronic databases, Scopus, PubMed, PEDro, Web of Science and the Chinese electronic database, a total of 18 studies were finally included in this study, with 7 articles on MT testing and 11 articles on MT training. The results of the study showed that the current testing and training of MT is mainly based on the DT mode, with a wide variety of test types and protocols, as well as a variety of outcomes. The included studies suggested that DT can be used as a test to assess cognitive and lower limb function in the frail population and that an MT (DT) training program with an intervention period of ≥3 months or a duration of ≥60 min per session could improve cognitive and lower limb function in the frail population, thereby reducing the risk of falls. Further research is required to explore the effects of different types of MT and task prioritization in frail older adults.

This review is aimed to assess the effectiveness of virtual reality (VR) games on cognition, mobility, and emotion in elderly stroke patients. We selected relevant articles from eight databases from 2011 to 2022 and extracted articles on cognitive ability (general cognition, mini-mental state examination (MMSE), Montreal cognitive assessment (MoCA) et al.), mobility (modified Barthel index (MBI), Fugl-Meyer assessment (FMA), Berg balance scale (BBS), functional independence measure motor (FIM MOT)), and emotion (depression/anxiety). Twenty-nine studies including 1311 participants were included in the analysis. In the results, virtual reality games were more effective in improving overall cognitive function in stroke patients compared to conventional therapies. In addition, the intervention group in the MMSE (SMD = 0.6, 95

目的:本研究以压力中心(COP)在前后方向上的速率特征为划分依据,探索非预期性重物摆干扰在COP不同运动阶段对踝关节调节过程的影响.方法:17名受试者单足站立于测力台上,实验人员分别在无提示和倒计时提示两种情况下释放悬吊于其后方天花板上的重物,通过无线表面肌电采集受试者胫骨前肌(TA)和腓肠肌(GAS)肌电,三维测力台用以记录受试者COP变化.结果:干扰前阶段,预期性干扰时两块肌肉RMS均高于非预期性干扰时(P＜0.05);COP减速向前阶段,非预期性干扰时两块被测肌肉的RMS值都小于预期性干扰时,其中TA有显著性差异(P＜0.05);COP减速向后阶段,两块肌肉在非预期干扰情况下的RMS值都高于预期时,其中TA有显著性差异(P＜0.05).结论:非预期性干扰不会引起TA和GAS的预激活;非预期性干扰会使TA在调整阶段产生更大的代偿性姿势调节,尤其在COP向后减速阶段.

Introduction: Running is one of the most popular sports in the world, but it also increases the risk of injury. The purpose of this study was to establish a modeling approach for IMU-based subdivided action pattern evaluation and to investigate the classification performance of different deep models for predicting running fatigue.Methods: Nineteen healthy male runners were recruited for this study, and the raw time series data were recorded during the pre-fatigue, mid-fatigue, and post-fatigue states during running to construct a running fatigue dataset based on multiple IMUs. In addition to the IMU time series data, each participant’s training level was monitored as an indicator of their level of physical fatigue.Results: The dataset was examined using single-layer LSTM (S_LSTM), CNN, dual-layer LSTM (D_LSTM), single-layer LSTM plus attention model (LSTM + Attention), CNN, and LSTM hybrid model (LSTM + CNN) to classify running fatigue and fatigue levels.Discussion: Based on this dataset, this study proposes a deep learning model with constant length interception of the raw IMU data as input. The use of deep learning models can achieve good classification results for runner fatigue recognition. Both CNN and LSTM can effectively complete the classification of fatigue IMU data, the attention mechanism can effectively improve the processing efficiency of LSTM on the raw IMU data, and the hybrid model of CNN and LSTM is superior to the independent model, which can better extract the features of raw IMU data for fatigue classification. This study will provide some reference for many future action pattern studies based on deep learning.

Nutritional supplements have been extensively used as health interventions for the elderly. However, with the spread of COVID-19, no consensus exists on whether nutritional interventions could improve muscle mass and physical activity in community-dwelling older adults. To conduct a systematic review and meta-analysis to explore the effects of different nutritional interventions on muscle mass and physical performance in the elderly, we searched PubMed, Web of Science, Elsevier, and Cochrane databases from their founding dates to December 2023. The meta-analysis was performed using RevMan5.3 software. Only randomized controlled trials (RCTs) were considered, and the overall mean difference (MD) or standardized mean difference (SMD) with 95% confidence interval (CI) was calculated. There were 33 studies comprising 3579 elderly persons meeting the inclusion criteria. Comprehensive analysis suggested that the intervention effect of fat-free mass (FFM), appendix skeletal muscle mass (ASMM), handgrip strength (HGS), gait speed, and short physical performance battery (SPPB) score was higher in the nutritional supplement group than in the control group. The results of subgroup analysis demonstrated that protein supplementation (SMD = 0.82, p < 0.0001) had an optimal effect on ASMM (SMD = 0.89, p < 0.0001) and FFM (MD = 2.09, p < 0.0001) in the elderly. Vitamin D supplementation (SMD = 0.52, p < 0.0001) had a marginal effect on ASMM, and energy supplementation (SMD = 0.39, p = 0.0005) had the lowest effect. Moreover, nutritional interventions had the most significant impact on HGS (MD = 1.06, p < 0.0001) and TUG (MD = 0.14, p < 0.0001) in individuals aged 65-75 years old, with positive effects on FFM (MD = 1.62, p < 0.0001) and HGS (MD = 0.82, p < 0.0001) when compared to healthy elderly individuals, and had greater effect on ASMM (SMD = 0.69, p < 0.0001) than on the elderly with sarcopenia. Nutritional supplements can enhance muscle mass and physical performance in the elderly, while protein is recommended for muscle function. The golden period for implementing nutritional interventions to improve muscle function is before the age of 75 years. However, the impact of nutritional interventions varies with age and population. Given the limited evidence on nutritional interventions, more detailed and high-quality studies are highly warranted in the future.

侧切动作被认为是导致前交叉韧带损伤的风险动作之一,备受竞技体育和大众健身领域研究的重视,该文通过检索国内外相关文献,对人体在完成侧切动作过程中潜在影响前交叉韧带损伤的因素进行总结,试图从人体生物力学角度明确侧切动作中前交叉韧带的损伤机制.该文从侧切角度、着地方式、预期非预期、性别与神经肌肉控制5个方面分析侧切动作的相关生物力学特征,结合人体前交叉韧带的特性探讨侧切动作的潜在损伤机制,以期为预防前交叉韧带损伤提供科学建议.

随着科技的发展,人们对电子设备的依赖性越来越强,引发的疾病也越来越多,尤其在颈部和腰部.而针对长时间保持某一颈腰椎角度是怎样影响人们的颈腰部肌肉疲劳程度这个问题,引起了学者们的广泛探讨.因此,该文从颈腰部肌肉的解剖结构和颈腰椎出现的问题入手,运用文献综述法,对近年来的研究进行分析,以期为人们缓解颈腰椎相关疾病提供新的思路.结果表明,目前还未有具体有效的方法来调整颈腰椎角度减少疲劳,建议以后在颈腰椎角度的基础上加强对颈腰椎发病机制的研究,从而指导人们正确的坐站姿.