Narrow Base Of Support Research Articles

Postural stability of adults with down syndrome – differences between women and men

ObjectiveThis study aimed to analyse differences in postural stability (PS) between adults with Down syndrome (DS) and adults without DS of the same age and to compare the PS between men and women with DS.MethodsTwenty-six individuals with DS (mean age 38.4 ± 8.7 yrs.) and 26 individuals without DS (mean age 38.8 ± 9.2 yrs.) participated in the study. Postural stability was measured using a pressure sensing platform MobileMat 3140 (Tekscan) in these modifications of the bipedal stance: a. wide base of support with the eyes open (WO); b. wide base of support with the eyes closed (WC); c. narrow base of support with the eyes open (NO). Six parameters of PS were compared in the statistical analysis: centre of pressure (COP) path length, COP excursion front-back, COP excursion left-right, COP velocity average, time to boundary (TTB) front-back, and TTB left-right.ResultsMost PS variables (COP path length, COP excursion left-right, COP velocity average, TTB front-back) indicate significantly lower PS of adults with DS than that of the reference group (p < 0.05). Some PS variables (COP path length and COP velocity average in WC, COP excursion front-back and COP excursion left-right in NO) showed differences between men and women in more demanding conditions, indicating lower PS in men with DS.

The Functional Balance Ability Measure: A Measure of Balance Across the Spectrum of Functional Mobility in Persons Post-Stroke

ObjectiveTo determine whether the measurement properties of an instrument that combines items from the Berg Balance Scale (BBS) and the Functional Gait Assessment (FGA) called the Functional Balance Ability Measure (FBAM) supports measuring balance across the functional mobility spectrum. DesignRetrospective cohort. SettingItem-level data were from an archival research database. ParticipantsAmbulatory individuals (N=93, BBS=50 [29-56], FGA=16 [0-30], Fugl-Meyer Assessment of Lower Extremities=27 [14-34], self-selected walking speed=0.4±0.2 m/s, mean age ± SD, 61.7±11.3y; 30.1% female) with chronic stroke (≥6 months). InterventionsNot applicable. Main Outcome MeasuresUnidimensionality was evaluated with a principal components analysis (PCA) of residuals. FBAM rating-scale characteristics, item hierarchy, item and person fit, and person separation were investigated using the Andrich Rating Scale Model. ResultsPCA findings indicate the FBAM is sufficiently unidimensional. Rating scale structure was appropriate without modifying the original BBS and FGA scoring systems. Item hierarchy aligned with clinical and theoretical predictions (hardest item: FGA-gait with narrow base of support, easiest item: BBS-sitting unsupported). One item (BBS-standing on 1 foot) misfit, however, removal marginally affected person measures and model statistics. The FBAM demonstrated high person reliability (0.9) and 6 people (∼6%) misfit the expected response pattern. The FBAM separated participants into 4 statistically distinct strata, without a floor or ceiling effect. ConclusionsThe FBAM is a unidimensional measure for balance ability across a continuum of functional tasks. Rating-scale characteristics, item hierarchy, item and person fit, and person separation support the FBAM's measurement properties in persons with chronic stroke. Future work should investigate measurement with fewer items and whether the FBAM addresses barriers to adoption of standardized balance measures in clinical practice.

Yoga Balance: Decreasing Fall Risk in Seniors

<h3>Research Objectives</h3> To investigate the effect of yoga in decreasing fall risk for activities of daily living and community mobility in the senior population thru occupational therapy. <h3>Design</h3> Basic yoga poses related to primal movement were selected/ executed with NDT techniques; 1 year. <h3>Setting</h3> Continuing Care Retirement Community(CCRC). <h3>Participants</h3> 10 clients with inclusion criteria of age 80+, live in the CCRC, can include co-morbidities, joint replacements accepted. <h3>Interventions</h3> Example of pose: horse stance was selected because as children we have a wide base of support with hips in external rotation and equine stance. Overtime this integrates to a narrower base of support, external/ internal rotation equalizes, and equine stance becomes plantar. Utilizing poses that follow typical patterns allows for neuro plasticity to engage in a way it has before enhancing the progression of decreased fall risk as it relates to ADL's. Alignment is key when addressing posture and fall risk in occupational therapy as well as in Iyengar yoga. Used handling techniques, visual work (mirror), and verbal cueing. Cues were a combination of OT and yogic cues to create proper alignment. Handling promoted neck retraction, scapular depression/ stabilization, shoulder/ pelvic girdle anterior alignment, and knee/ ankle alignment. <h3>Main Outcome Measures</h3> Tinetti: scores increased by an average of 11 points. <h3>Results</h3> When used as an individual therapeutic intervention yoga postures with NDT regressive handling techniques increases the Tinetti score by an average of 11 points; proving a marked decrease of fall risk for ADL's in seniors. Secondary outcomes that were reported by patients included scoliosis curvature decrease, bladder control improvement, and an increased ability to orgasm. <h3>Conclusions</h3> With an average number of Tinetti score improvement by 11 for the total of 10 clients with no regression this study does prove that yoga is effective in decreasing fall risk in seniors. Due to our results we believe expanded studies utilizing yoga as an individualized intervention during therapy sessions is necessary to promote decreased fall risk in elderly patients. <h3>Author(s) Disclosures</h3> N/A.

Postural Stability Challenges in Narrow Walking after Traumatic Brain Injury

The aim of this study was to evaluate the predictability and complexity of gait under preferred and narrow walking conditions for groups of TBI and age matched control subjects in order to determine if non-linear measures may be appropriate for identifying gait deviations not detected with more routine techniques. Ten participants from each group walked at preferred gait and with a narrow base of support. Center of mass motion was calculated from marker motion recorded with motion capture. Measures of predictability and complexity of center of mass motion were calculated with Recurrence Quantification Analysis. Walking with a narrow base of support resulted in a less predictable center of mass motion (reduced %Determinism) for TBI and control groups (p=0.0019 and p=0.0008, respectively), but no difference was found between groups. For the TBI group, there was a significant decrease in complexity of center of mass motion (lower Entropy, p=0.0038) with narrow base of support compared to preferred walking, but no difference in Entropy was found between groups. These results suggest non-linear measures determined using techniques such as Recurrence Quantification Analysis might have potential to be valid and reliable measurement techniques for predicting gait deviations in future studies.

Muscle Mass and Gait Characteristics in Older Women Fallers vs. Non-Fallers.

Background: Falling is a major public health concern of elderly people. We aimed to determine if lean mass and spatiotemporal gait parameters could predict the risk of falling in elderly women and also study the relationships between lean mass and gait characteristics. Methods: Twenty-four community women were prospectively recruited (mean age, 72.30 ± 5.31 years). Lean mass was measured using dual-energy fan-beam X-ray absorptiometry. Gait characteristics were assessed using spatiotemporal analysis. Fall risks were assessed using the Berg Balance Scale (BBS) and the Falls Efficacy Scale-International. Fall histories were recorded. Appropriate statistical analyses were applied to determine lean mass and gait characteristics in predicting the risk of fall and the associations between lean mass and gait characteristics. Results: There were 14 participants (58.33%) with fall histories. Patients with fall histories had a significantly narrower base of support and lower BBS score. However, only the base of support was significantly associated with fall risk (odds ratio, 0.415; p = 0.022). Lean mass was significantly negatively associated with proportion of swing phase and positively associated with proportions of stance and double-support phases. Conclusion: Fall risk among elderly women can be predicted using base of support, where a narrower base predicts a greater fall risk. Although the lean mass was not related to risk of fall, lean mass is still related to some gait characteristics.

Manifestation of Anxiety in Gait

In the United States, approximately 18% of adults are affected by anxiety. Nearly $42 billion are spent annually in the U.S. toward alleviating this mood disorder. However, only 10% of those with anxiety are receiving appropriate and effective treatment due to lack of identification. The purpose of this study was to identify gait patterns that are correlated with anxiety to improve probability of detection of this mood disorder. Past studies have examined gait and anxiety in Parkinson’s disease or in healthy individuals with induced anxiety. Our study tries to determine identifiable gait patterns that could signify the presence of increased anxiety in those without a diagnosed mood disorder. Participants (N=133, Males=50, Females=83, Age=25.8±7.96, BMI=24.8±3.8) ages 18 to 69 completed a Profile of Mood Survey (POMS) to assess current feelings of anxiety and completed a two‐minute walk around a 6 m track. Gait data was collected utilizing APDM mobility monitors. A backwards linear regression model was utilized to identify gait correlates of anxiety. The model predicted 13.1% of variance (R2=0.215, F= 2.553, p&lt;.009) associated with anxiety. Our results showed that increased feelings of anxiety were associated with an increase in lateral anticipatory postural adjustment, lateral neck movement, toe‐out angle, transverse range of motion in the back, turn angles, and number of steps in a turn. Anxiety was also associated with decreased neck rotation, asymmetries in mid‐swing elevation, step variability, and sagittal range of motion in the back. Our results indicate that as feelings of anxiety increase in intensity, subjects present with a more narrow base of support, which may cause the increase in lateral movements during gait. Identifying gait patterns associated with anxiety mood disorders may lead to improved identification of individuals that may benefit from preventative and/or early intervention care plans. Future research should focus on whether increased anxiety is associated with a greater input from higher brain areas that overpower the rhythmic neural output of learned central pattern generators of gait. Additionally, caution should be used to ensure that multiple diagnoses are considered in the presentation of distinct characteristics of gait patterns.

The effects of stereotype threat on older adults' walking performance as a function of task difficulty and resource evaluations.

Stereotype threat occurs when people are concerned about confirming a negative stereotype about their social group, and this often leads people to underperform within the threatened domain. Although this is well-documented, the majority of prior studies examining stereotype threat in older adults have focused on cognitive outcomes and comparatively less research has focused on how stereotype threat affects physical outcomes. In this study, we examined whether negative age-based evaluations invoke stereotype threat and adversely affect older adults' gait, and whether this depends upon the difficulty of the gait task and upon participants' evaluations of their own resources to cope with the demands of the gait task. To test this, we recruited 163 healthy, community-dwelling older adults and asked them to complete either an "easy" gait task (i.e., walking at their own comfortable pace) or a "difficult" gait task (i.e., walking within a 15 cm narrow base of support) along a 24' temporospatial-measuring walkway. This was done in either the presence or absence of a negative age-based evaluation. Results showed that the adverse effects of stereotype threat (i.e., walking slower, with relatively more variability in speed, and with more step errors) were generally limited to participants completing the difficult gait task who were not confident that they had sufficient resources to cope with the demands of the task. Thus, stereotype threat can impair older adults' physical performance, but the magnitude of this effect depends upon the task's objective difficulty and on participants' subjective evaluations of their own resources. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

THE EFFECTS OF AGE-BASED EVALUATIONS ON OLDER ADULTS’ GAIT VARIABILITY

Older adults are stereotyped as being slow, weak, and frail. In this study we examined how these stereotypes about age-related physical decline affect older adults’ walking performance. Healthy, community-dwelling older adults were asked to walk at their own comfortable pace along a 24’ temporospatial-measuring walkway 10 times. For some participants this was done with a normal-base of support (i.e., usual gait). However, for other participants this was done with a narrow-base of support (i.e., walking within a path of 15 cm outlined by tape). Walking tasks were done either in the presence or absence of a negative age-based evaluation. Results showed that the negative age-based evaluations were associated with greater stride-to-stride variability, particularly for participants who felt less confident in their abilities. Given that gait variability is a predictor of falling, this raises the possibility that negative age-based evaluations can produce concerns that are an intrinsic risk factor for falls.

Contribution of hip abductor-adductor muscles on static and dynamic balance of community-dwelling older adults.

The previous studies have investigated causes of and risk factors for falls and impairment of functional capability in older adults. However, the biomechanical factors involved in functional performance and postural control, and the contribution of hip muscles, are still unknown. The aim of the present study was to verify the association between the muscle function of hip abductors and adductors and static and dynamic balance, in a narrow base of support, in community-dwelling older adults. Eighty-one older adults, including both women and men, were evaluated. Tandem gait and single-leg stance were used to assess static and dynamic balance, and an isokinetic dynamometer was used to analyze muscle function (peak torque and rate of torque development according to body weight). Data were analyzed by a multivariate linear regression test without adjustment and with adjustment using two models: adjustment I (sex) and adjustment II (age). There was a statistically significant association between peak torque of abductor in single-leg stance and tandem gait speed. The PT of hip adductors contributed to static balance performance, in a narrow base of support from the unadjusted data and from the adjusted data by sex. The findings of the present study are relevant, because if deficits in balance and functionality in older adults can be linked to a decline in maximum muscle strength of hip abductors, this parameter can be treated to maintain independence in older adults for as long as possible.

Exergaming in a Moving Virtual World to Train Vestibular Functions and Gait; a Proof-of-Concept-Study With Older Adults.

Background: The use of Exergames designed to improve physical and cognitive functioning is relatively new in rehabilitation. Exergaming allows the training of skills, the handling of tools, and procedures; however, often, the potential of these aspects are not assessed before they are adopted in clinical settings. This study aimed at exploring the effects of exergaming on vestibular functions and gait in healthy community dwelling older adults using a proof-of-concept study design registered under ClinicalTrials.gov NCT03160352.Methods: A pre-test-post-test one-group study design comprising 10 older adults (mean age of 73.5 ± 7.6 years, four males) investigated the feasibility of eight exergaming training sessions (for 160 min) and the effects on dynamic visual acuity (DVA), functional gait assessment (FGA), and extended timed get-up-and-go (ETGUG). The simulator sickness questionnaire (SSQ) and the game scores were evaluated for the feasibility of the intervention. Wilcoxon test and Cohen’s d (d) were chosen to test for differences and for effect size estimation.Results: Exergaming led to a significantly improved DVA (z = −2.50, p = 0.01, d = 1.35) with improvements in 9 out of 10 participants. In addition, the FGA significantly improved with a large effect size (z = −2.25, p = 0.02, d = 1.17). Specifically, component tasks such as walking with horizontal head turns (p = 0.03), gait with a narrow base of support (p = 0.03), ambulating backward (p = 0.05) significantly improved. The ETGUG component task Gait initiation significantly improved (p = 0.04). No change was found in gait speed and SSQ. The game scores of the participants improved continuously during the course of the intervention for every game.Discussion: This proof-of-concept study suggests that the use of exergaming that requires active stepping movements and that contains moving game projection is feasible and facilitates gaze stability during head movements in healthy community dwelling older adults. Aspects of functional gait and gait initiation also improved. Future research aimed at testing this exergaming intervention in patients suffering from vestibular impairments is warranted.

Decomposition of leg movements during overground walking in individuals with traumatic brain injury

ABSTRACTObjective: Walking requires precise coordination of bilateral lower extremity motions at all joints. This ability can be affected by traumatic brain injury (TBI). The study investigated inter-joint coordination of lower extremities during overground walking after TBI.Methods: Ten individuals with post-injury ataxia, postural stability and gait abnormalities, as well as 10 sex- and age-matched control subjects were involved in the study. Participants walked at self-selected speed in three experimental conditions: normal walking without any additional task; walking with a narrow base of support, and walking while holding a cup full of water. Inter-joint coordination was analysed as the percentage of gait cycle during which the leg movement was decomposed with 0% indicating simultaneous motion of the two joints (i.e. hip-knee, knee-ankle, and hip-ankle) through the entire gait cycle or 100% indicating motion of only one joint. Decomposition was calculated for each pair of joints and for the left and right leg separately.Results: Participants with TBI showed greater decomposition indices and poorer inter-joint coordination respectively than control individuals for all joint pairs (p < 0.01). Walking with the narrower base of support or with a cup, increased movement decomposition in the TBI group, but not in the control group.Conclusion: The results revealed post-injury gait impairment that manifests as decomposition of multi-joint motions of the lower extremities during overground walking.

The Functional Gait Assessment in People with Multiple Sclerosis: Validity and Sensitivity to Change.

Assessments of balance and walking are often performed in rehabilitation of people with multiple sclerosis (MS). The Functional Gait Assessment (FGA) is a test of walking balance including challenging items such as walking with a narrow base of support, with eyes closed, and backward. The aim was to investigate the validity (concurrent, discriminant, and known-groups) and sensitivity to change of the modified FGA in ambulatory individuals with MS. A convenience sample of 87 individuals with MS was included (mean age, 54 years; 79% women). Concurrent and discriminant validity was investigated using tests of dynamic balance and the Multiple Sclerosis Walking Scale and Multiple Sclerosis Impact Scale (MSIS). Known-groups validity was investigated with self-reported number of falls and use of walking devices. Sensitivity to change was investigated with data from a group balance training study. The median FGA score was 15 (range, 1-26). Concurrent validity with tests of dynamic balance was moderate to strong, with the Timed Up and Go test having the highest correlation coefficient (rho = -0.74). Discriminant validity was shown with a low correlation coefficient with the MSIS psychological subscale (rho = 0.14). The FGA scores differed significantly for users of walking devices versus nonusers but not for reported falls. Sensitivity to change was moderate to low. The FGA is a valid measure of balance during walking in people with MS, but further investigation is required for the ability to detect people at risk for falls.

Bracing the trunk and neck in young adults leads to a more aged-like gait

Older individuals typically walk at slower speeds, with shorter step lengths, greater step widths and spend a larger proportion of the gait cycle in double stance. Changes in neck and trunk mobility may underlie some of the changes in walking seen with increasing age. Consequently, this study was designed to assess whether externally increasing trunk/neck stiffness in young adults leads to similar changes in gait pattern observed with aging. Twelve young adults (20–29 years), sixteen old adults (60–69 years) and fifteen older adults (70–79 years) walked across a 20′ pressure sensitive GAITRite© instrumented walkway at their preferred speed. The young adults also walked under three bracing conditions: (1) Neck braced, (2) Trunk braced, and (3) Neck and Trunk braced. The results revealed that the old and older age groups walked significantly slower, with a shorter step length and with a narrower base of support (p’s<0.05) compared to the young adults. In young adults, combined neck and trunk bracing led to reduced walking speed, shorter step length, wider base of support and a larger proportion of the gait cycle spent in double stance (p’s<0.05). The walking speed and step length of older adults remained less than fully braced young adults (p’s<0.05). Overall these results indicate that artificially stiffening the trunk and neck of young individuals leads to systematic gait changes similar to aging. Consequently, age-related changes in mobility of the neck and torso may in part contribute to the decrements in walking seen for older adults.

Validation of the Korean Functional Gait Assessment in Patients With Stroke

Background: The Functional Gait Assessment (FGA) was developed to measure of gait-related activities. The FGA was translated in Korean but only a few psychometric characteristics had been studied. Objects: The purpose of this study was to evaluate the validity and reliability of the Korean version of FGA scale using Rasch analysis. Methods: The study included 120 patients with stroke (age range=30~83 years; meanstandard deviation=). The FGA and Berg Balance Scale were performed, and were analysed for dimensionality of the scale, item difficulty, scale reliability and separation, and item-person map using Rasch analysis. Results: The 4 rating scale categories of FGA were satisfied with optimal rating scale criteria. The most items of the FGA showed sound item psychometric properties except 2 items ('gait with the horizontal head turns', and 'gait with narrow base of support'), and the 2 misfit items were excluded for all further analyses. The 8 items were arranged in order of difficulty. The most difficult item was 'gait with eyes closed', the middle difficult item was 'gait level surface', and the easiest item was 'gait with vertical head turns.' A person separation reliability was .93 and the person separation index was 3.57. Conclusion: This study suggests that the 8-item Korean FGA are valid measure of assess the gait-related balance performance, and to set the goal of rehabilitation plan in patient with stroke.

The quality of turning in Parkinson's disease: a compensatory strategy to prevent postural instability?

BackgroundThe ability to turn while walking is essential for daily living activities. Turning is slower and more steps are required to complete a turn in people with Parkinson’s disease (PD) compared to control subjects but it is unclear whether this altered strategy is pathological or compensatory. The aim of our study is to characterize the dynamics of postural stability during continuous series of turns while walking at various speeds in subjects with PD compared to control subjects. We hypothesize that people with PD slow their turns to compensate for impaired postural stability.MethodMotion analysis was used to compare gait kinematics between 12 subjects with PD in their ON state and 19 control subjects while walking continuously on a route composed of short, straight paths interspersed with eleven right and left turns between 30 and 180°. We asked subjects to perform the route at three different speeds: preferred, faster, and slower. Features describing gait spatio-temporal parameters and turning characteristics were extracted from marker trajectories. In addition, to quantify dynamic stability during turns we calculated the distance between the lateral edge of the base of support and the body center of mass, as well as the extrapolated body center of mass.ResultsSubjects with PD had slower turns and did not widen the distance between their feet for turning, compared to control subjects. Subjects with PD tended to cut short their turns compared to control subjects, resulting in a shorter walking path. Dynamic stability was smaller in the PD, compared to the healthy group, particularly for fast turning angles of 90°.ConclusionsThe slower turning speeds and larger turning angles in people with PD might reflect a compensatory strategy to prevent dynamic postural instability given their narrow base of support.

Coordination of muscle torques stabilizes upright standing posture: an UCM analysis.

The control of upright stance is commonly explained on the basis of the single inverted pendulum model (ankle strategy) or the double inverted pendulum model (combination of ankle and hip strategy). Kinematic analysis using the uncontrolled manifold (UCM) approach suggests, however, that stability in upright standing results from coordinated movement of multiple joints. This is based on evidence that postural sway induces more variance in joint configurations that leave the body position in space invariant than in joint configurations that move the body in space. But does this UCM structure of kinematic variance truly reflect coordination at the level of the neural control strategy or could it result from passive biomechanical factors? To address this question, we applied the UCM approach at the level of muscle torques rather than joint angles. Participants stood on the floor or on a narrow base of support. We estimated torques at the ankle, knee, and hip joints using a model of the body dynamics. We then partitioned the joint torques into contributions from net, motion-dependent, gravitational, and generalized muscle torques. A UCM analysis of the structure of variance of the muscle torque revealed that postural sway induced substantially more variance in directions in muscle torque space that leave the Center of Mass (COM) force invariant than in directions that affect the force acting on the COM. This difference decreased when we decorrelated the muscle torque data by randomizing across time. Our findings show that the UCM structure of variance exists at the level of muscle torques and is thus not merely a by-product of biomechanical coupling. Because muscle torques reflect neural control signals more directly than joint angles do, our results suggest that the control strategy for upright stance involves the task-specific coordination of multiple degrees of freedom.

The Functional Gait Assessment in Older Adults: Validation Through Rasch Modeling.

The Functional Gait Assessment (FGA), a measure of walking balance ability, was developed to eliminate the ceiling effect observed in the Dynamic Gait Index (DGI). Three presumably more difficult tasks were added and 1 easier task was removed from the original 8 DGI tasks. The effects of these modifications on item hierarchy have not previously been analyzed. The purpose of this study was to determine: (1) the ordering of the 10 FGA tasks and the extent to which they map along a clinically logical difficulty continuum, (2) whether the spread of tasks is sufficient to measure patients of varying functional ability levels without a ceiling effect, (3) where the 3 added tasks locate along the task difficulty continuum, and (4) the psychometric properties of the individual FGA tasks. A retrospective chart review was conducted. Functional Gait Assessment scores from 179 older adults referred for physical therapy for balance retraining were analyzed by Rasch modeling. The FGA task hierarchy met clinical expectations, with the exception of the "walking on level" task, which locates in the middle of the difficulty continuum. There was no ceiling effect. Two of the 3 added tasks were the most difficult FGA tasks. Performance on the most difficult task ("gait with narrow base of support") demonstrated greater variability than predicted by the Rasch model. The sample was limited to older adults who were community dwelling and independently ambulating. Findings cannot be generalized to other patient groups. The revised scoring criteria of the FGA may have affected item hierarchy. The results suggest that the FGA is a measure of walking balance ability in older adults that is clinically appropriate and has construct validity. Administration of the FGA may be modified further to improve administration efficiency.

Anticipatory and compensatory postural adjustments in conditions of body asymmetry induced by holding an object.

The effect of body asymmetry on anticipatory and compensatory postural adjustments was studied. Ten healthy subjects stood on the force platform and held an object in one hand which induced body asymmetry. Subjects were exposed to external perturbations applied to their shoulders while standing with either normal or narrow base of support. Bilateral electromyographic activity (EMG) of dorsal and ventral trunk and leg muscles and center-of-pressure displacements were recorded. Data was analyzed within the intervals typical for anticipatory (APA) and compensatory postural adjustments. Integrals of EMG activity and co-contraction and reciprocal activation of muscles were calculated and analyzed. Reciprocal activation of muscles on the target side and co-contraction of muscles on the contralateral side were seen when standing in asymmetrical stance and being subjected to external perturbations. Decreased magnitudes of co-contraction and reciprocal activation of muscles were seen in the APA phase while standing asymmetrically with narrow base of support. The findings highlight the importance of investigating the role of body asymmetry in maintaining control of vertical posture. The outcome of the study provides a foundation for future studies focusing on improvement in postural control in individuals with body asymmetry due to unilateral weakness.

Effects Of Resistance Training With Elastic Bands At Different Levels Of Intensity In Older Adults

Resistance training using weights is a good method for increasing the functional fitness of older adults, but less is known about the efficiency of non-traditional devices in this population. PURPOSE: To analyze the effects on performance of a short-term resistance training program with elastic bands (EB) at different intensities in older adults. METHODS: 105 older adults (69.90 ± 5.47 yr) took part in two familiarization sessions where they were instructed on the technique of EB exercises and use of the OMNI-RES for EB to evaluate perceived exertion. A total of 15 (15group (G), n=26), 10 (10G, n= 28) or 6 (6G, n= 28) repetitions were performed for each set at an intensity of 6-7 on the OMNI-RES for the first 3 wk and 8-9 the next 5 wk. Recovery times between sets were: 60, 90 and 120 sec for the 15G, 10G, and 6G, respectively. Two sec were allowed for each phase of the movements. The following exercises were performed for 2 sessions per wk: vertical and inclined rowing, elbow flexion, squat with wide and narrow base of support, and lunge. A control group (CG, n=23) continued normal activities without performing any new physical training. Dependent variables measured pre/post were: isometric maximum strength (IMS) for vertical rowing, squat and back extension; and functional fitness with the Senior Fitness Test (SFT). RESULTS: After averaging the results for all SFT assessments, the exercise groups improved significantly (p<0.05) compared to the CG, but there were not differences between the exercise groups (+25.66% 15G, +29.18% 10G, and +28.07% 6RG). The CG had a significant (p<0.05) decrease of 6.75% for the SFT. Increases (p<0.05) in IMS were also similar between exercise groups (15G +32.99%, 10G +30.91%, 6G +32.91%) while the CG decreased 5.04%. CONCLUSION: EB are an effective tool for improving performance and adaptations are similar between exercise intensities in short-term programs. Further research is needed to evaluate the effects of longer programs of different intensities.

Alteration of the foot center of pressure trajectory by an unstable shoe design.

BackgroundUnstable sole designs have been used as functional or therapeutic tools for improving body stability during locomotion. It has been suggested that the narrow base of support under the feet generate perturbations that challenge the instability of different joints during motion, thereby forcing the body to modify its movement in order to maintain a stable gait. The purpose of the present study was to explore the correlation between the stability of the footwear-device and the magnitude of perturbation conveyed during gait.MethodsVarious levels of dynamic instability were achieved using a novel foot-worn platform with two adjustable convex rubber elements attached to its sole. A total of 20 healthy male adults underwent direct in-shoe pressure measurements while walking with the footwear device. Foot center of pressure (COP) and stride to stride variability measures were extracted to examine the correlation between the magnitude of the instability and the imposed perturbations during gait.ResultsA counterintuitive but significant correlation was found between stride to stride variability and the instability of the biomechanical elements. Moreover, there was significant correlation between the instability of the elements and the perturbations found in the COP trajectory. The linear model describing this correlation was found to be statistically significant.ConclusionThere was significantly negative correlation between the level of instability induced by the shoe design and the amount of perturbations conveyed during gait. This suggests that the external perturbation must remain within a certain range limit. Exceeding this limit can negatively affect the treatment and probably lead to opposite results.