12-week melatonin supplementation improved dynamic postural stability and walking performance in persons living with multiple sclerosis: A randomized controlled trial.

BACKGROUND: Persons with multiple sclerosis (PwMS) suffer from sleep disturbances, fatigue and pain, which can be due, at least in part, to decreased levels of endogenous melatonin. These alterations could exacerbate postural instability, gait disorders and fall risk. Acute effects of exogenous melatonin on physical disorders have been studied in PwMS but its long-term effects on these parameters have not been explored yet in this population. This study aimed to determine the impact of chronic melatonin intake on dynamic postural stability, walking performance and fall risk in PwMS. METHODS: This randomized placebo-controlled study included 27 PwMS who were assigned to either melatonin group (MG, n=15) or placebo group (PG, n=12) (3 mg/night for 12 weeks). Dynamic postural balance (force platform), walking performance (locometer) and fall risk (Four Square Step Test) were evaluated pre (T0)- and post (T1)-intervention. Sleep quality (Pittsburgh Sleep Quality Index (PSQI)), fatigue perception (Fatigue Severity Scale (FSS)), neuropathic pain (Neuropathic Pain Questionnaire 4 (DN4)) and quality of life (International Multiple Sclerosis (MS) Quality of Life Questionnaire) were also assessed at T0 and T1. RESULTS: The center of pressure mean velocity decreased in MG compared with PG in the frontal plane (22.98 %, p=0.028). Stride length and walking speed increased in MG comparatively with PG (18.09 %, p=0.036; 9.65 %, p=0.025, respectively). The PSQI (55.89 %, p<0.001), FSS (32.38 %, p=0.003) and DN4 (32.41 %, p=0.035) scores decreased in MG compared with PG. CONCLUSION: 12-week melatonin supplementation can be recommended for managing MS-related gait disorders and dynamic postural imbalance. This therapy may also be prescribed for PwMS due to its anti-fatigue and analgesic effects as well as its benefits on sleep quality. CLINICAL REGISTRATION: This study was prospectively recorded in the Pan African Clinical Trial Registry database (PACTR202007465309582) (https://pactr.samrc.ac.za/.).

Mecánica y energética durante la marcha en cinta caminadora en adultos uruguayos saludables: efecto del IMC y la edad / Mechanics and energy during treadmill walking in healthy uruguayan adults: effect of BMI and age / Mecânica e energia durante a caminhada em esteira em adultos uruguaios saudáveis: efeito do IMC e Idade

La evaluación de la marcha en cinta caminadora puede resultar relevante para la toma de decisiones clínicas. No obstante, factores demográficos como la edad y el IMC pueden alterar la interpretación de los resultados. Nuestro objetivo fue obtener variables espacio- temporales, energéticas y costo de transporte durante la velocidad autoseleccionada en cinta caminadora para una muestra representativa de adultos uruguayos (n=28) y evaluar si diferentes rangos de edades e IMC pueden ser factores a tener en cuenta en pruebas clínicas donde se consideren dichas variables. Participaron 17 hombres y 11 mujeres (39,3 ± 14,8 años, 75,9 ± 12,5 kg, 1,74 ± 0,09 m, IMC 25,2 ± 4,06). Se realizó una reconstrucción 3D del movimiento en forma sincronizada con el consumo energético. Se obtuvieron valores de referencia y luego de agrupar los participantes según su IMC y rango de edad se compararon los datos mediante test de t (p≤0.05). Los resultados revelaron discrepancias significativas en las medidas espacio-temporales y energéticas de los adultos uruguayos al caminar en cinta con respecto a la literatura. La marcha difiere entre adultos jóvenes y de mediana edad en su velocidad autoseleccionada (p=0,03), longitud de zancada (p=0,01), trabajo mecánico externo (<0,001) y recuperación de energía mecánica (0,009), destacando la importancia de considerar la edad en evaluaciones clínicas. El IMC no influyó significativamente en estas variables. Estos hallazgos subrayan la necesidad de ajustar las interpretaciones de las pruebas clínicas de la marcha sobre cinta caminadora en adultos uruguayos de mediana edad (45 a 65 años).

Treadmill gait assessment can be relevant for clinical decision-making. However, demographic factors such as age and BMI may alter result interpretation. Our aim was to obtain spatiotemporal, energetic, and cost of transport variables during self-selected treadmill walking speed for a representative sample of Uruguayan adults (n=28) and to assess if different age ranges and BMI could be factors to consider in clinical tests involving these variables. Seventeen men and eleven women participated (39.3 ± 14.8 years, 75.9 ± 12.5 kg, 1.74 ± 0.09 m, BMI 25.2 ± 4.06). A synchronized 3D motion reconstruction was performed with energy consumption. Reference values were obtained and data were compared using t-tests (p≤0.05), after grouping participants by BMI and age range. Results revealed significant discrepancies in spatiotemporal and energetic measures of Uruguayan adults walking on the treadmill, compared to the literature. Gait differed between young and middle-aged adults in their self-selected speed (p=0.03), stride length (p=0.01), external mechanical work (p<0.001), and mechanical energy recovery (0.009), emphasizing the importance of considering age in clinical evaluations. BMI did not significantly influence these variables. These findings underscore the need to adjust interpretations of treadmill gait clinical tests in middle-aged Uruguayan adults (45 to 65 years).

A avaliação da marcha na esteira pode ser relevante para a tomada de decisões clínicas. No entanto, fatores demográficos como idade e IMC podem alterar a interpretação dos resultados. Nosso objetivo foi obter variáveis espaço-temporais, energéticas e custo de transporte durante a velocidade de caminhada autoselecionada na esteira para uma amostra representativa de adultos uruguaios (n = 28) e avaliar se diferentes faixas etárias e IMC podem ser fatores a serem considerados em testes clínicos que envolvam essas variáveis. Dezessete homens e onze mulheres participaram (39,3 ± 14,8 anos, 75,9 ± 12,5 kg, 1,74 ± 0,09 m, IMC 25,2 ± 4,06). Foi realizada uma reconstrução tridimensional do movimento sincronizada com o consumo de energia. Foram obtidos valores de referência e os dados foram comparados usando testes t (p≤0,05), após agrupar os participantes por IMC e faixa etária. Os resultados revelaram discrepâncias significativas nas medidas espaço-temporais e energéticas dos adultos uruguaios ao caminhar na esteira, em comparação com a literatura. A marcha diferiu entre adultos jovens e de meia-idade em sua velocidade autoselecionada (p=0,03), comprimento da passada (p=0,01), trabalho mecânico externo (<0,001) e recuperação de energia mecânica (0,009), destacando a importância de considerar a idade em avaliações clínicas. O IMC não influenciou significativamente essas variáveis. Esses achados destacam a necessidade de ajustar as interpretações dos testes clínicos de marcha na esteira em adultos uruguaios de meia- idade (45 a 65 anos).

A bidirectional pedestrian macroscopic speed model construction based on pedestrian microscopic simulation experiments.

Studies of macroscopic speed modeling of bidirectional pedestrian cross-flows have relied heavily on scenario experiments, but the data itself may be deficient because large-scale scenario experiments are not easy to organize and subjects may not be walking under normal conditions. In order to explore the possibility of using microscopic pedestrian flow simulations for macroscopic speed modeling of pedestrian flows, a series of two-way pedestrian cross-flow simulation experiments were designed. Bidirectional pedestrian flows are defined as Peds1 and Peds2. The crossing angle and pedestrian flow rate are used as variables, and a bidirectional pedestrian flows simulation is designed as an orthogonal experiment. The crossing angles range from 15 to 165 degrees, and bidirectional pedestrian flow rate range from 1 ped/s to 8 ped/s. A series of simulations are built and performed on the GIS agent-based modeling architecture (GAMA) platform. By analyzing the flow data of bidirectional flows in the crossing area, it is found that when the Peds1 density falls below a threshold, Peds1 speed is determined by pedestrians themselves and mainly remains in a free flow state; otherwise, the Peds1 speed decreases with density. The clear effects such as Peds2 density on the Peds1 speed cannot be determined. A piecewise function combined with a linear function and an exponential function is constructed as the Peds1 speed model considering the influence of the crossing angle. The calibration results show that the piecewise function should be better than the non-piecewise function. Compared to the results of established studies, the results in this paper have some differences. Therefore, the simulation method cannot completely replace the scene experiments. However, this approach can provide suggestions for subsequent refinement of the experimental program, as well as a feasible direction for the construction of a speed relationship for bidirectional pedestrian flows.

Effect of mediolateral leg perturbations on walking balance in people with chronic stroke: A randomized controlled trial.

Many people with chronic stroke (PwCS) exhibit deficits in step width modulation, an important strategy for walking balance. A single exposure to swing leg perturbations can temporarily strengthen this modulation. The objective of this parallel, double-blinded, randomized controlled trial was to investigate whether repeated perturbations cause sustained increases in step modulation (NCT02964039; funded by the VA). 54 PwCS at the Medical University of South Carolina were randomly assigned to one of three intervention groups: Control (n = 18), with minimal forces; Assistive (n = 18), pushing the swing leg toward a mechanically appropriate location; Perturbing (n = 18), pushing the swing leg away from a mechanically appropriate location. All intervention groups included 24 training sessions over 12-weeks with up to 30-minutes of treadmill walking while interfaced with a novel force-field and a 12-week follow-up period, with five interspersed assessment sessions. Our primary outcome measure was paretic step width modulation, the partial correlation between step width and pelvis displacement (ρSW). Secondarily, we quantified swing and stance leg contributions to step modulation, clinical assessments of walking balance and confidence, and real-world falls. Outcomes were analyzed for participants who completed all assessment sessions (n = 44). Only the Perturbing group exhibited significant increases in paretic ρSW, which were present after 4-weeks of training and sustained through follow-up (t = 2.42-3.17). These changes were due to improved control of paretic swing leg positioning. However, perturbation-induced changes in step modulation were not always significantly greater than those in the Control group, and clinical assessments were similar across intervention groups. Participants in the Perturbing group experienced a lower fall rate than those in the Control group (incidence rate ratio = 0.53), although our small sample size warrants caution. The present results indicate that perturbations can cause sustained modifications of targeted biomechanical characteristics of post-stroke gait, although such changes alone may be insufficient to change more complex clinical assessments.

Effectiveness and efficiency of aquatic therapy on independence in activities of daily living and mobility in post-acute spinal cord injury: A matched case-control study.

BACKGROUND AND PURPOSE: Aquatic therapy (AT), though potentially effective, lacks studies on clinical efficacy in patients with spinal cord injury (SCI). A recent study analyzing interviews with rehabilitation professionals on its clinical application reported that the scarce evidence of AT benefits was one of the actual barriers to its successful integration into clinical practice. We seek to provide evidence by comparing independence in activities of daily living (ADLs) and functional ambulation capacity in patients following rehabilitation which included AT and matched controls who followed rehabilitation without AT (non-AT). METHODS: Functional Independence Measure (FIM), Spinal Cord Independence Measure (SCIM-III), Walking Index for Spinal Cord Injury (WISCI-II) and its minimal clinically important difference (WISCI-II/MCID) were assessed. The AT group followed the Halliwick concept. We performed nonparametric nearest-neighbor k:1 matching for age, time since injury to admission, FIM at admission, level of injury (paraplegia/tetraplegia), completeness and cause of injury (traumatic, non-traumatic). The rehabilitation program comprised four daily hours of intensive treatment from the multidisciplinary team. Both groups received the same total number of rehabilitation hours at the same specialized clinical center and were admitted to follow inpatient rehabilitation within 2 months after injury. RESULTS: A total of 29 patients with SCI who followed AT (admitted between 2017 and 2023) were compared to historical matches selected from 551 inpatients with SCI (admitted between 2014 and 2023). For k = 1, the groups showed no significant differences in gains, efficiency, or effectiveness in FIM and SCIM-III; significant differences were observed in WISCI-II gain (p = 0.018) and WISCI-II efficiency (p = 0.046) in favor of the AT group; the proportion of patients achieving WISCI-II/MCID was significantly higher for the AT group (75.9% vs. 48.3%) (p = 0.030). These results were confirmed for k = 2. CONCLUSION: The AT group performed similarly in independence for performing ADLs and significantly better in ambulation than the matched historical controls.

Neural circuit mechanisms underlying context-specific halting in Drosophila.

Walking is a complex motor programme involving coordinated and distributed activity across the brain and the spinal cord. Halting appropriately at the correct time is a critical component of walking control. Despite progress in identifying neurons driving halting1-6, the underlying neural circuit mechanisms responsible for overruling the competing walking state remain unclear. Here, using connectome-informed models7-9 and functional studies, we explain two fundamental mechanisms by which Drosophila implement context-appropriate halting. The first mechanism ('walk-OFF') relies on GABAergic neurons that inhibit specific descending walking commands in the brain, whereas the second mechanism ('brake') relies on excitatory cholinergic neurons in the nerve cord that lead to an active arrest of stepping movements. We show that two neurons that deploy the walk-OFF mechanism inhibit distinct populations of walking-promotion neurons, leading to differential halting of forward walking or turning. The brake neurons, by constrast, override all walking commands by simultaneously inhibiting descending walking-promotion neurons and increasing the resistance at the leg joints. We characterized two behavioural contexts in which the distinct halting mechanisms were used by the animal in a mutually exclusive manner: the walk-OFF mechanism was engaged for halting during feeding and the brake mechanism was engaged for halting and stability during grooming.

A model of task-level human stepping regulation yields semistable walking.

A simple lateral dynamic walker, with swing leg dynamics and three adjustable input parameters, is used to study how motor regulation affects frontal-plane stepping. Motivated by experimental observations and phenomenological models, we imposed task-level multi-objective regulation targeting the walker's optimal lateral foot placement at each step. The regulator prioritizes achieving step width and lateral body position goals to varying degrees by choosing a mixture parameter. Our model thus integrates a lateral mechanical template, which captures the fundamental mechanics of frontal-plane walking, with a lateral motor regulation template, an empirically verified model of how humans manipulate lateral foot placements in a goal-directed manner. The model captures experimentally observed stepping fluctuation statistics and demonstrates how linear empirical models of stepping dynamics can emerge from first-principles nonlinear mechanics. We find that task-level regulation gives rise to a goal-equivalent manifold in the system's extended state space of mechanical states and inputs, a subset of which contains a continuum of period-1 gaits forming a semistable set: perturbations off of any of its gaits result in transients that return to the set, though typically to different gaits.

Effectiveness of a supervised group-based walking program on physical, psychological and social outcomes among older adults: a randomised controlled trial protocol.

INTRODUCTION: To minimise adverse health events among older adults, physical activity (PA) is considered one of the most fundamental and effective forms of lifestyle. Therefore, an urgent effort to promote a physically active lifestyle among our older adults is needed, in which walking could be a better choice, especially for mass promotion. Besides, the types of PA interventions were also shown to affect their effectiveness on older adults' psychosocial outcomes. Hence, the overall aim of the project is to examine the effectiveness of supervised group-based walking intervention by comparing it with unsupervised group-based walking and unsupervised individual-based walking interventions on improving physical, psychological and social outcomes among older adults in Hong Kong. METHODS AND ANALYSIS: The research will conduct a four-group (supervised group-based, unsupervised group-based walking, unsupervised individual-based, control group), double-blind, randomised control trial, targeting 184 older adults in Hong Kong. The primary outcomes will be measured by participants' changes in resting heart rates, body compositions, resting blood pressures, walking performance, loneliness, perceived social support and PA enjoyment. The results will be analysed using repeated analysis of variance and one-way analysis of covariance, as well as by conducting in-depth interviews with selected participants. Also, the outcomes of the research will be used as references for designing an effective walking operation manual for promoting healthy ageing among older adults in the community. ETHICS AND DISSEMINATION: The current study involves human participants, and the research protocol has been approved by the research ethics committee at Hong Kong Baptist University (Ref: R2022-2023-0013). All participants will be provided with written informed consent to participate. The outcomes of the intervention protocol will be disseminated through manuscript publications. TRIAL REGISTRATION NUMBER: The trial is registered at the ClinicalTrials.gov PRS (Trial ID: NCT05907252; date of first posted: 16 June 2023).

Cadence-Based Pedometer App With Financial Incentives to Enhance Moderate-to-Vigorous Physical Activity: Development and Single-Arm Feasibility Study.

BACKGROUND: High levels of physical activity are key to improving health outcomes, yet many people fail to take action. Using pedometers to target steps per day and providing financial incentives is a simple and scalable approach to promoting public health. However, conventional pedometers do not account for "intensity" and "duration," making it challenging to efficiently increase people's moderate-to-vigorous physical activity (MVPA), which is expected to improve health outcomes. Based on these rationales, we developed a smartphone app that sets step cadence as a goal (defined as a daily challenge of walking more than 1500 steps in 15 minutes twice a day, which is a heuristic threshold for moderate physical activity) and provides financial incentive when the challenge is met. OBJECTIVE: This study aimed to evaluate the feasibility of our novel app and explore whether its use can increase users' daily MVPA. METHODS: A single-arm pre-post study evaluated the feasibility and efficacy of the app. A total of 15 participants used app 1 (an app without financial incentives) for the first period (4 weeks) and then switched to app 2 (an app with financial incentives) for the second period (4 weeks). The primary outcome was the difference between the first and second periods in the number of successful challenge attempts per week. Secondary outcomes were differences between the first and second periods in daily steps and distance walked. Exploratory outcomes included the difference between the first and second periods in daily "heart points" as measured by Google Fit, a publicly available app that measures users' daily MVPA. RESULTS: The number of successful challenge attempts per week increased significantly compared to the first period (5.6 times per week vs 0.7 times per week; P<.001). Although not statistically significant, there was a trend toward an increase in the mean steps per day and distance walked per day (6586 steps per day vs 5950 steps per day; P=.19; and 4.69 km per day vs 3.85 km per day; P=.09, respectively). An exploratory end point examining daily MVPA by "heart points" collected from Google Fit also showed a significant increase compared to the first period (22.7 points per day vs 12.8 points per day; P=.02). CONCLUSIONS: Our app using step cadence as a goal and providing financial incentives seemed feasible and could be an effective app to increase users' daily MVPA. Based on the results of this study, we are motivated to conduct a confirmatory study with a broader and larger number of participants. TRIAL REGISTRATION: UMIN 000050518; https://center6.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000057420.

Brain-body-task co-adaptation can improve autonomous learning and speed of bipedal walking.

Inspired by animals that co-adapt their brain and body to interact with the environment, we present a tendon-driven and over-actuated (i.e.njoint,n+1 actuators) bipedal robot that (i) exploits its backdrivable mechanical properties to manage body-environment interactions without explicit control,and(ii) uses a simple 3-layer neural network to learn to walk after only 2 min of 'natural' motor babbling (i.e. an exploration strategy that is compatible with leg and task dynamics; akin to childsplay). This brain-body collaboration first learns to produce feet cyclical movements 'in air' and, without further tuning, can produce locomotion when the biped is lowered to be in slight contact with the ground. In contrast, training with 2 min of 'naïve' motor babbling (i.e. an exploration strategy that ignores leg task dynamics), does not produce consistent cyclical movements 'in air', and produces erratic movements and no locomotion when in slight contact with the ground. When further lowering the biped and making the desired leg trajectories reach 1 cm below ground (causing the desired-vs-obtained trajectories error to be unavoidable), cyclical movements based on either natural or naïve babbling presented almost equally persistent trends, and locomotion emerged with naïve babbling. Therefore, we show how continual learning of walking in unforeseen circumstances can be driven by continual physical adaptation rooted in the backdrivable properties of the plant and enhanced by exploration strategies that exploit plant dynamics. Our studies also demonstrate that the bio-inspired co-design and co-adaptations of limbs and control strategies can produce locomotion without explicit control of trajectory errors.

Impact of subtalar joint mobilization on walking ability in patients with intra-articular varus of the hindfoot joint with chronic ankle instability.

BACKGROUND: Patients with chronic ankle instability (CAI) often experience recurrent swelling and pain, which hinder their ability to walk long distances. Emerging evidence suggests that joint mobilization can enhance ankle function in patients with CAI. OBJECTIVE: The aim of this study is to investigate the effects of subtalar joint mobilization on enhancing ankle stability, alleviating ankle pain, and improving the walking ability of patients diagnosed with CAI. METHODS: A retrospective analysis was conducted on 46 patients who were treated between April 2022 and October 2023. They were randomly divided into two groups: a treatment group with 23 cases receiving conventional treatment along with subtalar joint mobilization treatment, and a control group with 23 cases receiving only conventional treatment. The treatment duration was eight weeks. Pain levels and walking ability were assessed before and after the treatment period. RESULTS: After eight weeks of treatment, the treatment group showed significant increases in the number of heel raises on the affected leg (NLHSL), improvements in the star excursion balance test (SEBT), and higher American Orthopedic Foot and Ankle Society (AOFAS) scores compared to the control group. Additionally, resting pain (RVAS) and walking pain (WVAS) scores were significantly lower in the treatment group. However, there was no statistically significant difference in single-leg standing time (SLT) between the two groups. Within the control group, post-treatment assessments indicated significant improvements in dynamic balance and control measures (SLT, NLHSL, SEBT), but no significant changes were observed in pain levels (RVAS, WVAS) or rear foot function (AOFAS). In contrast, the treatment group showed significant improvements across all measured parameters (RVAS, WVAS, SLT, NLHSL, SEBT, and AOFAS) following treatment. CONCLUSION: Subtalar joint mobilization effectively reduces ankle pain and enhances walking ability among patients with CAI by improving ankle stability. The observed improvements in walking ability may stem from mitigating compensatory mechanisms associated with varus of the calcaneus and ankle instability.

Gait Training of Healthy Older Adults in a Sitting Position using the Wearable Robot to Assist Arm-swing Rhythm, WALK-MATE ROBOT.

Although various walking training robots have been developed and their effectiveness has been recognised, operating these robots requires the implementation of safety measures to avoid the risk of falling. This study aimed to confirm whether arm swing rhythm training in the sitting position using an arm swing rhythm-assisted robot, WMR, improved subsequent walking. Healthy older adults (N = 20) performed arm swing rhythm training in a sitting position for 1 min × three times while being presented with tactile stimulation synchronised with the arm swing rhythm from a robot. An increase in walking performance was observed with increases in stride length and speed. In addition, the stabilisation of the gait pattern was observed, with a decrease in the proportion of the double-foot support phase and an increase in the proportion of the swing phase in one gait cycle. These results suggest that arm swing rhythm training in a sitting position using WMR improves gait in older adults. This will lead to the realisation of safe and low-cost robot-based walking training in sitting position.

Influencing factors analysis of asymmetry in knee adduction moment among patients with unilateral knee osteoarthritis.

BACKGROUND: The knee adduction moment(KAM) of both lower limbs in patients with unilateral knee osteoarthritis(KOA) exhibits asymmetry during walking, but the factors influencing this asymmetry remain unclear. This study aimed to explore the influencing factors of KAM asymmetry in patients with unilateral KOA. METHODS: A total of 148 patients with unilateral medial compartment KOA were selected for this retrospective study, and general data such as gender, age, and duration of disease were collected. The hip-knee-ankle (HKA) angle, degree of pain, and knee-extension muscle strength on the affected side were assessed through radiographic outcomes, the visual analog scale(VAS), and the Biodex isokinetic system. The peak KAM of both lower limbs was analyzed using a BTS motion-capture system and force platform. The asymmetry index(ASI) of KAM was calculated, and the patients were further categorized into the KAM symmetry group(ASI value ≤ 10%) and the KAM asymmetry group(ASI value>10%).Binary logistic regression analysis was employed to analyze the factors influencing the asymmetry of KAM. RESULTS: 90 patients were categorized into the KAM asymmetry group, representing 60.8% of the cohort. A significant difference in the ASI value of KAM was observed between the two groups. Correlation analysis identified nine factors, including sex, age, and BMI, that were positively correlated with the ASI value of KAM. In contrast, knee-extension muscle strength and per-capita monthly household income were negatively correlated with the ASI value of KAM. Regression analysis revealed that being female(OR = 1.752), older age(OR = 2.472), increased BMI(OR = 1.535), larger varus angle(OR = 3.965), higher VAS score(OR = 2.617), Kellgren-Lawrence(K-L) grade IV(OR = 4.474), history of knee joint trauma(OR = 5.684), and living in a rural location(OR = 1.554) increased the risk of KAM asymmetry. Conversely, increased knee-extension muscle strength(OR = 0.758) and a per-capita monthly household income of 3000 ~ 6000 yuan(OR = 0.814) decreased the risk of KAM asymmetry. CONCLUSION: Female gender, older age, increased BMI, larger varus angle, higher VAS score, K-L grade IV, history of knee joint trauma, and living in a rural location are identified as risk factors for KAM asymmetry. Conversely, increased knee-extension muscle strength and a per-capita monthly household income of 3000 ~ 6000 yuan serve as protective factors against this asymmetry.

Stacked-gait: A human gait recognition scheme based on stacked autoencoders.

Human gait recognition (HGR) is the mechanism of biometrics that authors extensively employ to recognize an individuals based on their walking traits. HGR has been prominent for the past few years due to its surveillance capability. In HGR, an individual's walking attributes are utilized for identification. HGR is considered a very effective technique for recognition but faces different problematic factors that degrade its performance. The major factors are variations in clothing, carrying, walking, etc. In this paper, a new hybrid method for the classification of HGR is designed called Stacked-Gait. The system is based on six major steps; initially, image resizing is performed to overcome computation problems. In the second step, these images are converted into grey-scale to extract better features. After that, the dataset division is performed into train and test set. In the next step, the training of the autoencoders and feature extraction of the dataset are performed using training data. In the next step, the stacking of two autoencoders is also performed. After that, the stacked encoders are employed to extract features from the test data. Finally, the feature vectors are given as input to various machine learning classifiers for final classification. The method assessment is performed using the CASIA-B dataset and achieved the accuracy of 99.90, 98.10, 97.20, 97.20, 96.70, and 100 percent on 000, 180, 360, 540, 720, and 900 angles. It is pragmatic that the system gives promising results compared to recent schemes.

Reference charts for the six-minute walk test in healthy school-aged children from the city of Zaragoza, Spain.

INTRODUCTION: The six-minute walk test is a stress test that provides information about exercise tolerance in chronic diseases. The aim of the study was to develop reference equations with normal values for the test in healthy children aged 6-12 years in our paediatric reference population. PATIENTS AND METHODS: The six-minute walk test was carried out in a sample of 236 healthy children, analyzing pre- and post-test variables, and we developed reference equations selecting variables that turned out to be significant (P < .05). RESULTS: The pre- and post-test values, respectively, were 97.82% (SD, 0.64) vs 97.82% (SD, 0.59) for oxygen saturation; 96.59 bpm (SD, 16.11) vs 131.89 bmp (SD, 22.64) for the heart rate; 0.52 (SD, 0.83) vs 3.01 (SD, 2.42) for the degree of dyspnea (Borg scale) and 0.68 (SD, 0.98) vs 2.95 (SD, 2.26) for the degree of lower extremities fatigue (Borg scale). The average distance walked was 668.03 m (SD, 87.36) (671.42 m in boys [SD, 92.2] vs 664.22 m in girls [SD, 81.81]). We fitted predictive equations that included the variables age, height and difference between baseline and final heart rate. We also generated percentile charts of the distance walked for height. CONCLUSIONS: Age, height, regular physical activity and obesity had an impact on test results. Obtaining reference values for the 6-min walk test in healthy children is necessary for its application in clinical practice.

The association of mental health with physical activity and its dimensions in Chinese adults: A cross-sectional study.

BACKGROUND: Selecting the most efficient type of physical activity that improves mental health can assist in choosing appropriate interventions. Hence, the objective of this study was to evaluate the associations between physical activity and its various aspects, including weekly physical activity, weekly walking and exercise sessions, and the frequency of walking and exercise per week, with the mental health of Chinese adults. METHODS: This cross-sectional study was carried out in Hangzhou (2023) involving 512 adults aged 18 and 64. Each participant received a self-completed questionnaire comprising three sections. The initial section focused on gathering basic information about the participants, such as gender, age, annual income, and marital status. The second section consisted of the 12-item General Health Questionnaire (GHQ-12), which aimed to evaluate the mental health status of the participants. Lastly, the third section included the International Physical Activity Questionnaire-Short Version (IPAQ-SV), which assessed the metabolic equivalent (MET) of activities like walking, moderate-intensity exercises, and high-intensity exercises. RESULTS: The study found that mental health problems affected 25.74% of adults, while physical inactivity was prevalent in 49.63% of adults. The statistical model was highly significant (F = 25.143, p < 0.001), suggesting that at least one predictor has a significant impact on mental health. The model accounted for 39% of the variance in mental health, with all variables showing predictive value. Notably, the number of walking days per week emerged as the most influential predictor of mental health (ß = -0.392), followed by level of weekly physical activity in MET, the number of exercise training sessions per week, weekly exercise training in MET, and weekly walking in MET (ß = -0.312, -0.301, -0.212, and -0.202, respectively). CONCLUSIONS: Adults can allocate more days per week to walking and their usual physical activity to improve their mental health.

Cognitive functions explain discrete parameters of normal walking and dual-task walking, but not postural sway in quiet stance among physically active older people.

BACKGROUND: Postural control is dependent on the central nervous system's accurate interpretation of sensory information to formulate and execute adequate motor actions. Research has shown that cognitive functions are associated with both postural control and fall risk, but specific associations are not established. The aim of this study was to explore how specific components of everyday postural control tasks are associated with both general and specific cognitive functions. METHODS: Forty-six community-dwelling older adults reported their age, sex, physical activity level, falls and fall-related concerns. The following cognitive aspects were assessed: global cognition, executive functions, processing speed and intraindividual variability. Postural control was quantified by measuring postural sway in quiet stance, walking at a self-selected pace, and walking while performing a concurrent arithmetical task. Separate orthogonal projections of latent structures models were generated for each postural control outcome using descriptive and cognitive variables as explanatory variables. RESULTS: Longer step length and faster gait speed were related to faster processing speed and less intraindividual variability in the choice reaction test. Moreover, longer step length was also related to less fall-related concerns and less severe fall-related injuries, while faster gait speed was also related to female sex and poorer global cognition. Lower dual-task cost for gait speed was explained by the executive function inhibition and faster processing speed. Postural sway in quiet stance was not explained by cognitive functions. CONCLUSIONS: Cognitive functions explained gait speed and step length during normal walking, as well as the decrease of gait speed while performing a concurrent cognitive task. The results suggest that different cognitive processes are important for different postural control aspects. Postural sway in quiet stance, step time and gait variability seem to depend more on physical and automatic processes rather than higher cognitive functions among physically active older people. The relationships between cognitive functions and postural control likely vary depending on the specific tasks and the characteristics of different populations.

Age related differences in whole body and body part angular momentum in the frontal plane during walking.

The contribution of body part angular momentum (BPAM) to whole body angular momentum (WBAM) in the frontal plane during walking differs across age groups. We investigated age related differences in BPAM and WBAM during walking. We used marker coordinate data from a publicly available database for 54 individuals aged 20-30 years and 78 aged 60-70 years. Angular momentum in the frontal plane was calculated as the sum of the translational component and the rotational component for each segment. The angular momentum of each segment was categorized into five BPAM: right and left lower limbs (foot, shank, and thigh), right and left arms (hand, forearm, and upper arm), and torso (head, thorax, and pelvis). BPAM at WBAM peak frames during stride cycles was compared between older and younger adults. The peak WBAM, angular momentum of the stance-and swing side upper limbs, and torso in older adults was significantly larger than that in younger adults, with increases of 74.6% in the stance-side upper limb, 127.5% in the swing-side upper limb, and 30.9% in the torso. These results suggest that interventions aimed at improving torso control could decrease the amplitude of WBAM in the frontal plane in older adults.

Infrared Thermography Sensor in the Analysis of Acute Metabolic Stress Response during Race Walking Competition.

Introduction: Due to the possible impact of the thermoregulatory process on sports performance, it is necessary to explore the existing relationships between kinetic, mechanical, and physiological variables. The objective of this study was to evaluate metabolic stress using thermography in the lower limb after the Spanish Championship 2023 walk. Method: A descriptive study was carried out on national and international race walkers before and after the 2023 Spanish Championships. The participants performed different tests within the same circuit. Five walkers completed the long-distance race of 35 km, four walkers completed the middle-distance race of 20 km and finally, two walkers completed the short-distance race of 10 km. Result: Statistically significant changes were observed in the lower limbs of the walkers after completing the test. We observed a decrease in skin temperature in all the anatomical regions analyzed, except for the back of the leg. More specifically, the decrease was in the hip (-1.92 °C: p = 0.004), quadriceps, hamstrings (-1.23 °C: p = 0.002), and tibia (-1.23 °C: p = 0.030). However, in the posterior region of the leg, a significant increase in temperature was observed (+0.50 °C: p = 0.011) following the competition. Discussion and Conclusions: The findings in this descriptive investigation support the notion that thermography may serve as a useful tool in the acute analysis of muscle functional activation and metabolic response in professional marching athletes. Moreover, the results confirmed that the change in skin temperature is the result of a variation in acute metabolic and functional activation in the lower extremities of race walkers during competition, with infrared thermography representing an instrument capable of detecting such a change in a rapid and non-invasive manner.