Anteroposterior Velocity Research Articles

Stabilometric changes due to exposure to firearm noise in the Brazilian Army

Success in precision activities such as shooting depends on the subtle control of body motion. To analyze the influence on stabilometric signal responses for the motor task of aiming a pistol with different cognitive demands and levels of exposure to high sound pressure in Brazilian Army personnel. This cross-sectional analytical study used stabilometry to quantify the behavior of the body during motor, cognitive, and auditory tasks. Twenty-five volunteers recruited to participate in the study completed a questionnaire, underwent anthropometric evaluation and cinemetry, and scored the perceived difficulty during exposure to a sound pressure of 132 dB while using protective equipment. A significant increase in the displacement (p=0,02), anteroposterior amplitude (p=0,01), anteroposterior velocity (p=0,01), and the perceived difficulty scale (p=0,03) between Situation 1 (aiming without other cognitive action or environmental noise) and Situation 3 (shooting noise and progressive counting) was confirmed. number of shots heard). Correlation between the perceived difficulty scale and the variables of displacement (p=0,01), anteroposterior amplitude (p=0,01), area (p=0,006) and anteroposterior mean frequency (p=0,01) were observed. The accuracy of aiming events correlated with the median lateral median frequency (p=0,02). Stabilometric signals demonstrated increased total displacement, anteroposterior amplitude, and anteroposterior velocity in the presence of high sound pressure levels. These results indicate the need for future studies to investigate the underlying mechanisms of possible vestibular damage induced by noise.

Posturographic Analysis in the Elderly with and without sensorineural Hearing Loss.

Introduction Sensorineural hearing loss (SNHL) is a serious public health problem. Some evidence suggests a significant relationship between SNHL and balance disorders. The inability to maintain balance associated with SNHL while standing further increases the risk of falls among older people. Objective To investigate the association between SNHL on the postural balance in elderly individuals of both genders. Methods The sample consisted of 247 (166 women) physically independent elderly individuals, (mean age = 68.4 ± 6.0). The instruments used were the anamnesis and the pure tone audiometry for hearing loss, and for balance a force platform based in measures of center of pressure area and of sway velocity in the anteroposterior and mediolateral directions. Results Presence of hearing loss (HL) was observed in 68% of the participants. We observed a significant association between SNHL and characteristics of balance between the groups with and without HL for center of pressure (COP) area ( p = 0.010), anteroposterior velocity ( p = 0.001) and mediolateral velocity ( p = 0.020). There was a significant difference between the gender groups for center of pressure area ( p = 0.004), anteroposterior velocity ( p = 0.001) and mediolateral velocity ( p = 0.001) with better performance in the female group. Amongst men, there was a difference between the ones with HL and those without it, for COP area ( p = 0.049). Conclusion In the present study, elderly individuals with SNHL exhibited more instability on the postural balance, and elderly men presented worse results in the test.

Effects of Ankle Angular Position and Standing Surface on Postural Control of Upright Stance.

The purpose of the study was to investigate the effects of ankle angular position and standing surface type on static upright balance. Ten young adults stood on a force platform or on a firm wedge that induced 15° of either dorsiflexion or plantarflexion. In addition, a piece of foam was placed on top of the force platform and on the wedge. The center of pressure distance and velocity in the anteroposterior and mediolateral directions were calculated. Significantly larger magnitudes in most of the investigated variables were seen while standing with ankles in the dorsiflexion when compared with standing with the ankle joints in a natural position (p < .05). Plantarflexion increased the center of pressure anteroposterior velocity by 87% when compared with a natural stance (p < .05). Standing on the foam surfaces resulted in increases in all of the center of pressure measures by an average of 38% in all of the ankle conditions.

Static balance in older adults with chronic obstructive pulmonary disease undergoing pulmonary rehabilitation

OBJECTIVE: To compare balance between older adults with and without chronic obstructive pulmonary disease (COPD) in tasks involving proprioceptive changes and respiratory muscle load, and to investigate the association between balance, functional capacity, and peripheral and respiratory muscle strength. METHODS: Fourteen older adults with COPD undergoing pulmonary rehabilitation and nine older adults without pulmonary disease were evaluated for static balance on a force platform under four conditions: eyes open, eyes closed, eyes closed on foam, and eyes open with respiratory overload. Differences between groups, among conditions and group/condition interactions, were tested using two-way ANOVA. Associations were explored using Pearson’s correlation coefficient. RESULTS: No differences in the posturographic variables were found in the group/condition interactions (p ≥ 0.23). The COPD group exhibited greater total displacement (F = 8.79, p = 0.003), mediolateral sway (F = 4.01, p = 0.04) and anteroposterior velocity (F = 4.28, p = 0.04) in the group effect analysis. Significant differences were found between eyes closed on foam and other conditions for all posturographic variables: anteroposterior sway (F = 13.39), mediolateral sway (F = 28.58), total displacement (F = 59.4), area (F = 37.68), anteroposterior velocity (F = 26.42), and mediolateral velocity (F = 33.29), in the condition effect analysis (p &lt; 0.001, post-hoc). In the COPD group, significant correlations were found between the Glittre-ADL test, anteroposterior sway (r = 0.68, p = 0.01), and anteroposterior velocity (r = 0.67, p = 0.009); the 6MWT was also correlated with anteroposterior velocity (r = 0.59, p = 0.03). CONCLUSION: Older adults with COPD present balance deficits compared to healthy individuals. The unstable surface caused greater postural instability compared to other conditions in both groups. Impaired balance was associated with reduced physical function and exercise capacity.

Postural Stability in Obese Preoperative Bariatric Patients Using Static and Dynamic Evaluation

Introduction: Globally, 300 million adults have clinical obesity. Heightened adiposity and inadequate musculature secondary to obesity alter bipedal stance and gait, diminish musculoskeletal tissue quality, and compromise neuromuscular feedback; these physiological changes alter stability and increase injury risk from falls. Studies in the field focus on obese patients across a broad range of body mass indices (BMI >30 kg/m²) but without isolating the most morbidly obese subset (BMI ≥40 kg/m²). We investigated the impact of obesity in perturbing postural stability in morbidly obese subjects elected for bariatric intervention, harboring a higher-spectrum BMI. Subjects and Methods: Traditional force plate measurements and stabilograms are gold standards employed when measuring center of pressure (COP) and postural sway. To quantify the extent of postural instability in subjects with obesity before bariatric surgery, we assessed 17 obese subjects with an average BMI of 40 kg/m² in contrast to 13 nonobese subjects with an average BMI of 30 kg/m². COP and postural sway were measured from static and dynamic tasks. Involuntary movements were measured when patients performed static stances, with eyes either opened or closed. Two additional voluntary movements were measured when subjects performed dynamic, upper torso tasks with eyes opened. Results: Mean body weight was 85% (p < 0.001) greater in obese than nonobese subjects. Following static balance assessments, we observed greater sway displacement in the anteroposterior (AP) direction in obese subjects with eyes open (87%, p < 0.002) and eyes closed (76%, p = 0.04) versus nonobese subjects. Obese subjects also exhibited a higher COP velocity in static tests when subjects’ eyes were open (47%, p = 0.04). Dynamic tests demonstrated no differences between groups in sway displacement in either direction; however, COP velocity in the mediolateral (ML) direction was reduced (31%, p < 0.02) in obese subjects while voluntarily swaying in the AP direction, but increased in the same cohort when swaying in the ML direction (40%, p < 0.04). Discussion and Conclusion: Importantly, these data highlight obesity’s contribution towards increased postural instability. Obese subjects exhibited greater COP displacement at higher AP velocities versus nonobese subjects, suggesting that clinically obese individuals show greater instability than nonobese subjects. Identifying factors contributory to instability could encourage patient-specific physical therapies and presurgical measures to mitigate instability and monitor postsurgical balance improvements.

Can Individuals with Down Syndrome Benefit from Hippotherapy? An Exploratory Study on Gait and Balance

ABSTRACT Purpose: To evaluate whether a hippotherapy protocol may influence balance and gait in patients with Down Syndrome (DS). Methods: Fifteen male patients affected by DS underwent a 6-month hippotherapy protocol. Stabilometric, baropodometric, and gait assessments were performed at baseline (T0) and at the end of the treatment (T1). Results: At baseline, DS patients showed a low bilateral hind foot pressure percentage at the baropodometric analysis, a high center of pressure area in the closed-eye condition, a high center of pressure sway in open- and closed-eyes recordings, a high medio-lateral and antero-posterior velocity oscillations in the closed eye condition, and a reduced step-length and velocity. After the 6-month, hippotherapy protocol, DS patients had a significant bilateral higher hindfoot pressure percentage. The stabilometric analysis revealed a lower center of pressure area in the closed-eye condition, and a significantly reduced center of pressure sway in open- and closed-eyes recordings. In addition, DS patients showed lower medio-lateral and antero-posterior velocity oscillations in the closed eye condition. Finally, hippotherapy significantly improved step length and velocity. Conclusions: This pilot study demonstrates that hippotherapy determines functional improvement in gait speed, width, bilateral symmetry, and balance in DS.

Analysis of the weight of school backpack with double strapson the postural control of children

To investigate the influence of the weight of school backpacks on postural control of children. Cross-sectional study in healthy children aged eight years old. The postural control was evaluated on the force plate (FP) and the Timed Up and Go test (TUG) in three distinct conditions: without backpack (WB), and the backpack adjusted with 5% (.5) and 10% (. 10) of body mass. 90 children were evaluated, and 80% of them used backpacks with two shoulder straps, and 16% of the children carried over 10% of their body mass in the backpacks. Regarding the postural control with load on school backpack, there was increase in the sway area of the center of pressure (A-COP.WB = 6.92 cm²; A-COP.5 = 8.39 cm²; A-COP.10 = 7.96 cm²) and time, in seconds, the performance of the TUG (TUG.WB = 4.75 s; TUG.5 = 4.99 s; TUG.10 = 5.06 s), with statistically significant difference between the loads (p = 0.0001; p = 0.0005), respectively. The anteroposterior (VELAP.SM = 2.41cm s-1; VELAP.5 = 2.30 cm s-1; VELAP.10 = 2.22 cm s-1; p = 0.0001) and mediolateral velocity (VELML.WB = 2.38 cm s-1; VELML.5 = 2.28 cm s-1; VELML.10 = 2.20 cm s-1; p = 0.0001) had a decrease in the median values with statistically significant difference in different conditions. School backpack load increased the COP area, the time of the TUG and modified the response mechanisms. Therefore, loads up to 5% of body mass imposed on school backpack have negatively influenced the postural control.

Effects of Rapid Weight Loss on Balance and Reaction Time in Elite Judo Athletes.

To examine the effects of rapid and progressive weight loss (RWL and PWL) on balance, reaction time, and strength in a group of elite judo athletes. A total of 38 female and male judo athletes (age = 20.6 [2.6]y) completed balance, reaction-time, and strength assessments 1 wk prior to an official weigh-in (pretest) and immediately after the weigh-in (posttest). The athletes were divided into 3 groups, 1 control group who maintained regular training and eating habits, 1 experimental group who engaged in PWL (<3% reductions in body mass), and a second experimental group who used RWL techniques (>3% reductions in body mass). The RWL group showed significant decreases (P < .05) in balance performance (ellipse area: 4.83 [0.87] vs 6.31 [1.39]mm2 with eyes closed; mean mediolateral velocity: 2.07 [0.2] vs 2.52 [0.45]mm·s-1 with eyes closed; and mean anteroposterior velocity: 2.25 [0.20] vs 2.51 [0.32]mm·s-1 with eyes open and 2.44 [0.26] vs 3.06 [0.56]mm·s-1 with eyes closed) and reaction time (0.38 [0.04] vs 0.42 [0.06]s) with no changes in strength from pretesting to posttesting. The athletes in the PWL and control groups maintained performance in all variables. These findings demonstrate negative effects on perceptual motor-skill performance in judo athletes engaging in RWL strategies prior to competition.

Characterizing postural oscillation in children and adolescents with hereditary sensorimotor neuropathy.

Charcot Marie Tooth disease (CMT) has negative functional impact on postural control of children; however, it has not been widely studied. Stabilometry can provide insights about postural control and guide preventive interventions in immature perceptual and musculoskeletal systems as those seen in children with CMT. This cross-sectional study aimed to identify and interpret stabilometric variables that reflect the postural control of children with CMT. 53 subjects (age 6–17) were assigned to one of the two groups: CMT (15 males and 14 females with CMT) or Control (13 males and 11 females healthy). Quiet standing was tested in different conditions: with open and closed eyes on regular surface (open-regular, closed-regular) and foam surface (open-foam, closed-foam) using a force platform. The minimum of 2 and maximum of 3 trials of 30 seconds for each test condition provided the classical stabilometric variables and Romberg Quotient (RQv). CMT group showed increase of confidence ellipse area, mean velocity, mediolateral and anteroposterior velocities associated with decreased mean body oscillation frequency, as the complexity of tasks increased. CMT postural deficit was identified by greater and faster sway associated with these lower frequencies, when compared to Control.

The postural stability of children with foetal alcohol spectrum disorders during one-leg stance: A feasibility study.

BackgroundPostural control may be impaired in children with foetal alcohol spectrum disorders (FASD). The study assessed the protocol feasibility in terms of (1) recruiting children with FASD in a rural, small town; (2) using the measurement instruments in a real-life setting; (3) the one-leg standing (OLS) task and (4) presenting preliminary results on postural stability of children with and without FASD.MethodsNine-year-old children diagnosed with and without FASD were invited to participate. Twenty-eight children performed OLS. Feasibility outcomes included recruitment, measurement instrument use and task instruction. Postural stability outcomes included standing duration, centre of pressure (COP) and body segment acceleration.ResultsParticipants recruitment was feasible in terms of the (1) ability to sample a reasonable participant number in a rural town setting and the capacity to increase the sample size if more schools are included in the sampling frame and (2) use of assent and consent forms that were appropriate for this population. The measurement instruments were user-friendly, cost-effective and time-efficient. Instructions for the task require amendment to address foot placement of the non-weight–bearing leg. There was a significant difference between cases and controls on mean COP velocity (p = 0.001) and the pelvis segment acceleration in the mediolateral direction (p = 0.01) and the anteroposterior direction (p = 0.027). The control children took longer to achieve postural control. The girls demonstrated a significant difference for the COP anteroposterior displacement (p = 0.008) and velocity (p = 0.049).ConclusionsThe recruitment of children with and without FASD in a rural, small town and the administration of measurement instruments in a real-life, school-based setting was feasible. However, the verbal instructions for the task require revision. The male control group took longer to achieve postural control because the task was performed differently between the two groups. However, the case girls were slower to achieve postural control than control girls though performing the task similarly.

Effects of astigmatic axis orientation on postural stabilization with stationary equilibrium

We evaluated 15 healthy participants by assessing their maintenance of postural control while standing on a platform stabilometer for 1 min under the following conditions: eyes open; eyes open with + 3.00 D on both eyes on same directions (45, 90, 135, 180 degree axis); right eye on 45 degree axis and left eye on 135 degree axis (inverted V-pattern), and right eye on 135 degree axis and left eye on axis 45 degree axis (V-pattern). The differences in the linear length, area and maximum velocity of center of pressure during postural control before and after the six types of positive cylinder-oriented axes were analyzed. Comparing the antero-posterior lengths and antero-posterior maximum velocities, there were significant differences between the V-pattern condition and the six other conditions. Astigmatic defocus in the antagonistic axes conditions, particularly the V-pattern condition, affects postural control of antero-posterior sway (143/150).

Effects of sling exercise on postural sway in post-stroke patients.

[Purpose] To examine the effects of sling exercise on the balance of post-stroke patients. [Subjects and Methods] A total of 18 post-stroke patients (13 men; mean age, 55.3 years) were recruited, and randomly assigned them into sling exercise (n=10) and control exercise (n=8) groups. The Good Balance System was used for measurement of velocity (anteroposterior and mediolateral, mm/s), velocity moment (mm2/s) of the movement of the center of pressure, and distance (anteroposterior and mediolateral, mm) between the center of pressure and the center point. The changes in mediolateral velocity, anteroposterior velocity, and velocity moment were compared between two groups in addition to the comparison of distance between the center of pressure and the center point of postural sway. [Results] The sling exercise group showed more significant improvements in anteroposterior velocity, mediolateral velocity, velocity moment, anteroposterior distance, and mediolateral distance than the control exercise group. [Conclusion] Sling exercise improved post-stroke balance performance and could be used as a therapeutic strategy to improve post-stroke functional recovery.

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.

Effects of Freezing of Gait and Visual Information on the Static Postural Control Ability in Patients with Parkinson's Disease

Objective: The purpose of this study was to analyze the effects of freezing of gait and visual information on the static postural control ability in patients with Parkinson``s Disease (PD) during the bipedal stance with feet together. Method: This study included a total of 36 patients with PD; the freezer group included 17 PD patients (age: 69.3±6.2 yrs, height: 159.6±9.0 cm, weight: 63.4±9.78 kg) and the nonfreezer group included 19 PD patients (age: 71.4±5.6 yrs, height: 155.8±7.1 cm, weight: 57.7±8.6 kg). Static postural control ability was analyzed using variables of center of pressure (COP) and dividing by mediolateral, anteroposterior, and integration factors during a bipedal stance with the eyes open and closed. Results: Freezers and nonfreezers showed increases in anteroposterior velocity, mediolateral velocity, averaged velocity, and mediolateral 95% edge frequency when visual information was blocked. Additionally, freezers had greater anteroposterior range, 95% confidence ellipse area, and COP anteroposterior mean position than nonfreezers. Conclusion: Freezers and nonfreezers showed a reduction in static postural control ability when visual information was blocked. Additionally, the results of this study found a significant difference in static postural control ability between freezers and nonfreezers with PD. In particular, anteroposterior range, 95% confidence ellipse area, and COP anteroposterior mean position might be used to distinguish between freezers and nonfreezers with PD.

Altered dynamic postural control during gait termination following concussion

Impaired postural control is a cardinal symptom following concussion. Planned gait termination (GT) is a non-novel, dynamic task that challenges postural control in individuals with neurological deficits, and it could be an impactful measure for identifying dynamic postural control impairments following concussion. Therefore, the purpose of this study was to assess acute post-concussion dynamic postural control utilizing a planned GT task. The concussion participants (n=19, age: 19.0±0.8years, height: 177.0±10.1cm, weight: 83.3±20.0kg) completed five planned GT trials during preseason baseline testing (Baseline) and on Day 1 post-concussion (Day-1). Healthy control participants (n=19, age: 20.4±1.2years, height: 173.8±8.9cm, weight: 80.2±17.6kg) completed the same trials a week apart. The dependent variables of interest included COP displacement and velocity in the mediolateral (ML) and anteroposterior (AP) axes during the three phases (braking, transitional, stabilization) of planned GT. There were significant interactions observed in both the braking ML and transitional AP displacement (p=0.042, p=0.030) and velocity (p=0.027, p=0.030). These results suggest a conservative post-concussion motor control strategy during planned GT. Further, these results support the use of dynamic postural control tasks as measures of post-concussion impairments.

EEG-biofeedback Intervention Improves balance in Stroke Survivor

Postural instability while performing daily activity is main problem to individuals with stroke. Increased postural sway is related to postural instability resulting in falls. Internal and external foci of attention were used to decline postural sway of individuals with neurological deficits. Electroencephalogram (EEG) biofeedback may be efficiency device for clinical training which external focus of attention. The purpose of this study is to explore whether external (EEG biofeedback) and internal foci of attention with unstable surface would affect postural sway in chronic stroke. Twenty-one hospitalized people with stroke were participated. Postural sway was measured at three conditions randomly while participants stood on the force platform with unstable surface. The conditions were control (quiet stand), internal focus of attention (focus on the own body), and external focus of attention (focus on the outside of body by EEG biofeedback). The external focus of attention resulted in less postural sway relative to both the internal focusof attention and control conditions. There was no significant difference between the external and internal foci of attention on anteroposterior sway velocity. In conclusions, the results are suggested that external focus of attention better to postural control than internal focus of attention or control condition during standing for individuals with stroke. The outcomes have possibly important for intervention by clinicians and the reduction of postural instability in stroke patients.

The efficacy of plantar stimulation on human balance control

Aim: The aim of this study was to evaluate the body sway using firm, foam, and firm textured surfaces on 17 young adults. Method: Displacement of center of pressure (CoP), anteroposterior velocity (VA/P), and mediolateral velocity (VM/L) were measured. Data: The data showed a significant decrease of CoP, VA/P, and VM/L between support surfaces and vision. Results: The results showed that, differently from the firm and foam, the textured surface is able to increase the plantar feedback to maintaining postural control.

Novel use of the Wii Balance Board to prospectively predict falls in community-dwelling older adults

BackgroundThe Wii Balance Board has received increasing attention as a balance measurement tool; however its ability to prospectively predict falls is unknown. This exploratory study investigated the use of the Wii Balance Board and other clinical-based measures for prospectively predicting falls among community-dwelling older adults. MethodsSeventy-three community-dwelling men and women, aged 60–85years were followed-up over a year for falls. Standing balance was indexed by sway velocities measured using the Wii Balance Board interfaced with a laptop. Clinical-based measures included Short Physical Performance Battery, gait speed and Timed-Up-and-Go test. Multivariable regression analyses were used to assess the ability of the Wii Balance Board measure to complement the TUG test in fall screening. FindingsIndividually, the study found Wii Balance Board anteroposterior (odds ratio 1.98, 95% CI 1.16 to 3.40, P=0.01) and mediolateral (odds ratio 2.80, 95% CI 1.10 to 7.13, p=0.03) sway velocity measures predictive of prospective falls. However, when each velocity measure was adjusted with body mass index and Timed-Up-and-Go, only anteroposterior sway velocity was predictive of prospective falls (odds ratio 2.21, 95% CI 1.18 to 4.14). A faster anteroposterior velocity was associated with increased odds of falling. Area-under-the-curves for Wii Balance Board sway velocities were 0.67 and 0.71 for anteroposterior and mediolateral respectively. InterpretationThe Wii Balance Board-derived anteroposterior sway velocity measure could complement existing clinical-based measures in predicting future falls among community-dwelling older adults. Trial registrationAustralian New Zealand Clinical Trials Registry number: ACTRN12610001099011.

Correlación entre el control postural y neuromuscular con cuestionarios de percepción funcional en deportistas con inestabilidad de tobillo

ObjectiveTo determine the correlation between postural and neuromuscular control assessments and questionnaires of subjective perception in athletes with functional ankle instability. Material and methodsA descriptive study with a correlational design was performed. Ten male athletes participated. Postural control was measured from the displacement of the center of pressure (COP) in the medio-lateral (ML) and anteroposterior (AP) directions. The following variables were obtained: area, ML variability, AP variability, ML velocity and AP velocity. Bipodal and unipodal measurements with opened eyes (OE) and closed eyes (CE) were made. Muscle reaction time of peroneus longus (PL), peroneus brevis (PB) and tibialis anterior (TA) was recorded with surface electromyography in sudden ankle inversion test. Functional ankle perception questionnaires were administered: AJFAT and CAIS. The statistical analysis was performed with the Pearson Test. Significance level was established a priori at P<0.05. ResultsThere was a moderate negative correlation between AJFAT with PL muscle (r=-0.64, P=0.049) and with the CAIS and PL muscle (r=-0.65, P=0.044). Strong negative correlations were observed between the AJFAT questionnaire and COP area in unipodal EC (r=-0.75, P=0.013) and between the CAIS questionnaire and COP velocity ML in and unipodal EC (r=-072, P=0.019). ConclusionsThe use of questionnaires applied in this study could be useful in assessing the functional limitations of patients with functional ankle instability, favoring the physiotherapy approach to these patients.

Gait characteristics of adults with Down syndrome explain their greater metabolic rate during walking

The altered gait patterns of adults with Down syndrome (DS) may contribute to their higher net metabolic rate (net-MR) during walking than adults without DS, leading to mobility limitations. This study examined the extent to which gait characteristics explain differences in net-MR during walking between adults with and without DS. Fifteen adults with DS (27±8 years) and 15 adults without DS (28±6 years) completed two testing sessions in which expiratory gases and kinematic data were collected, respectively, during treadmill walking. Participants walked at six, randomly-presented dimensionless speeds, ranging from slow to fast. Hierarchical and stepwise regressions were used to determine the proportion of the variance in net-MR explained by gait variables that differed between groups, after controlling for variance due to walking speed. Positive work rate, the range of the body center of mass (COM) mediolateral position and its square, variability in the time-course of COM anteroposterior velocity, and the variability of step length, step width, and step time significantly predicted net-MR (p<.05). These variables collectively explained 73.9% of the variance in net-MR that was explained by DS but not by walking speed. After accounting for shared variance among predictors, step length variability made the greatest unique contribution (10.6%) to the higher net-MR in adults with DS, followed by the range of COM mediolateral motion (6.3%), step width variability (2.8%), and variability in COM anteroposterior velocity (0.7%). Therefore, the gait characteristics of adults with DS appear to largely explain their higher net-MR during walking.