Posturography measures in specific ballet stance position discriminate ballet dancers with different occurrences of musculoskeletal injuries.

BACKGROUND: This study aimed to identify the postural sway variables that can distinguish between ballet dancers with high and low occurrences of musculoskeletal injuries. METHODS: Fourteen professional ballet dancers were assigned to a high-occurrence group (N = 5, reports >2 injuries in the previous 6-months) or a low-occurrence group (N = 9, reports ≤1 injury). Center-of-pressure (COP) data were acquired using a force platform during the following tasks: single-leg stance with eyes open, single-leg stance with eyes closed, and demi-pointe stance with eyes open. The COP standard deviation (SD) and range (RA) in both the medial-lateral (ML) and anterior-posterior (AP) directions were estimated. Between-group comparisons were made through Welch's t-tests for unequal sample size along the effect size measure (Cohen's d). Spearman's rho was used to estimate the association between the number of injuries and the COP variables. The statistical threshold was set at 1%. RESULTS: A between-group effect was found only for the demi-pointe stance, with large effects for SDML (P = 0.006, d = 1.7), RAAP (P = 0.006, d = 1.7), and RAML (P = 0.005, d = 1.7). An inverse relationship was found between the number of injuries and the demi-pointe's COP range in both directions (Spearman's rho from -0.681 to -0.726, P = 0.007). CONCLUSIONS: COP measures taken in ballet-specific positions can distinguish between dancers with a high and low occurrence of musculoskeletal injuries. Suggestions are made to include ballet-specific tasks in the functional assessments of professional dancers.

Comparison of sway meter and Kinovea software as a tool of measurement for the sway parameters during quiet standing: An observational study.

BACKGROUND: Several attempts have been made to quantify postural sway, from simple observational techniques to advanced computer technology. Measuring sway using commercial motion tracking devices and force plates are expensive and not feasible in evaluation on non-standardised surfaces. Video cameras can be used as an affordable alternative to perform human motion capturing, and this data can be analysed using motion tracking software like Kinovea; a free, reliable software that provides valid data, and an acceptable level of accuracy in angular and linear measurements. This study evaluated the reliability of Kinovea software to measure the sway amplitude in comparison with sway meter. METHODS: Thirty-six young women were recruited by convenience to this prospective observational study. Sway amplitude of the participants were measured using a sway meter on three different surfaces, with eyes opened and closed conditions, using modified Lords sway meter and videography. Videos were later analysed using Kinovea motion analysing software. The quantitative data of sway parameters were analysed for reliability using intraclass-correlation co-efficient and Bland Altman plot. RESULTS: There was an excellent correlation (>0.90) between the sway measurement values obtained from both methods irrespective of the surfaces. But the reliability was greater for the medio-lateral sway on the pebbled surfaces (0.981), and least for the anterior posterior sway on the same surface. CONCLUSION: This study concludes that, there is an excellent reliability for the video based sway analysis using Kinovea software. Hence this method can be used as an affordable alternative to measure the sway parameters.

Dry needling of the flexor digitorum brevis muscle reduces postural control in standing: A pre-post stabilometric study.

There are studies that show the better balance after dry needling in lumbar pain. However, the postural control effects after foot dry needling are unknown. Our objective was to check if dry needling reduces postural control. Eighteen subjects with flexor digitorum brevis (FDB) muscle Myofascial trigger point were evaluated pre- and post-deep dry needling. We measured stabilometric variables in a pre-post study. We have found significant differences in three stabilometric variables: surface with eyes closed (29.36-53.21 mm2 ) (p = 0.000), medium speed of the laterolateral displacement with eyes closed (1.42-1.64 mm/s) (p = 0.004), and medium speed of the anteroposterior displacement with eyes closed (1.30-1.53 mm/s) (p = 0.025). Dry needling therapy application in FDB muscle reduces standing postural control with eyes closed.

Postural instructions affect postural sway in young adults.

BACKGROUND: Instructions to exert effort to correct one's posture are ubiquitous, but previous work indicates that effort-based postural instructions can impair balance control in older adults with and without neurodegenerative disease. Although less-studied, young adults are at high risk of injurious falls. RESEARCH QUESTION: How do different postural instructions influence static balance in young adults? METHODS: Single-session, counterbalanced, within-subjects design. Twenty young adults briefly practiced three different ways of thinking about their posture, then attempted to employ each way of thinking while standing on springy foam for 30 s with eyes open. Relax instructions were used as a baseline between experimental conditions. Effort-based instructions emulated popular concepts of posture correction using muscular exertion. Light instructions aimed at encouraging length and width while reducing excess tension. Postural sway was assessed with an inertial sensor at the low back. RESULTS: Effort-based postural instructions increased path length and jerk of postural sway during quiet stance, relative to Light and Relaxed instructions. SIGNIFICANCE: These results are consistent with previous work in older adults indicating that thinking of upright posture as inherently effortful impairs balance. Therefore, the common practice of instructing young adults to use effortful posture may impair their balance performance.

Can occupational health professionals successfully apply the Goldilocks Work Paradigm in a simulated work redesign?

This study aimed to assess occupational health professionals' application of the Goldilocks Work Paradigm in redesigning jobs for healthier physical behaviours while maintaining productivity. During a group simulation exercise, participants (n = 16) created job descriptions for four different occupation cases (factory worker, office worker, teacher, train driver) and then redesigned the jobs using the Paradigm. Substantial changes in the time spent in sitting (9-30%), standing (8-42%), walking (6-14%), and high-intensity (0-24%) physical behaviours were achieved, which if implemented would likely result in enhanced health for workers. Overall, occupational health professionals were able to successfully redesign fictitious jobs aligned with the Goldilocks Work Paradigm. The simulation task used in this study may be useful to train professionals and assist workplaces to understand and implement the Goldilocks Work Paradigm into practice.Practitioner summary: This study assessed whether occupational health professionals could be trained in the Goldilocks Work Paradigm through a job redesign simulation task. Participants were able to redesign jobs to achieve a healthier 'just right' balance of physical behaviours. Simulations may help workplaces understand and implement a Goldilocks Work approach into practice.

The influence of a vibrotactile biofeedback system on postural dynamics during single-leg standing in healthy older adults.

The effectiveness of sensory substitution technology, such as haptic-based vibrotactile biofeedback (VBF), has been verified for balance training and rehabilitation. However, whether VBF training changes postural dynamics in older people remains unknown. This study investigated the influence of VBF training on postural dynamics during single-leg standing in older adults, using detrended fluctuation analysis (DFA). Twenty older adults participated in this study. Measurement of postural sway comprised three phases: first measurement session as a baseline test, postural training (day 1), and second measurement session (day 2). The BF group received BF training during the balance training session, while the control group practiced single-leg stance without BF. The center of pressure (CoP) trajectory was recorded in the first measurement session (pre) and second measurement session (post) at 50 Hz. DFA revealed the presence of two linear scaling regions in the CoP, indicating the presence of fast- and slow-scale fluctuations. For the BF group, slow-scale postural dynamics revealed more anti-persistent behavior after training in the anterior-posterior direction. However, the control group showed a change toward more random dynamics after training. These different influences suggest that the BF system might improve error correction strategies during single-leg standing for older adults, while single-leg standing training without the BF system might cause the loss of controllability in single-leg standing. Further, the results of the DFA are discussed in the context of balance training using VBF.

Comparison between side-lying and standing positions for hip abductor strength assessment.

BACKGROUND: The hip abductor muscles control the pelvis in the frontal plane and allow the maintenance of trunk position and dynamic balance during weight-bearing activities. OBJECTIVE: To compare the side-lying and standing positions for hip abductor strength assessment with regards to torque production and myolectric activity. METHOD: Concentric and eccentric hip abductor peak torque and total work, and myoelectric activity of the tensor fascia lata, gluteus medius, and inferior and superior portions of the gluteus maximus muscles were measured during maximal isokinetic tests for hip abductor strength in the side-lying and standing positions. The Wilcoxon test was used to compare variables between the positions. RESULTS: Peak torque values did not differ between side-lying and standing positions for both concentric and eccentric contraction modes (p > .05). During standing position, greater concentric total work was observed (p = .013). This position resulted in a lower activity of the tensor fascia lata muscle (p = .005) compared to side lying position. Myoelectric activity of gluteus medius, and inferior and superior portions of the gluteus maximus was similar between positions (p > .05). CONCLUSION: Both positions presented similar peak torque values and, during the standing position, a greater concentric total work and lesser activation of the tensor fascia lata was observed. Standing position can be used when emphasis on the superior portion of gluteus maximus over the tensor fascia lata is intended.

Transcutaneous spinal direct current stimulation (tsDCS) does not affect postural sway of young and healthy subjects during quiet upright standing.

Transcutaneous spinal direct current stimulation (tsDCS) is an effective non-invasive spinal cord electrical stimulation technique to induce neuromodulation of local and distal neural circuits of the central nervous system (CNS). Applied to the spinal cord lumbosacral region, tsDCS changes electrophysiological responses of the motor, proprioceptive and nociceptive pathways, alters the performance of some lower limb motor tasks and can even modulate the behavior of supramedullary neuronal networks. In this study an experimental protocol was conducted to verify if tsDCS (5 mA, 20 minutes) of two different polarizations, applied over the lumbosacral region (tenth thoracic vertebrae (T10)), can induce changes in postural sway oscillations of young healthy individuals during quiet standing. A novel initialization of the electrical stimulation was developed to improve subject blinding to the different stimulus conditions including the sham trials. Measures of postural sway, both global and structural, were computed before, during and following the DC stimulation period. The results indicated that, for the adopted conditions, tsDCS did not induce statistically significant changes in postural sway of young healthy individuals during quiet standing.

Assessment of Balance Instability by Wearable Sensor Systems During Postural Transitions.

Several studies have demonstrated beneficial effects of real-time biofeedback for improving postural control. However, the application for daily activities, which also include postural transitions, is still limited. One crucial aspect is the time point of providing feedback, and thus its reliability. This might depend on the sensor system used, but also on how the threshold is defined. This study investigates which wearable sensor system and what kind of threshold is more reliable in a situation of a postural transition.To this end, we compared three sensor systems regarding their accuracy in timing in a stable and unstable postural transition in 16 healthy young adults: a multiple Inertial Measurement Unit system (IMU), a pressure Insoles System (IS), and a combination of both systems (COMB). Further, we contrasted two threshold parameters for each system: a Quiet Standing-based threshold (QSth) and a Limits of Stability-based threshold (LoSth).Two-way repeated measures ANOVAs and Wilcoxon tests (α = 0.05) indicated highest accuracy in the COMB LoSth, though with small differences to the IS LoSth. The LoSth showed more accurate timing than the QSth, especially in medio-lateral direction for IS and COMB.Consequently, for providing a reliable timing for a potential biofeedback applied by a wearable device in everyday life situations applications should focus on pressure insoles and a functional stability threshold, such as the LoS-based threshold.

Acute effect of core stability and sensory-motor exercises on postural control during sitting and standing positions in young adults.

Core stability exercises and exercises that stimulate sensory-motor information are recommended for the prevention of injuries and the maintenance and rehabilitation of deficits related to postural control (PC). However, the comparison of results between core stability and sensory-motor exercises in the literature is limited to sitting and standing positions. OBJECTIVE: To determine the acute effect of core stability and sensory-motor exercises on PC during sitting and standing in young adults. METHODS: A total of 39 participants, with a mean age of 23 years, were randomly divided into three groups (1) Core stability exercises; (2) Sensory-motor exercises; (3) Control. Each group performed a sequence of five specific exercises of core stability and sensory-motor exercises (except controls). PC was evaluated before and after exercise in the seated and the one-legged stance conditions using a force platform. RESULTS: No significant difference was found for any variables of postural oscillation (P > 0.05) among the three groups studied. The magnitude of the effect of interventions in general was a small to moderate effect (d = 0.02/-0.48). CONCLUSION: The findings show that acute intervention with core stability and sensory-motor exercises did not produce any significant effects (reduction of postural oscillation) on PC during sitting and standing positions in young adults.

The effects of body position and actual execution on motor imagery of locomotor tasks in people with a lower-limb amputation.

Motor imagery (MI) is usually facilitated when performed in a congruent body position to the imagined movement, as well as after actual execution (AE). A lower-limb amputation (LLA) results in important structural and functional changes in the sensorimotor system, which can alter MI. In this study, we investigated the effects of body position and AE on the temporal characteristics of MI in people with LLA. Ten participants with LLA (mean age = 59.6 ± 13.9 years, four females) and ten gender- and age-matched healthy control participants (mean age = 60.1 ± 15.4 years, four females) were included. They performed two locomotor-related tasks (a walking task and the Timed Up and Go task) while MI times were measured in different conditions (in congruent/incongruent positions and before/after AE). We showed that MI times were significantly shorter when participants imagined walking in a congruent-standing position compared to an incongruent-sitting position, and when performing MI after actual walking compared to before, in both groups. Shorter MI times in the congruent position and after AE suggest an improvement of MI's temporal accuracy (i.e. the ability to match AE time during MI) in healthy individuals but not in the LLA group.

The Immediate Effect of Informational Manual Therapy for Improving Quiet Standing and Bodily Pain in University Population.

BACKGROUND: The Informational Manual Therapy (IMT) is a therapeutic touch. This study aims to assess the effect of IMT on quiet standing, pain and health status in university population. METHODS: An experiment was conducted on subjects utilizing a comparative paired analysis both before and after the intervention. One IMT session was performed on 57 healthy individuals aged from 18 to 65 years. The primary outcome was quiet standing assessed by the Satel 40 Hz stabilometric force platform. Secondary outcomes were bodily pain assessed by the 36-Item Short Form Survey (SF-36) and health status by EQ-5D-3L. The primary outcome was evaluated before and immediately after treatment. RESULTS: The individuals were divided into 3 age groups, 18-35 (52.6%), 35-50 (29.8%) and 51-65 (17.6%). Statistically significant differences were immediately observed after the session ended when comparing the pre-post quiet stance scores in a number of length parameters: L, Lx, Ly and stabilometry amplitude on Y-axis with eyes open and closed. Significant differences were also found when testing bodily pain (SF-36) and anxiety (5Q-5D-3L). CONCLUSION: One session of IMT produced positive effects when testing quiet standing with eyes open and eyes closed, as well as a significant reduction in pain and anxiety for those tested. Further research is suggested.

Comparison of Pelvic Tilt Before and After Hip Flexor Stretching in Healthy Adults.

OBJECTIVE: The purpose of this study was to assess the association between hip flexor length and pelvic tilt or lumbar lordosis by quantifying the effect of stretching on pelvic tilt and lumbar lordosis. METHODS: We quantified pelvic tilt and lumbar lordosis before and after a single session of passive hip flexor stretching in a sample of 23 male participants. Changes in hip flexor length were also characterized, using a Thomas test protocol to measure passive hip extension in supine lying. We investigated both the mean effect of the stretching protocol and potential correlations between changes in passive hip extension and changes in pelvic tilt or lumbar lordosis. RESULTS: Following the stretching protocol, there was a mean increase of 2.6° (P < .001) in passive hip extension and a corresponding mean reduction of 1.2° (P < .001) in anterior pelvic tilt. However, there was no change in lumbar lordosis, nor were there any meaningful correlations between change in passive hip extension and change in pelvic tilt or lumbar lordosis. CONCLUSION: The results suggest that hip muscle stretching may lead to immediate reductions in pelvic tilt during relaxed standing. Such stretching programs could play an important role in interventions designed to improve standing postural alignment.

Reliability of postural control during double-leg standing in subjects with nonspecific chronic low back pain: Dual-task paradigm and manipulated visual and somatosensory inputs.

BACKGROUND: The aim of this study is to evaluate the test-retest reliability of the Center of Pressure (COP) parameters in quiet double-leg standing in subjects with Non-Specific Chronic Low Back Pain (NSCLBP) during dual taking associated with manipulated visual and somatosensory inputs. MATERIALS AND METHODS: In this observational cross-sectional study, the static balance of thirty NSCLBP patients were assessed during a double-leg stance by using the force platform. Subjects were accosted by manipulated somatosensory and visual inputs during dual taking in eight different conditions (with and without vibration, eyes-open and eyes-closed, and with and without auditory Stroop test). The COP parameters were recorded as follows: range sideways and range fore-aft as well as mean velocity and area variables. The cognitive task parameters included the reaction time and error ratio. The intra-class correlation coefficient (ICC) was computed to assess the intersession reliability of COP parameters. RESULTS: in intersession, range sideways, range fore-aft, and mean velocity measures possessed moderate to high ICC, but area owned high ICC only in one condition (double-leg stance, eyes-close, with vibration, and with auditory Stroop test). Notably, other conditions had low ICC, and moderate to high and low to very high ICC were reported for reaction time and error ratio. CONCLUSION: Among the parameters studied in the present study, the mean velocity measure seems to be the most reliable variable of postural control in the subjects with NSLBP especially in more challenging conditions, i.e., quiet double-leg standing with eyes closed and adding vibratory inputs during dual-tasking.

Myoelectric activity of the gastrocnemius during plantar flexion in a standing versus seated position and with a neutral or dorsiflexed ankle: A pilot study.

OBJECTIVE: The purpose of this study was to investigate the surface electromyographic (EMG) activity of the medial (GM) and lateral (GL) heads of the gastrocnemius muscle during plantar flexion performed in standing or seated positions, and with a neutral or dorsiflexed ankle. INTRODUCTION: The tríceps surae (gastrocnemius and soleus) is an essential muscle group that promotes propulsion during walking, running and tasks of daily living. METHODS: Ten male volunteers (24.5 ± 3.6 years, weight: 75.8 ± 10 kg; height: 1.74 ± 0.07 m) performed ten repetitions of plantar flexion under four different conditions: a) standing position (SP); b) standing position with passive stretch of the gastrocnemius muscle (SPS); c) seated with the knee flexed (KF); d) seated with the knee flexed and a passive stretch of the gastrocnemius (KFS). RESULTS: The muscle activity expressed as the root mean square (RMS) was significantly higher for the GL in the SPS versus the SP condition, while there was no difference for the GM between conditions. However, for the KF condition, GM activity was significantly higher versus the KFS condition, which was not verified for the GL. CONCLUSIONS: Therefore, the standing position with passive stretching of the triceps surae may be more efficient in increasing the myoelectric activity of the GL. However, the sitting position without passive stretching promoted greater GM muscle recruitment. The length/tension relationship of gastrocnemius could be used as a prescription variable during rehabilitation or conditioning programs.

Perspectives of individuals with chronic spinal cord injury following novel balance training involving functional electrical stimulation with visual feedback: a qualitative exploratory study.

BACKGROUND: Individuals with an incomplete spinal cord injury (iSCI) are highly susceptible to falls during periods of walking or standing. We recently reported the findings of a novel intervention combining functional electrical stimulation with visual feedback balance training (FES + VFBT) on standing balance abilities among five individuals with motor iSCI. However, the previous publication did not report the perceived impact of the intervention on the participants' lives. In this report, the experiences of these five individuals with incomplete spinal cord injury (iSCI) who had recently completed the four-week balance training program are described. METHODS: Five individuals with a motor iSCI took part in this study. Each individual was at least 12 months post-injury, capable of unassisted standing for 60 s and had a Berg Balance Scale Score < 46. Participants completed twelve sessions of a novel balance intervention combining closed-loop functional electrical stimulation with visual feedback balance training (FES + VFBT). Participants received visual feedback regarding their centre of pressure position as they completed balance-training exercises while FES was applied to the ankle plantarflexors and dorsiflexors bilaterally. Semi-structured interviews were conducted after completion of the balance training intervention and eight-weeks post-training to understand participant's experiences. Categories and themes were derived from the transcripts using conventional content analysis. RESULTS: Three themes were identified from the collected transcripts: (1) Perceived benefits across International Classification of Functioning, Disability and Health levels; (2) Change in perceived fall risk and confidence; (3) Motivation to keep going. CONCLUSIONS: Participation in the FES + VFBT program resulted in perceived benefits that led to meaningful improvements in activities of daily living. Following completion of the training, individuals felt they still had the capacity to improve. Individuals felt they had increased their balance confidence, while a few participants also reported a decrease in their risk of falling. The inclusion of qualitative inquiry allows for the evaluation of the meaningfulness of an intervention and its perceived impact on the lives of the participants. TRIAL REGISTRATION: NCT04262414 (retrospectively registered February 10, 2020).

Modulation of intracortical inhibition during physically performed and mentally simulated balance tasks.

PURPOSE: Action observation (AO) during motor imagery (MI), so-called AO + MI, has been proposed as a new form of non-physical training, but the neural mechanisms involved remains largely unknown. Therefore, this study aimed to explore whether there were similarities in the modulation of short-interval intracortical inhibition (SICI) during execution and mental simulation of postural tasks, and if there was a difference in modulation of SICI between AO + MI and AO alone. METHOD: 21 young adults (mean ± SD = 24 ± 6.3 years) were asked to either passively observe (AO) or imagine while observing (AO + MI) or physically perform a stable and an unstable standing task, while motor evoked potentials and SICI were assessed in the soleus muscle. RESULT: SICI results showed a modulation by condition (F2,40 = 6.42, p = 0.009) with less SICI in the execution condition compared to the AO + MI (p = 0.009) and AO (p = 0.002) condition. Moreover, switching from the stable to the unstable stance condition reduced significantly SICI (F1,20 = 8.34, p = 0.009) during both, physically performed (- 38.5%; p = 0.03) and mentally simulated balance (- 10%, p < 0.001, AO + MI and AO taken together). CONCLUSION: The data demonstrate that SICI is reduced when switching from a stable to a more unstable standing task during both real task execution and mental simulation. Therefore, our results strengthen and further support the existence of similarities between executed and mentally simulated actions by showing that not only corticospinal excitability is similarly modulated but also SICI. This proposes that the activity of the inhibitory cortical network during mental simulation of balance tasks resembles the one during physical postural task execution.

Lumbar Spine Kinematics in Asymptomatic People When Changing Body Position From Sitting to Standing.

OBJECTIVE: The purpose of this study was to assess the lumbar spine kinematics in 3 movement axes in asymptomatic individuals in the sit-to-stand (STS) movement performed in a habitual, flexion, or extension manner. METHODS: There were 30 participants (16 women, 14 men), aged 23 to 37 years. Each participant performed an STS test. We registered the total time of the STS movement and the maximum acceleration of the lumbar spine in the vertical, anteroposterior, and mediolateral axes. The examination of the movement pattern was performed with the use of a BTS G-sensor device. RESULTS: The highest movement dynamics in the lumbar spine were observed during the STS performed in a habitual manner in the 3 axes (P < .01). The lowest movement dynamics ere associated with the extension STS pattern. The flexion pattern differed from the habitual one in total performance time in both groups (P < .01). There were no significant differences in kinematic lumbar spine between sexes. CONCLUSION: The kinematics of the STS movement for asymptomatic individuals were characterized by significant variability in the maximum acceleration in the 3 axes. The highest movement dynamics were observed during the STS performed in a habitual manner, and the lowest dynamics with the extension pattern of STS.

Effects of transcranial direct current stimulation (tDCS) on posture, movement planning, and execution during standing voluntary reach following stroke.

BACKGROUND: Impaired movement preparation of both anticipatory postural adjustments and goal directed movement as shown by a marked reduction in the incidence of StartReact responses during a standing reaching task was reported in individuals with stroke. We tested how transcranial direct current stimulation (tDCS) applied over the region of premotor areas (PMAs) and primary motor area (M1) affect movement planning and preparation of a standing reaching task in individuals with stroke. METHODS: Each subject performed two sessions of tDCS over the lesioned hemisphere on two different days: cathodal tDCS over PMAs and anodal tDCS over M1. Movement planning and preparation of anticipatory postural adjustment-reach sequence was examined by startReact responses elicited by a loud acoustic stimulus of 123 dB. Kinetic, kinematic, and electromyography data were recorded to characterize anticipatory postural adjustment-reach movement response. RESULTS: Anodal tDCS over M1 led to significant increase of startReact responses incidence at loud acoustic stimulus time point - 500 ms. Increased trunk involvement during movement execution was found after anodal M1 stimulation compared to PMAs stimulation. CONCLUSIONS: The findings provide novel evidence that impairments in movement planning and preparation as measured by startReact responses for a standing reaching task can be mitigated in individuals with stroke by the application of anodal tDCS over lesioned M1 but not cathodal tDCS over PMAs. This is the first study to show that stroke-related deficits in movement planning and preparation can be improved by application of anodal tDCS over lesioned M1. Trial registration ClinicalTrial.gov, NCT04308629, Registered 16 March 2020-Retrospectively registered, https://www.clinicaltrials.gov/ct2/show/NCT04308629.

Impairments and Compensations of Static Balance and Plantar Load Distribution in Patients With Chronic Stroke: An Observational Study.

OBJECTIVES: The purpose of this study was to explore impairment and compensation characteristics of static balance and plantar load distribution in patients with chronic stroke. METHODS: We recruited 68 patients who had chronic stroke who could stand independently (stroke group) and 30 healthy individuals (control group) with the Zebris FDM platform. Static balance parameters, including center of pressure (COP) ellipse sway area, COP path length, and angle-θ between y and major axis, were compared between 2 groups under standard standing posture. In the stroke group, balance parameters were re-tested under their preferring standing posture. Plantar load distribution was also assessed. Another 8 patients with chronic stroke who could not stand independently and had to rely on a crutch were enrolled to analyze the characteristics of balance compensation. RESULTS: In the stroke group, the ellipse sway area, COP path length, and angle-θ were significantly larger than those of the control group. Sixty-one (89.7%) patients preferred standing with the affected foot outward-forward supporting, and their preferring standing balance was better than that of standard standing. All patients who could not stand independently tended to compensate for balance with a crutch supporting laterally and also preferred standing with a typical posture- the affected foot was outward-forward. CONCLUSIONS: In patients post stroke, static balance is impaired mainly at the lateral direction, and patients commonly locate the crutch laterally for compensation of lateral balance. Patients preferred standing with the affected foot outward-forward supporting, and their preferring standing balance was better than that of standard standing, which challenged the necessity of training standing symmetrically.