Center Of Pressure Area Research Articles

A comparison of ground reaction force components according to the foothold heights in 16-t truck during downward step.

The aim of this study is to compare and analyze the components of ground reaction force (GRF) relative to the foothold heights during downward step of 16-t truck. Adult males (n= 10) jumped downward from each 1st, 2nd, 3rd foothold step and driver’s seat orderly using hand rail. Sampling rate of force components of 3 axis (medial-lateral [ML] GRF, anterior-posterior [AP] GRF, peak vertical force [PVF]), variables (COPx, COPy, COP area) of center of pressure (COP), loading rate, and stability index (ML, AP, vertical, and dynamic postural stability index [DPSI]) processed from GRF system was cut off at 1,000 Hz. and variables was processed with repeated one-way analysis of variance. AP GRF, PVF and loading rate showed higher value in case of not used hand rail than that used hand rail in all 1st, 2nd, and 3rd of foothold step. DPSI showed more lowered stability in order of 2nd, 3rd step than 1st foothold step used with hand rail, of which showed lowest stability from driver’s seat. COPx, COPy, and COP area showed higher value in case of 2nd and 3rd than that of 1st of foothold step, and showed lowest stability from driver’s seat. It is more desirable for cargo truck driver to utilize an available hand rail in order of 3rd, 2nd, and 1st of foothold step than downward stepping directly, thus by which may results in decrease of falling injuries and minimization of impulsive force transferring to muscular-skeletal system.

Carrying heavy asymmetrical loads increases postural sway during quiet standing in older adults.

Holding asymmetrical loads in the hands is common during many daily and occupational activities which, depending on the load mass, may alter postural stability. The purpose of this study was to determine the effect of load magnitude held asymmetrically in the hand on postural sway in older people. Eighteen healthy older adults (age 65.9 ± 5.7years) were assessed in the following conditions; (1) standing without an external load (0%), (2) standing while holding a grocery bag containing 5%, (3) 10% and (4) 20% body mass in the dominant hand. The total displacement of the centre of pressure (COP) in the anteroposterior and mediolateral directions (cm), mean COP velocity (cms-1) and COP area (cm2) were used to indirectly assess postural sway. The COP area (R 2 = 0.96), anteroposterior (R 2 = 0.85) and mediolateral (R 2 = 0.84) COP displacement increased linearly with additional load. The 20% load condition elicited the greatest increase in postural sway (d = 2.1-3.6) compared to 0%, while the 5% load had no effects on sway (P ≥ 0.05). In contrast, the mean COP velocity decreased by similar amounts when holding a load at 5% (d = 1.6), 10% (d = 1.4) and 20% (d = 1.5) body mass, compared to 0% (all P < 0.001). The slower COP velocity, combined with greater COP displacements may suggest that postural reactions were restricted and/or delayed. From a fall-prevention perspective, it is advised that older people avoid holding asymmetrical external loads greater than 5% of body mass.

The essential role of optical flow in the peripheral visual field for stable quiet standing: Evidence from the use of a head-mounted display.

It has long been thought that vision is the most essential factor in maintaining stable quiet standing compared to other sources (i.e., vestibular and somatosensory inputs) of information. Specifically, several vision studies on postural control have shown evidence for the importance of the visual system, particularly peripheral vision rather than central vision, and optical flow. Nevertheless, to date, no study has manipulated both visual field and optical flow concurrently. In the present study, we experimentally manipulated both the visual field (the central and peripheral visual fields) and the occurrence of optical flow during quiet standing, examining the effects of the visual field and optical flow on postural sway measured in terms of the center of pressure (CoP). Stationary random dot stimuli were presented exclusively in either the central or peripheral visual field, while the occurrence of optical flow was manipulated using a desktop (DTD) or a head-mounted (HMD) display. The optical flow that occurred while using the DTD was a function of the postural sway during quiet standing, while for the HMD, no optical flow occurred even when the body/head swayed during quiet standing. Our results show that the extent of postural sway (e.g., CoP area) was smaller when visual stimuli were presented in the peripheral visual field than that in the central visual field; this was the case while using the DTD alone, with no effects of the peripheral vision on the extent of postural sway while using the HMD. It is therefore suggested that the optical flow occurring in the peripheral visual field is essential for stable quiet standing.

Age-Related Changes in Postural Sway Are Not Consistent Between Land and Aquatic Environments

Quantifying how the environment (land vs water) influences age-related changes in postural sway is important for the development of new therapies that improve balance. The authors are not aware of any previous studies that have compared postural sway in an aquatic environment between age groups or when water depth and/or perturbations are incorporated into the comparison. The purpose of this study was to compare the effect of water depth and jet intensity on postural sway in older and younger adults. Sixteen older (age = 62.8 ± 9.56 years) and 15 younger (age = 22.5 ± 1.85 years) adults participated. Participants stood quietly for 90 seconds on land and at various water depths and jet intensities while center of pressure (CoP) sway was recorded using a force platform. Statistical comparisons revealed that CoP range and area measurements were different between land and aquatic conditions (P = .04 - .001). For example, CoP sway area in chest deep water (8.51 ± 2.97 cm) was greater than on land (2.41 ± 1.37 cm; effect size = 2.05). Furthermore, CoP sway area at the 60% jet intensity (71.4 ± 31.2 cm) was substantially greater than at the 20% jet intensity (12.4 ± 6.23 cm; effect size = 1.89). Surprisingly, the proportion of change across water depths and jet intensities was not consistent between older and younger groups as indicated by significant age by environment interactions (P = .03 - .001). Follow-up tests indicated that older adults swayed less than younger adults in water at the level of the hip (effect sizes = 0.42-0.94) and when water jets were applied at a 60% jet intensity (effect sizes = 0.63-1.97). Water immersion to the chest with high jet intensities produces the greatest CoP sway in both groups. This is likely a result of buoyancy and perturbation intensity. Less sway in the older group may reflect a strategy that reduces degrees of freedom for this group when faced with these stability challenges.

The Effect of Teeth Clenching on Dynamic Balance at Jump-Landing: A Pilot Study.

The aim of this study was to analyze the effect of teeth clenching on dynamic balance at jump landing. Twenty-five healthy subjects performed jump-landing tasks with or without teeth clenching. The first 3 trials were performed with no instruction; subsequently, subjects were ordered to clench at the time of landing in the following 3 trials. We collected the data of masseter muscle activity by electromyogram, the maximum vertical ground reaction force (vGRFmax) and center of pressure (CoP) parameters by force plate during jump-landing. According to the clenching status of control jump-landing, all participants were categorized into a spontaneous clenching group and no clenching group, and the CoP data were compared. The masseter muscle activity was correlated with vGRFmax during anterior jump-landing, while it was not correlated with CoP. In comparisons between the spontaneous clenching and the no clenching group during anterior jump-landing, the spontaneous clenching group showed harder landing and the CoP area became larger than the no clenching group. There were no significant differences between pre- and postintervention in both spontaneous clenching and no clenching groups. The effect of teeth clenching on dynamic balance during jump-landing was limited.

Angle of gaze and optic flow direction modulate body sway

Optic flow is a crucial signal in maintaining postural stability. We sought to investigate whether the activity of postural muscles and body sway was modulated by eye position during the view of radial optic flow stimuli. We manipulated the spatial distribution of dot speed and the fixation point position to simulate specific heading directions combined with different gaze positions. The experiments were performed using stabilometry and surface electromyography (EMG) on 24 right-handed young, healthy volunteers. Center of pressure (COP) signals were analyzed considering antero-posterior and medio-lateral oscillation, COP speed, COP area, and the prevalent direction of oscillation of body sway. We found a significant main effect of body side in all COP parameters, with the right body side showing greater oscillations. The different combinations of optic flow and eye position evoked a non-uniform direction of oscillations in females. The EMG analysis showed a significant main effect for muscle and body side. The results showed that the eye position modulated body sway without changing the activity of principal leg postural muscles, suggesting that the extraretinal input regarding the eye position is a crucial signal that needs to be integrated with perceptual optic flow processing in order to control body sway.

Effects of Holding an External Load on the Standing Balance of Older and Younger Adults With and Without Chronic Low Back Pain

ObjectiveThe purpose of this study was to assess the effect of holding an external load on the standing balance of younger and older adults with and without chronic low back pain (CLBP). MethodsTwenty participants with and 20 without CLBP participated in the study. Each group contained 10 younger (50% men) and 10 older adults (50% men). Participants were instructed to look straight ahead while standing on a force platform during two 120-second trials with and without holding an external load (10% of body mass). The center of pressure area, mean velocity, and mean frequency in the anteroposterior and mediolateral directions were measured. ResultsOlder adults had worse standing balance than younger adults did (P < .001, d = 0.20). There were no significant balance differences between participants with and without CLBP within age groups during standing balance condition. However, holding the external load significantly increased postural instability for both age groups and CLBP status, with mean effect size across center of pressure variables of d = 0.82 for older participants without CLBP and d = 2.65 for younger participants without CLBP. These effects for people with CLBP were d = 1.65 for subgroup of older and d = 1.60 for subgroup of younger participants. ConclusionHolding an external load of 10% of body mass increased postural instability of both younger and older adults with and without CLBP.

People with chronic low back pain have poorer balance than controls in challenging tasks

Purpose: To compare the balance of individuals with and without chronic low back pain during five tasks.Method: The participants were 20 volunteers, 10 with and 10 without nonspecific chronic low back pain, mean age 34 years, 50% females. The participants completed the following balance tasks on a force platform in random order: (1) two-legged stance with eyes open, (2) two-legged stance with eyes closed, (3) semi-tandem with eyes open, (4) semi-tandem with eyes closed and (5) one-legged stance with eyes open. The participants completed three 60-s trials of tasks 1–4, and three 30-s trials of task 5 with 30-s rests between trials. The center of pressure area, velocity and frequency in the antero-posterior and medio-lateral directions were computed during each task, and compared between groups and tasks.Results: Participants with chronic low back pain presented significantly larger center of pressure area and higher velocity than the healthy controls (p < 0.001). There were significant differences among tasks for all center of pressure variables (p < 0.001). Semi-tandem (tasks 3 and 4) and one-leg stance (task 5) were more sensitive to identify balance impairments in the chronic low back pain group than two-legged stance tasks 1 and 2 (effect size >1.37 vs. effect size <0.64). There were no significant interactions between groups and tasks.Conclusions: Individuals with chronic low back pain presented poorer postural control using center of pressure measurements than the healthy controls, mainly during more challenging balance tasks such as semi-tandem and one-legged stance conditions.Implications for RehabilitationPeople with chronic low back had poorer balance than those without it.Balance tasks need to be sensitive to capture impairments.Balance assessments during semi-tandem and one-legged stance were the most sensitive tasks to determine postural control deficit in people with chronic low back.Balance assessment should be included during rehabilitation programs for individuals with chronic low back pain for better clinical decision making related to balance re-training as necessary.

Relationships of Functional Tests Following ACL Reconstruction: Exploratory Factor Analyses of the Lower Extremity Assessment Protocol.

After ACL reconstruction (ACLR), deficits are often assessed using a variety of functional tests, which can be time consuming. It is unknown whether these tests provide redundant or unique information. To explore relationships between components of a battery of functional tests, the Lower Extremity Assessment Protocol (LEAP) was created to aid in developing the most informative, concise battery of tests for evaluating ACLR patients. Descriptive, cross-sectional. Laboratory. 76 ACLR patients (6.86±3.07months postoperative) and 54 healthy participants. Isokinetic knee flexion and extension at 90 and 180degrees/second, maximal voluntary isometric contraction for knee extension and flexion, single leg balance, 4 hopping tasks (single, triple, crossover, and 6-meter timed hop), and a bilateral drop vertical jump that was scored with the Landing Error Scoring System (LESS). Peak torque, average torque, average power, total work, fatigue indices, center of pressure area and velocity, hop distance and time, and LESS score. A series of factor analyses were conducted to assess grouping of functional tests on the LEAP for each limb in the ACLR and healthy groups and limb symmetry indices (LSI) for both groups. Correlations were run between measures that loaded on retained factors. Isokinetic and isometric strength tests for knee flexion and extension, hopping, balance, and fatigue index were identified as unique factors for all limbs. The LESS score loaded with various factors across the different limbs. The healthy group LSI analysis produced more factors than the ACLR LSI analysis. Individual measures within each factor had moderate to strong correlations. Isokinetic and isometric strength, hopping, balance, and fatigue index provided unique information. Within each category of measures, not all tests may need to be included for a comprehensive functional assessment of ACLR patients due to the high amount of shared variance between them.

Correlation between static postural balance, falls and pick torque isokinetic of extensors and flexors of the knee in elderly

Introduction: Declines of static postural balance and muscle strength, especially of lower limbs are strong predictors of falls in the elderly. Objective: The objective of this study was to identify the possible correlation between static postural balance, falls and isokinetic torque peak of knee extensors and flexors in the elderly. Methods: A cross-sectional study with anthropometric evaluation of static postural balance in unipodal limb support was performed using the force platform, flexural strength test and knee extension of the dominant limb using the isokinetic dynamometer and the application of a structured questionnaire on falls. They agreed to participate in the study 106 volunteers of both sexes through the signing of the free and informed consent. The data were treated in the Statistical Package for the Social Sciences program version 20.0. Results: There was a weak positive correlation between center of pressure (COP) area and peak flexion torque (r=0.204, p=0.041) and extension (r=0.228; p=0.022) of the knee, as well as peak extension (r=0.319, p=0.001) and lateral mean (r=0.324, p=0.001). A moderate positive correlation between COP area and anteroposterior velocity (r=0.694, p=0.000) and lateral mean (r = 0.646; p = 0.000) and strong positive correlation was found only between peak flexion torque and knee extension (r=0.719, p=0.000). Conclusion: There was a weak correlation between static postural balance and dominant lower limb muscle strength, and there was no correlation between falls and lower limb muscle strength, or between falls and static postural balance in the studied sample.

Examining Changes to Center of Pressure During the First Trials of Wii Gameplay.

Use of the Nintendo Wii™ as a balance assessment and rehabilitation tool continues to grow. One advantage of the Wii is that games can serve as a virtual reality training tool; however, a disadvantage of the Wii is the human-machine interface and the learning effect over multiple trials. The purpose of this study was to assess changes in postural control during Wii gameplay over a series of trials in novice players. Thirty-one university athletes (aged 18-25 years) completed four trials of the Nintendo Wii Fit™ soccer heading (SH) balance game. Center of pressure (COP) was calculated in the anterior-posterior (AP) and medial-lateral (ML) directions for each 70-second time trial at 1000 Hz. COP was assessed using six linear and two nonlinear measures. Repeated measures analysis of variances compared COP measures over the four trials. Significant differences in COP magnitude and velocity were found between trials 1 and 2 in the ML direction. No significant effects of trial were found in the AP direction. In contrast, a measure of the overall area of COP using an ellipse method revealed a significant reduction to COP area between trials 3 and 4. No significant differences between trials were observed in nonlinear measures. These results demonstrate how magnitude and velocity measures of COP control stabilize after the first trial of Wii SH game play in novice young adults. As Wii rehabilitation focuses on individuals with balance difficulties, an important consideration when using the game as an assessment tool is that more than four trials may be required to capture learning in these populations. In addition, contrasting results from ellipse measurement methods point to the use of multiple measures for robust description of COP behavior. This work provides understanding of normative postural control responses with further research in clinical populations needed.

Impacto da doença de Parkinson na performance do equilíbrio em diferentes demandas atencionais

RESUMO O objetivo deste estudo foi avaliar o equilíbrio de pacientes com doença de Parkinson (DP) na posição de tandem com os olhos abertos (OA), olhos fechados (OF) e em condição de dupla tarefa (DT). Trata-se de um estudo transversal composto por 19 indivíduos com DP nos estágios leve a moderado. Os pacientes foram avaliados em uma plataforma de força Biomec400. Os parâmetros analisados foram a área do centro de pressão dos pés (COP) e a amplitude e velocidade do COP nas direções anteroposterior (AP) e mediolateral (ML). Foram encontrados resultados estatisticamente significantes para amplitude AP e ML do COP e da área do COP, com valores maiores para as posições em tandem de OF e tandem com DT, quando comparados com a posição em tandem de OA. Os valores de velocidade média AP e ML foram maiores na posição em tandem de OF em comparação ao tandem de OA (p=0,009 e p=0), respectivamente. Concluiu-se que indivíduos com DP, quando submetidos a desafios cognitivos, comportam-se de forma semelhante à retirada do recurso visual no que diz respeito às alterações de equilíbrio. Isso reforça a necessidade de introduzir no plano terapêutico desses indivíduos atividades que requeiram o treino dessas habilidades.

Comparing postural balance among older adults and Parkinson's disease patients

The objective of this study was to compare postural balance among healthy older adults and Parkinson's disease (PD) patients during one-legged stance balance. We recruited 36 individuals of both sexes and divided them into two groups: healthy older adults (HG), and individuals with PD (PG). All the participants were assessed through a single-leg balance test, with eyes open, during 30 seconds (30 seconds of rest across trials) on a force platform. Balance parameters were computed from mean across trials to quantify postural control: center of pressure (COP) area and mean velocity in both directions of movement, anterior-posterior and medial-lateral. Significant differences between-group were reported for area of COP (P=0.002) and mean velocity in anterior-posterior direction (P=0.037), where poor postural control was related to PD patients rather than to healthy individuals. One-legged stance balance was a sensitive task used to discriminate poor postural control in Parkinson individuals.

Postural Control Strategies are Dependent on Reach Direction in the Star Excursion Balance Test

The Star Excursion Balance Test (SEBT) is a valid and reliable measure of dynamic postural control. Center of pressure (COP) behavior during the SEBT could provide additional information about direction-dependent SEBT balance strategies. The purpose of this study was to quantify spatiotemporal COP differences using COP area and velocity among three different SEBT reach directions (anterior, posteromedial, posterolateral). The anterior direction COP velocity was significantly lower than both posterior directions. However, the anterior COP area was significantly greater than posterior. Based on COP behavior, the anterior and posterior reach directions appear to use different postural control strategies on the SEBT.

Influence of Age on Postconcussive Postural Control Measures and Future Implications for Assessment.

To examine the influence of age, sex, attention-deficit hyperactivity disorder (ADHD) status, previous history of concussion, and days since injury on postconcussion postural control assessment in adolescents who have suffered a concussion. Prospective cohort study. Hospital-based outpatient clinic. Seventy-one participants (42 males; 29 females) with mean age 14.14 ± 2.44. Age, sex, previous concussion history, ADHD status, total and severity of postconcussion symptoms, and days since injury. Total Balance Error Scoring System score, path length, center-of-pressure (COP) area, sample entropy, and Romberg quotient. Pearson product-moment correlation coefficients were calculated to test for potential associations between the continuous participant characteristics and the postural control variables. Spearman correlation was used to test the association between symptom severity and the postural control variables. Standard multiple regression was used to model the extent to which participant characteristics accounted for the variance in the postural sway variables. Age was significantly associated with all of the postural sway variables except COP area for the eyes open condition and sample entropy in the anterior-posterior direction for the eyes closed condition. Sex, ADHD status, and previous concussion history did not significantly predict postural control scores. Age significantly influences scores on common postconcussion postural control assessments. This study demonstrates that age is a critical factor that needs to be accounted for to improve the clinical appropriateness and utility of current postconcussion postural control assessments.

Importance of Proprioceptive Information for Postural Control in Children with Strabismus before and after Strabismus Surgery.

The objective of this study is to examine the role of proprioception in postural balance in children with strabismus before and after realignment of their visual axes by eye surgery. Postural recordings were made with the TechnoConcept® force platform in 23 children. Several conditions were studied, whether the subjects had both eyes open, or either the dominant or the non-dominant eye open, without and with foam pads of 4 mm underfoot. Recordings were performed before and after strabismus surgery. The surface area, the length and the mean speed of the center of pressure (CoP) were analyzed. Before strabismus surgery, all children showed better stability with both eyes open with respect to the condition with the non-dominant eye open; furthermore postural stability improved in the presence of foam pads. After surgery, the surface area of CoP decreased significantly, especially in the non-dominant eye viewing condition. We suggest that strabismic children use mainly proprioceptive information in order to control their posture, but also visual inputs, which are important for obtaining a good postural stability. The alignment of the visual axes after surgery provides enhanced postural stability, suggesting, again the major role of visual inputs in the control of posture. Proprioceptive plasticity after strabismus surgery may allow better visual rehabilitation.

Comparison of scores obtained in videogame with biomechanical variables in stroke

Virtual reality (VR) promotes intensive training of a single task, enabling the motor learning, thereby affecting the recovery of postural control (PC) in individuals with stroke. Video game with balance platform are used as a form of intervention and, at the end of the game, a score is provided, but there is no evidence that it can be used as a quantitative parameter of PC. Objective: To determine whether there is a correlation between the score obtained by a video game and stabilometric variables. Methods: Nine individuals with stroke participated in an experimental protocol using the game Penguin Slide as intervention. The score was collected in the first and last sessions. The 2.0 AMTI force platform was used, with an acquisition frequency of 200Hz for evaluating before and after intervention. The volunteers were positioned with open eyes (OE) and closed eyes (CE) in the upright position for 1 minute, with one foot on each platform. Using the Matlab software, the variables of center of pressure (COP) were obtained: total COP area (ACOPt), COP area on the mediolateral (ACOPx) and anteroposterior (ACOPy) axis, average speed of COP (VCOP). The non-parametric paired Wilcoxon test (p &lt; 0.05) was used to compare the initial and final results of Penguin Slide game score and the pre and post intervention data obtained by the force platform in the OE and CE conditions. The analysis were done with the software R. Results: Comparison of initial and final score (p = 0.003). In OE condition, the initial and final comparison: ACOPt (p = 0.91), ACOPx (p = 0.57), ACOPy (p = 0.49), VCOP (p = 0.09). In CE condition, the initial and final comparison: ACOPt (p = 0.73) ACOPx (p = 1.0), ACOPy (p = 0.73) VCOP (p = 0.73). Conclusion: The VR did not provide PC improvement of the patients despite the score of the Penguin Slide game have increased significantly at the end of the protocol. Thus, there was no correlation between the score obtained by video game and the stabilometric variables

Does the type of visual feedback information change the control of standing balance?

The aim of this study was to evaluate whether different types of visual feedback influence the control of standing balance. Twenty-six subjects performed three tasks on a force platform: (1) standing with eyes open; (2) maintaining the own center of pressure (COP) displacement (internal feedback) on a target; and (3) pointing with a handheld laser pointer (external feedback) on a target. The COP and ankle displacements were measured through a force platform and a biaxial electrogoniometer, respectively, during 60s in each task. Global posturographic parameters were computed in the anterior-posterior and medial-lateral directions. In addition, the standard deviation and mean frequency of the ankle movements were also calculated in the sagittal plane. The sway area and standard deviation of COP differed between conditions, wherein smaller and higher values were typically observed during the internal and external feedback, respectively. Conversely, both the mean frequency and the mean velocity of COP were greater during internal feedback compared with other tasks, while external feedback usually leads to smaller values. Additionally, smaller and higher values for the ankle standard deviation and the ankle mean frequency, respectively, were observed during internal feedback, with the external feedback condition showing an opposite behavior. These results showed that the global postural sway and the postural adjustments at ankle during standing balance change depending on the type of visual feedback information.

Balance in subjects with congenital or early onset strabismus: Influence of age

Few studies have investigated the relationship between strabismus and balance, and those that do exist focused on patients within a limited age range, while no studies on possible age-related changes have yet been conducted. Therefore, the aim of our study was to investigate whether the balance strategies adopted by patients with congenital or early onset strabismus change with age. Forty strabismic patients and 36 healthy subjects were enrolled in the study. Both patients and healthy subjects were divided into three subgroups according to age (children, adolescents, and adults) and underwent a stabilometric evaluation. When we compared the whole group of strabismic patients with the group of healthy subjects, we found that the center of pressure area and the trunk oscillations in the former were significantly different from those in the latter; when we considered the three age groups separately, only values in children with strabismus were different from those in the age-matched control group of healthy subjects. Strabismus was found to affect balance in children by inducing a postural strategy characterized by a reduction in physiological trunk oscillations. Gaining a better insight into postural control in strabismic subjects and its evolution with age may be crucial to improving rehabilitation in such patients and planning tailored rehabilitation treatment.

Effects of Tai Chi training on postural control and cognitive performance while dual tasking - a randomized clinical trial.

This single-blinded, randomized controlled study investigated the effects of practicing Tai Chi on the postural control and cognitive performance of older women while dual tasking. Community-dwelling older women (n=31) were recruited from community centers. They were randomized to Tai Chi group (n=15, 12-form Yang style Tai Chi training) or a control group (n=16, general interest classes) for 16 weeks. Balance was tested in single leg stance after stepping down from a step, with and without a concurrent auditory response task (auditory Stroop test). Balance was measured by total sway path and sway area of subject's center of pressure (COP). The reaction time and the correctness of the auditory Stroop test were also measured. Tai Chi subjects made fewer errors in auditory Stroop test under dual-task condition after Tai Chi training (p=0.01). They also showed significant decreases in the COP path (p<0.05) and the COP area (p<0.05) in their postural control after training in both single- and dual-task conditions. The subjects in the control group did not show any significant improvement in dual-task condition after the intervention. Tai Chi training improves the cognitive and postural control performance of older women when dual tasking.