Postural Strategies Research Articles

Using functional movement tests to investigate the presence of sensorimotor impairment in amateur athletes following sport-related concussion: A prospective, longitudinal study

ObjectiveTo longitudinally investigate the presence of sensorimotor impairments in amateur athletes following sport-related concussion using two functional movement tests. DesignProspective, longitudinal study. SettingHuman movement analysis laboratory. ParticipantsAthletes who presented to a hospital emergency department and were diagnosed with sport-related concussion, and sex-, age-, and activity-matched non-concussed, control athletes. Concussed participants were assessed within one-week following sport-related concussion, upon clearance to return-to-sporting activity (RTA), and two weeks after RTA. Control participants were assessed at an initial time-point and approximately two and four weeks following their initial study assessment. Main outcomes measuresAt each laboratory assessment, participants completed two functional movement tests: the Star Excursion Balance Test to evaluate anterior reach distance (normalised for leg length) and fractal dimension (centre of pressure path complexity), and the Multiple Hop Test to evaluate corrective postural strategies and time-to-stabilisation. ResultsFifty concussed athletes and 50 control athletes completed the study. There were no significant differences at any study assessment between the concussion and control group on the Star Excursion Balance Test anterior reach distance or fractal dimension (centre of pressure path complexity). During the Multiple Hop Test, the concussion group used a significantly greater number of corrective postural strategies than the control group one-week following sport-related concussion and upon clearance to RTA, but not two weeks following RTA. ConclusionRecently concussed athletes made a greater number of corrective postural strategies than control participants during the Multiple Hop Test upon clearance to RTA but not two weeks after RTA. The Multiple Hop Test may offer a clinically useful tool for practitioners to examine the recovery of subtle sensorimotor impairments and related RTA readiness.

Postural control strategy after incomplete spinal cord injury: effect of sensory inputs on trunk\u2013leg movement coordination

BackgroundPostural control is affected after incomplete spinal cord injury (iSCI) due to sensory and motor impairments. Any alteration in the availability of sensory information can challenge postural stability in this population and may lead to a variety of adaptive movement coordination patterns. Hence, identifying the underlying impairments and changes to movement coordination patterns is necessary for effective rehabilitation post-iSCI. This study aims to compare the postural control strategy between iSCI and able-bodied populations by quantifying the trunk–leg movement coordination under conditions that affects sensory information.Methods13 individuals with iSCI and 14 aged-matched able-bodied individuals performed quiet standing on hard and foam surfaces with eyes open and closed. We used mean Magnitude-Squared Coherence between trunk–leg accelerations measured by accelerometers placed over the sacrum and tibia.ResultsWe observed a similar ankle strategy at lower frequencies (f ≤ 1.0 Hz) between populations. However, we observed a decreased ability post-iSCI in adapting inter-segment coordination changing from ankle strategy to ankle–hip strategy at higher frequencies (f > 1.0 Hz). Moreover, utilizing the ankle–hip strategy at higher frequencies was challenged when somatosensory input was distorted, whereas depriving visual information did not affect balance strategy.ConclusionTrunk–leg movement coordination assessment showed sensitivity, discriminatory ability, and excellent test–retest reliability to identify changes in balance control strategy post-iSCI and due to altered sensory inputs. Trunk–leg movement coordination assessment using wearable sensors can be used for objective outcome evaluation of rehabilitative interventions on postural control post-iSCI.

Postural control in top-level female volleyball players

BackgroundThe aim of this study was to compare the postural control of the Poland national women’s volleyball team players with a control group of non-training young women. It was hypothesized that volleyball players use a specific balance control strategy due to the high motor requirements of their team sport.MethodsStatic postural sway variables were measured in 31 athletes and 31 non-training women. Participants were standing on a force plate with eyes open, and their center of pressure signals were recorded for the 20s with the sampling rate of 20 Hz in the medial-lateral (ML) and anterior-posterior (AP) planes.ResultsIn both AP and ML planes, athletes had lower range and higher fractal dimension of the COP. They had also higher peak frequency than control group in the ML plane only. The remaining COP indices including variability, mean velocity and mean frequency did not display any intergroup differences.ConclusionIt can be assumed that due to the high motor requirements of their sport discipline Polish female volleyball players have developed a unique posture control. On the court they have to distribute their sensory resources optimally between balance control and actions resulting from the specifics of the volleyball game. There are no clearly defined criteria for optimal postural strategies for elite athletes, but they rather vary depending on a given sport. The results of our research confirm this claim.Trial registrationThe tests were previously approved by the Bioethical Commission of the Chamber of Physicians in Opole. (Resolution No. 151/13.12.2007). This study adheres to the CONSORT guidelines.

Advanced characterization of static postural control dysfunction in persons with multiple sclerosis and associated neural mechanisms

BackgroundMultiple sclerosis (MS) is an autoimmune-based chronic inflammatory disease characterized by the neurodegeneration of the central nervous system and produces postural dysfunction. Quiet or static standing is a complex task carried out through afferent sensory inputs and efferent postural corrective outputs. Currently the mechanisms underlying these outputs remain largely unknown. Research questionAssess the relationship between multi-dimensional measures of postural control and microstructural integrity of the cortical sensorimotor pathway (CSP) in persons with MS (PwMS) and neurotypical adults. MethodsPostural control performance was assessed by both overall and directional time-to-boundary measures across four manipulated sensory stance conditions (eyes open/closed; stance firm/foam) in twenty-nine neurotypical and twenty-seven PwMS. These postural outcomes were evaluated with mixed-model repeated measures analysis of variance across group (MS and control) and stance condition. Postural performance was also correlated with magnetic resonance imaging diffusion tensor-derived measures of microstructural integrity of the CSP. ResultsPwMS displayed significantly (p = 0.026) worse anterior-posterior postural control compared to their neurotypical counterparts across sensory testing conditions and poorer CSP microstructural integrity in comparison to neurotypical adults (p = 0.008). Additionally, PwMS displayed a significant association (2D (rho = -0.384, p = 0.048), AP (rho = -0.355, p = 0.035), and ML (rho = -0.365, p = 0.030) between integrity of the CSP and postural control performance during proprioceptive-based balance, such that those with worse cortical structure had poorer balance control. SignificanceThis is the first study to establish connections between the microstructural integrity of the CSP and multi-dimensional postural control performance. Results indicate that a reduction in the CSP microstructural integrity is associated with poorer postural control in PwMS. These outcomes identify neural underpinnings of postural control dysfunction in PwMS and provide new avenues for evaluating the efficacy of postural rehabilitation strategies in PwMS that express proprioceptive-based postural deficits.

Difference of static postural balance in patients with Parkinson's Disease and scans without evidencec of dopaminergic deficits

Differentiating scans without evidence of dopaminergic deficit (SWEDD) from Parkinson's disease (PD) is very important to avoid costly and inappropriate interventions. Little is known of postural balance strategy of SWEDD patients. The purpose of this study was investigate difference of static postural balance between SWEDD and PD patients. Eleven patients with SWEDD, 11 patients with PD and normal subjects were instructed to quietly stand on a force plate in a comfortable self selected stance width. Center of pressure (COP) was measured for quantitative evaluation during static standing. As outcome measure, mean distance, mean velocity, 95% confidence ellipse area, mean frequency, peak frequency and peak power were derived from the COP time series in overall, anterio-posterior (AP) and medio-lateral (ML) directions. ANOVA and post hoc test were evaluated for comparison between SWEDD patients and PD patients. SWEDD patients presented a smaller postural sway size and a more frequent postural sway manly in ML direction (p< 0.05). In contrast, there was no significant differences in mean velocity and peak power (p>0.05). There were no significant difference between SWEDD patients and normal subjects (p>0.05). These results indicate that some COP-based outcome variables might be useful to distinguish SWEDD patients with PD patients. This study suggests that static postural balance test could aid clinicians in the identification of potential SWEDD.

Research on the Posture Control Method of Hexapod Robot for Rugged Terrain

This paper proposes a hexapod robot posture control method for rugged terrain to solve the problem of difficulty in realizing the posture control of a foot robot in rough terrain. The walking gait and original position of a six-legged robot is planned, and the Layer Identification of Tracking (LIT) strategy is developed to enable the robot to distinguish mild rugged terrain and severe rugged terrains automatically. The virtual suspension dynamic model is established. In mild rugged terrain, the posture maintenance strategy is adopted to keep the stability of the torso. In severe rugged terrain, the posture adjustment strategy is adopted to ensure the leg workspace and make it more widely adapt to the changing terrain, and a gravity center position adjustment method based on foot force distribution is designed to use foot force as feedback to control the position and attitude. The experiment of posture control in rough terrain and climbing experiment in the ladder terrain shows that the hexapod robot has good posture maintenance and posture adjustment effects when traversing complex terrain through the posture maintenance strategy and the posture adjustment strategy. Combined with the terrain identification method based on LIT, the hexapod robot can successfully climb the ladder terrain through the identification of the changing ladder terrain, and the movement of the posture adjustment process is stable.

COMPARISON OF STATIC POSTURAL BALANCE IN PATIENTS WITH SWEDDS AND PARKINSON’S DISEASE

Differentiating scans without evidence of dopaminergic deficits (SWEDDs) from Parkinson’s disease (PD) is very important to avoid costly and inappropriate interventions. The postural balance strategy patients with SWEDDs are not clear. This study investigates the difference in static postural balance between patients with SWEDDs and PD. Twenty-two patients (11 SWEDDs and 11 PD groups) and 11 control groups were instructed to quietly stand on a custom-made force platform. The outcome measures were, mean distance, 95% confidence ellipse area, mean velocity, mean frequency, peak frequency and peak power derived from the center of pressure (COP) data in overall, medio-lateral (ML) and anterio-posterior (AP) directions. As statistical analysis, ANOVA and post hoc tests were conducted for comparison of patients with SWEDDs and PD. SWEDDs patients presented a smaller postural sway size and a more frequent postural sway mainly in the ML direction ([Formula: see text]). On the contrary, there were no significant differences in mean velocity and peak power. Also, no significant differences existed between SWEDDs and normal subjects ([Formula: see text]). The results reflect that a few COP-based outcome variables might be useful to distinguish SWEDDs patients from PD patients. This study suggests that a static postural balance test can be used for clinical screening and identification of potential SWEDDs.

Centre of pressure versus centre of mass stabilization strategies: the tightrope balancing case.

This study proposes a generalization of the ankle and hip postural strategies to be applied to the large class of skills that share the same basic challenge of defeating the destabilizing effect of gravity on the basis of the same neuromotor control organization, adapted and specialized to a variable number of degrees of freedom, different body parts, different muscles and different sensory feedback channels. In all the cases, we can identify two crucial elements (the CoP, centre of pressure and the CoM, centre of mass) and the central point of the paper is that most balancing skills can be framed in the CoP–CoM interplay and can be modelled as a combination/alternation of two basic stabilization strategies: the standard well-investigated COPS (or CoP stabilization strategy, the default option), where the CoM is the controlled variable and the CoP is the control variable, and the less investigated COMS (or CoM stabilization strategy), where CoP and CoM must exchange their role because the range of motion of the CoP is strongly constrained by environmental conditions. The paper focuses on the tightrope balancing skill where sway control in the sagittal plane is modelled in terms of the COPS while the more challenging sway in the coronal plane is modelled in terms of the COMS, with the support of a suitable balance pole. Both stabilization strategies are implemented as state-space intermittent, delayed feedback controllers, independent of each other. Extensive simulations support the degree of plausibility, generality and robustness of the proposed approach.

Static pelvic posture is not related to dynamic pelvic tilt or competition level in dressage riders

ABSTRACT Static assessment and grouping of riders by competition level are prevalent in equestrian coaching practice and research. This study explored sagittal pelvic tilt in 35 competitive dressage riders to analyse the relationship between static and dynamic postures and assess the interaction of competition level. Riders were assessed using optical motion capture on a riding simulator at halt and in walk, trot, and left and right canter. Mean, minimum and maximum pelvic tilt, and range of motion (ROM) were measured as the pitch rotation of a rigid body formed by markers placed on the rider’s left/right anterior and posterior superior iliac spines and sacrum, averaged over six time-normalised strides. Three key results emerged: (1) there are correlations between the rider’s mean pelvic tilt in simulated walk, trot and canter, but not at halt; (2) mean pelvic tilt values are not significantly influenced by competition level (p = 0.233); and (3) the minimum and maximum pelvic tilt values illustrate individual strategies between gaits. Therefore, results from static assessment and grouping of riders by competition level should be interpreted with caution. Riders should be assessed as individuals, during dynamic riding-specific tasks, to understand their postural strategies.

A new postural stability-indicator to predict the level of fear of falling in Parkinson\u2019s disease patients

BackgroundFear of falling (FoF) is defined as a lasting concern about falling that causes a person to limit or even stop the daily activities that he/she is capable of. Seventy percent of Parkinson’s disease (PD) patients report activity limitations due to FoF. Timely identification of FoF is critical to prevent its additional adverse effects on the quality of life. Self-report questionnaires are commonly used to evaluate the FoF, which may be prone to human error.ObjectivesIn this study, we attempted to identify a new postural stability-indicator to objectively predict the intensity of FoF and its related behavior(s) in PD patients.MethodsThirty-eight PD patients participated in the study (mean age, 61.2 years), among whom 10 (26.32%) were identified with low FoF and the rest (73.68%) with high FoF, based on Falls Efficacy Scale-International (FES-I). We used a limit of stability task calibrated to each individual and investigated the postural strategies to predict the intensity of FoF. New parameters (FTRis; functional time ratio) were extracted based on the center of pressure presence pattern in different rectangular areas (i = 1, 2, and 3). The task was performed on two heights to investigate FoF-related behavior(s).ResultsFTR1/2 (the ratio between FTR1 and FTR2) was strongly correlated with the FES-I (r = − 0.63, p < 0.001), Pull test (r = − 0.65, p < 0.001), Timed Up and Go test (r = − 0.57, p < 0.001), and Berg Balance Scale (r = 0.62, p < 0.001). The model of FTR1/2 was identified as a best-fitting model to predicting the intensity of FoF in PD participants (sensitivity = 96.43%, specificity = 80%), using a threshold level of ≤ 2.83.ConclusionsUsing the proposed assessment technique, we can accurately predict the intensity of FoF in PD patients. Also, the FTR1/2 index can be potentially considered as a mechanical biomarker to sense the FoF-related postural instability in PD patients.

Sound Effects on Standing Postural Strategies in the Elderly via Frequency Analysis Approach

Sound and sound frequency could improve postural sway in the elderly. The power spectrum intervals of the center of pressure (COP) displacement are associated with different postural regulations, which could be revealed by frequency analysis. The aim of the study was to investigate the effects of sound on dual-tasking postural control and conduct frequency analysis to distinguish postural regulations in the elderly. Fifteen young and 15 older healthy participants were instructed to stand on a force platform and performed the Purdue Pegboard test while hearing 50 dB sounds with sound frequencies of 250 Hz, 1000 Hz, 4000 Hz, or no sound. The total excursion, velocity, sway area, and power spectrum of low-, medium-, and high-frequency bands of the COP displacement were calculated in the anterior–posterior and medial–lateral directions. The percentages of low-frequency and medium-frequency bands in both directions were significantly different between with and without sound conditions, but not affected by sound frequency. Older adults showed a smaller percentage of low-frequency, larger percentage of medium-frequency, larger total COP excursion, and faster velocity in the medial–lateral direction. The outcome of the study supports the frequency analysis approach in evaluating sound effects on postural strategies in dual-tasking and reveals older adults utilize vestibular regulation as the primary postural strategy when the dual-task required visual attention.

Fear Priming: A Method for Examining Postural Strategies Associated With Fear of Falling.

Fear of falling influences postural strategies used for balance, and is key in the maintenance of independent living and quality of life as adults age. However, there is a distinct need for methodology that aims to specifically address and prime fear under dynamic conditions, and to better determine the role of fear in movement preparation. This preliminary study investigated how fear priming influences fear of falling in young and older individuals, and assessed how changes in fear of falling map to movement behavior. Young (21.5 ± 1.7 years, n = 10) and older (58.1 ± 2.2 years) participants matched for height, weight, and sex were repeatedly exposed to four different and incrementally challenging laboratory-based slipping perturbations during a self-initiated, goal-directed step and reach task. Both younger and older cohorts showed similar heightened perceptions in fear of falling after fear priming, and changes in peak joint excursions including reduced ankle flexion, and increased lumbar flexion after fear priming. Age-related changes were only evident in total mediolateral center of mass displacement, with younger participants showing greater displacement after fear priming. Despite clear differences in preparatory muscle onsets relative to reach onset seen in older participants, muscle timings or co-contraction indices were not significantly different. Methods utilizing repeated exposure to varying increases of a slip-based postural challenge can successfully prime fear of falling in individuals, regardless of age.

Balance abilities of junior ice hockey players.

Postural control is required during various fast-paced and offensive ice hockey actions, and therefore seems to be an important component in ice hockey performance. Data were collected from two ice hockey teams with differing performance levels. The higher-performance team consisted of 26 players (with ages of 16.3±0.9 y, heights of 178.26±6.71 cm, and weights of 74.3±9.6 kg). The lower-performance team consisted of 19 players (with ages of 16.2±1.8 y, heights of 176.11±9.81 cm, and weights of 68.7±13.9 kg). Each participant performed six unilateral stances under static conditions on a balance pad placed on a force platform and five bilateral stances under dynamic conditions using a wobble board placed on the force platform. The higher-level players performed better in the unilateral static stance task in both the anterior-posterior direction and the medial-lateral direction (with a P value of P<0.001), and total velocity (P=0.001). The higher-level players also performed better in both the anterior-posterior and medial-lateral directions, and total velocity (with P value of P<0.001), in the bilateral dynamic stance task and therefore performed significantly better than the lower-level players. Hockey players who possess a highly developed postural control strategy have a superior ability to compensate for unexpected postural disturbances and collisions, and thus possess a strong competitive advantage. Therefore, testing the balance abilities of hockey players under static and dynamic conditions may be useful for evaluating their competitive performance levels.

The Effect of Eight Weeks of Training on Head and Neck Stability in Tsuki Punch after Neck Muscle Fatigue

Introduction : Muscular fatigue can interfere with the proper functioning of postural stability strategies, hence decreasing stability and increasing the risk of injuries in athletes. The aim of this study is to examine the effect of training on head and neck stability against Tsuki punch during the neck muscle fatigue in male athletes. Materials and Methods: 24 professional male karate athletes were selected and randomly divided into the experimental [n = 12, age: 20.92 ± 2.62 (y), weight: 71.00 ± 11.68 (kg), height: 1.77 ± 0.05 (m)] and control [n = 12, age: 22.08 ± 2.21 (y), weight: 72.15 ± 13.24 (kg), height: 1.78 ± 0.06 (m)] groups. The experimental group performed a training program for eight weeks, three times per week. Moreover, the angular displacement and acceleration of head and neck in Tsuki punch during muscular fatigue were measured by motion analysis system before and after the training protocol. Data were analyzed by paired t-test, independent t-test, and analysis of covariance (ANCOVA) at the significance level of 0.05. Results: There was a significant difference in angular displacement (Experimental: 2.95 ± 1.85, Control: 4.15 ± 2.15) and acceleration before (Experimental: 16.29 ± 9.62, Control: 70.17 ± 12.23) and after (Experimental: 24.69 ± 15.98, Control: 70.86 ± 14.92) hitting the punching bag. Conclusion: The outcome of this study showed that proprioception training can improve head and neck postural stability during muscular fatigue against external perturbation in Karate athletes. Therefore, these exercises can be used to reduce the effect of external perturbation on the head and neck of these athletes.

Feasibility of postural lung recruitment maneuver in children: a randomized, controlled study

BackgroundPulmonary atelectasis in anesthetized children is easily reverted by lung recruitment maneuvers. However, the high airways pressure reached during the maneuver could negatively affect hemodynamics. The aim of this study is to assess the effect and feasibility of a postural lung recruitment maneuver (P-RM); i.e., a new maneuver that opens up the atelectatic lung areas based on changing the child’s body position under constant ventilation with moderated driving pressure (12 cmH2O) and of positive end-expiratory pressure (PEEP, 10 cmH2O). Forty ASA I–II children, aged 6 months to 7 years, subjected to general anesthesia were studied. Patients were ventilated with volume control mode using standard settings with 5 cmH2O of PEEP. They were randomized into two groups: (1) control group (C group, n = 20)—ventilation was turned to pressure control ventilation using a fixed driving pressure of 12 cmH2O. PEEP was increased from 5 to 10 cmH2O during 3 min maintaining the supine position. (2) P-RM group (n = 20)—patients received the same increase in driving pressure and PEEP, but they were placed, respectively, in the left lateral position, in the right lateral position (90 s each), and back again into the supine position after 3 min. Then, ventilation returned to baseline settings in volume control mode. Lung ultrasound-derived aeration score and respiratory compliance were assessed before (T1) and after (T2) 10 cmH2O of PEEP was applied.ResultsAt baseline ventilation (T1), both groups showed similar aeration score (P-RM group 9.9 ± 1.9 vs C group 10.4 ± 1.9; p = 0.463) and respiratory compliance (P-RM group 15 ± 6 vs C group 14 ± 6 mL/cmH2O; p = 0.517). At T2, the aeration score decreased in the P-RM group (1.5 ± 1.6 vs 9.9 ± 2.1; p < 0.001), but remained without changes in the C group (9.9 ± 2.1; p = 0.221). Compliance was higher in the P-RM group (18 ± 6 mL/cmH2O) when compared with the C group (14 ± 5 mL/cmH2O; p = 0.001).ConclusionLung aeration and compliance improved only in the group in which a posture change strategy was applied.

Effect Of Bracing For Scoliosis In Improving Gait Mechanics

Patients with scoliosis demonstrate altered gait due to changes in global postural control strategies caused by pain and the spinal deformity. Bracing has been found to reduce pain and increase trunk support in adult degenerative scoliosis (ADS) patients.However, only anecdotal evidence of their efficacy is available in improving gait and posture control mechanics. PURPOSE: Investigate the impact of scoliosis bracing on lower extremity kinematics and effectiveness in gait rehabilitation. METHODS: 15 patients with ADS (cobb angle >25°; age:73.9±2.9yr; weight:66.6±16.2kg) were recruited using the adult deformity SRS-Schwab system. Oswestry Disability Index (ODI) scores were recorded and patients performed 3m timed up & go, 6 minute walk tests and over-ground 10m walk trials at a self-selected speed at initial evaluation (pre), 45min post fitting (post45) with Peak™ scoliosis brace and after 8 weeks of bracing (post8w). Gait variables were calculated for 5 walking trials and compared between the 3 time points (pre, post45 and post8w) using RM-MANOVA (p< .05). RESULTS: Patients walked faster on 3m timed test (pre: 12.5s; post8w: 10.0s) and covered greater distances in the 6 min walk test (p= .01; 61.2m). For kinematic variables, significant differences were observed for swing time of left leg (p =.013; pre:0.40s; post45:0.42s; post8w:0.39s), step length on right (p=.019; pre:0.52m; post45:0.57m; post8w:0.56m), right ankle peak dorsiflexion (p =.049; pre:8.7°; post45:7.9°; post8w:11.7°), both knee peak flexion and extension angles (p <.001- .048), and right hip (p =.002; pre:37.2°; post45:39.2°; post8w:31.6°) and knee ROM (p =.018; pre:29.8° ; post45:31.6°; post8w:37.7°). ODI pain scores (p=.06) showed tendency for statistical significance. CONCLUSIONS: Patients with scoliosis demonstrated few immediate and long-term benefits for improving pain and altered gait mechanics. Faster walking speeds, greater walking distances, longer step lengths and greater ROM as observed are indicators of improved gait and dynamic balance. Bracing has immediate effects on improving ambulation and for any neuromuscular adaptation, brace might need to be worn for at least 8 weeks.

Control of landing under conditions of height-induced threat.

Landing involves a tuned anticipatory control to allow for soft and safe contact with the ground. Fearful situations are known to affect postural control strategies during standing, but it is still unclear how fear interferes with the control of a voluntary dynamic task requiring coordination between posture and movement. Ground reaction forces, limb movements, physiological arousal, and perceived levels of confidence and fear of falling were recorded when hopping off a box to a platform situated 0.8m above ground and 3.2m above ground. Height induced a perceived threat as arousal was augmented by the elevated surface for all subjects. Threat induced by height modifies the way participants land, leading to a stiffer landing, as evidenced by an increased loading rate at touchdown during high threat conditions. Greater psychological and physiological changes are associated with greater changes in the control of landing: individuals that are less confident/more fearful appear to compensate for this stiffer landing, by slowing down their landing. Threatening conditions induces a harder contact to the ground, but the strategy is dependent of the level of confidence/fear. Less confident/more fearful participants are more focused on coping strategy and adopt a more cautious behaviour.

POSTURAL BALANCE AND QUALITY OF LIFE OF 70-74 YEARS OLD WOMEN

The aim was to study age-related quality of life (QoL) and postural balance (OPB) in 70-74 years old women. Methods. A total of 700 women aged 65-74 years were examined. The first (reference group) age group (AG) included women aged 65-69 years (n = 437), and the second AG (study group) included women 70-74 years old (n = 263). Physical Component Summary (PCS) and Mental Component Summary (MCS) associated with health were assessed using the questionnaire SF-36v1. To evaluate CPB, the Sensory Organization Test (SOT) and the Motor Control Test (MCT) were performed using the computerized dynamic posturography Smart Equitest Balance Manager. Results. It was found that MCS indicators in women aged 70-74 were higher than in women 65-69 years old (p = 0.008), and PCS indicators did not differ between groups (p &gt; 0.1) The study of the peculiarities of the CPB showed that in women 70-74 years old, compared with the previous age group, the ratio for sensory analysis - Somatosensory increases (p = 0.006). Thus, the values of the computerized dynamic posturography according to SOT and MCT data indicate the state of CPB in women 70-74 years old at the level of 65-69 year old women. Conclusions. The quality of life associated with health in 70-74 years old women concerning the Physical Component Summary does not differ from that of the 65-69 years old women, however, there is an increase in the Mental Component Summary after 69 years. Women 70-74 years old don't have changes in the Equilibrium Score, Postural Strategy Score, sensory organization of postural control, as well as an increase in the time of coordinated motor reactions. However, they experience an increase in the ratio for sensory analysis - Somatosensory.

Os efeitos do método Pilates sobre o equilíbrio e as estratégias posturais em idosos

Objetivo: Analisar o impacto da prática do método Pilates sobre o equilíbrio e as estratégias posturais em idosos. Materiais e Métodos: Trata-se de um estudo de intervenção, no qual foram incluídos 14 idosos, cujo equilíbrio foi avaliado por meio da Posturografia Dinâmica Computadorizada, incluindo os testes de organização sensorial (TOS), divididos em seis condições, e analisadas as estratégias posturais (condição I à VI) e os sistemas neurais responsáveis pelo equilíbrio (visual, vestibular e somatossensorial). Os idosos praticaram os exercícios do método Pilates ao longo de 8 semanas, sendo duas vezes por semana, por aproximadamente 50 a 60 minutos. Resultados: Houve um aumento do uso das estratégias posturais de tornozelo nas condições: II (p=0,04) e VI (p=0,01), pós-intervenção. Contudo, as condições sensoriais dos TOS e os sistemas neurais responsáveis pelo equilíbrio não modificaram-se pós-intervenção. Conclusões: A prática do método Pilates contribuiu para a melhora do uso das estratégias posturais em idosos, podendo, consequentemente, reduzir o risco de queda nos mesmos. No entanto, não houve diferença significativa sobre os TOS e os sistemas neurais, e, acredita-se que há a necessidade de uma prática mais prolongada do método para a obtenção de efeitos mas significativos sobre esses achados.

Robust transition control of underactuated two-wheeled self-balancing vehicle with semi-online dynamic trajectory planning

In order to increase the mobility and dynamic agility of a two-wheeled self-balancing vehicle, a dynamic posture control strategy for the initial state transition is proposed in terms of a well-planned nonlinear reference trajectory. The dynamic trajectory planning for the underactuatedmobile inverted pendulum is conducted by solving a two-point boundary value problem with the constraint equation of internal dynamics. The restriction of the offline trajectories for real-time applications is relaxed by establishing a semi-online planning method by assuming velocity-controlled missions. For the transition tasks requiring high maneuver motions including quick start and stop and quick speed change, the proposed control scheme is profitable to stabilize the initial transient motion and get over the performance limit of the conventional feedback-only control with typical step reference inputs. As a result, it enables to achieve consistent state transition to the target velocity and requires just minimal control efforts.