Postural Balance Control Research Articles

Effect of Car Driving on Postural Balance Control

Effect of Car Driving on Postural Balance Control

Physical active lifestyle promotes static and dynamic balance performance in young and older adults.

Although regular physical activity exposure leads to positive postural balance control (PBC) adaptations, few studies investigated its effects, or the one of inactivity, on PBC in populations of different age groups. Thus, this study investigated the impact of a physically active lifestyle on static and dynamic PBC in young and older adults. Thirty-five young physically active subjects (YA), 20 young sedentary subjects (YS), 16 physically active older adults (OA), and 15 sedentary older adults (OS) underwent a static and a dynamic PBC assessment. A force platform and an instrumented proprioceptive board were employed to measure the center of pressure (COP) trajectory and the anteroposterior oscillations, respectively. In static conditions, no significant differences were detected among groups considering the overall postural balance performance represented by the area of confidence ellipse values. Conversely, the YA highlighted a higher efficiency (i.e., lower sway path mean velocity) in PBC maintenance compared to the other groups (YA vs OA: p = 0.0057, Cohen’s d = 0.94; YA vs OS p = 0.043, d = 1.07; YA vs YS p = 0.08, d = 0.67). OS exhibited an overall worse performance in dynamic conditions than YA and YS. Surprisingly, no differences were found between YS and OA for all the static and dynamic parameters considered. In conclusion, our results suggest that a physically active lifestyle may promote static and dynamic balance performance in young and older adults, thus with potentially positive effects on the age-related decline of postural balance performance. Dynamic PBC assessment seems more sensitive in detecting differences between groups than the static evaluation.

Relationship between Cervicocephalic Kinesthetic Sensibility Measured during Dynamic Unpredictable Head Movements and Eye Movement Control or Postural Balance in Neck Pain Patients.

Cervical afferent input is believed to affect postural balance and oculomotor control in neck pain patients, but its relationship to cervicocephalic kinesthesia, describing movement sense, has not yet been studied. The aim of this study was to analyze the relationship of two aspects of cervicocephalic kinesthesia to postural balance and oculomotor control in neck torsion positions. Forty-three idiopathic neck pain patients referred from orthopedic outpatient clinics and forty-two asymptomatic controls were enrolled in the study. A force plate was used to measure center-of-pressure movements during parallel stances under neutral and neck torsion maneuvers. Video-oculography was used to assess eye movements during smooth pursuit neck torsion test (SPNTT), while kinesthetic awareness was measured using the Butterfly test and head-to-neutral relocation test. Multiple regression was used to describe relationships between tests. Body sway in the anterior–posterior direction was related to Butterfly parameters but less to the head-to-neutral test. A medium relationship between Butterfly parameters and gain during SPNTT, with less SPNT-difference, was observed, but not for the head-to-neutral test. It can be concluded that specific aspect of neck kinesthetic functions (i.e., movement sense) importantly contributes towards oculomotor and balance control, which is more evident under neck torsion positions in neck pain patients, but is less pronounced in asymptomatic individuals.

Association Between Sleep Parameters and Postural Control: A Literature Review

Background and Objective The purpose of the review was to explore the association between sleep parameters and postural control.Methods The PubMed, Science Direct, and EBSCO were searched using the keywords ‘sleep’ including either sleep quality, sleep deprivation, poor sleep quality; and ‘postural control’ including either dynamic balance, static balance, postural balance, and balance control. Related studies published till December 2017 were selected.Results Acute sleep deprivation resulted in an impairment in postural control. Chronic sleep deprivation and postural control were also found to be related in a similar way to that of total sleep deprivation, thus affecting postural control negatively. Time of day was found to influence the postural control such that the postural control was better in the morning than in the latter part of the day. A study of the impact of aging on the effects of sleep deprivation on postural control revealed that loss of sleep had a more disturbing effect on postural control in the olderadult group than in younger participants, thus indicating a high risk of fall among the elderly.Conclusions Despite various limitations and methodological differences, this review has identified a negative influence on postural control due to impaired sleep in a wide range of populations, indicating the need for a more focused approach to sleep when assessing and measuring postural control.

Особенности постуральных нарушений и связей с системой комплемента крови при синдроме падений у пожилых

Background: Natural and premature aging is accompanied by postural disorders, which are aggravated in patients with ophthalmic pathology and lead to the occurrence of the falls syndrome, but remain insufficiently studied in patients with angle-closure glaucoma with a change in the blood compliment system. The aim of the study:To study postural disorders and connections with the blood compliment system with angle-closure glaucoma. Materials and methods: The study was conducted in 62 elderly patients with falls syndrome and angle-closure glaucoma (main group) and 49 60-74-year-old patients with no falls and angle-closure glaucoma and other eye diseases. Postural disorders were studied using the Sensori Organization Test on a computer stabilometric complex in 6 functional tests (COND 1-6) and with an assessment of the somatosensory system, visual analyzer and the use of visual information in ensuring postural balance. The components of the blood compliment system were examined by enzyme immunoassay. The study of correlations was checked by the correlation method using the program "Statistica 10.0". Results: Negative changes in postural balance in the elderly with falls syndrome and angle-closure glaucoma were detected in all 6 functional tests, but the most pronounced deterioration was noted in functional tests COND 2, COND 4 and COND 6. There was a decrease in the participation of the visual analyzer, somatosensory system and preference for using visual information in control of postural balance. Postural disturbances in patients with falls syndrome and angle-closure glaucoma are more associated with C3 C3a and C5a components of the blood compliment system and especially in functional tests COND 4, COND 6.

The effect of proprioceptive training in the STAR Excursion Balance Test (SEBT)

Abstract Introduction. To control the movement, the brain must process proprioceptive information provided by mechanoreceptors. The role of proprioception in carrying out daily activities and physical exercises, was presented, using the SEBT technique and the proprioceptive mechanisms that represent the base of dynamic postural control. Objective. The aim was to highlight the effects of proprioceptive training on lower limb balance in subjects with lower limb injuries but also in healthy subjects, and to evaluate the effectiveness of proprioceptive programs based on postural instability to reduce knee sprains by developing proprioceptive control. These findings indicate the improvement of proprioceptive control which may be a key factor in reducing knee sprain. Working hypothesis. Applying a kinetic intervention protocol, consisting of static proprioceptive exercises, stimulates the body to maintain balance in situations of imbalance and increases the stability of the knee joint in Ministry of National Defense workers with a history of sprained knee or predisposition to injury. Methods. The research was performed on 30 subjects, male and female, employees of the Ministry of National Defense, distributed in two experimental groups: G1 and G2. Results. The results demonstrate the effectiveness of the applied program, both for therapeutic and prophylactic purposes, in increasing postural balance and proprioceptive control. Conclusions. Knee sprain is a trauma that occurs frequently among athletes. Like athletes, the Ministry of National Defense employees represent a population at high risk of injury or recurrence.

Impact of Gender, Change of Base of Support, and Visual Deprivation on Postural Balance Control in Young, Healthy Subjects

Background: Vision, vestibular sense, proprioception and muscle strength are required to maintain balance. However, gender could also play a crucial role in postural sway. Objectives: This study was used to examine (i) the impact of gender, surface type, and vision on postural sway; (ii) the effects of gender and vision on the limb symmetry of postural sway; and (iii) to understand the effects of gender, stance, surface type and vision on the alterations of dynamic postural sway alterations. Methods: This was a cross-sectional study in which young, healthy men (n = 15) and women (n = 12) underwent a balance control assessment using a force plate (SATEL, 40 Hz). Postural stances were evaluated in different conditions: Opened eyes (EO) and closed eyes (EC), on different surface foam vs. firm, a dominant leg stance (DL) vs. a non-dominant leg stance (NDL), and a mediolateral stance (ML) vs. an anteroposterior stance (AP). The mediolateral sway (ML sway), anteroposterior sway (AP sway), and sway area were calculated from the centre of pressure displacements. Results: ML sway, AP sway and sway area increased when eyes were closed (P < 0.000). Foam surface perturbs balance control more than firm surface under EO and EC conditions for both genders, as observed in the AP sway curve (P < 0.000). A functional symmetry exists between the DL and NDL for all sway parameters: The ML sway, AP sway, and sway area (P = 0.720; P = 0.292; P = 0.954). The AP stance is more stable for the ML sway than the ML stance for both genders (P < 0.001). For the AP sway, the ML stance is more stable than the AP sway AP direction stance for both genders (P < 0.001). Women were significantly more stable than men in the ML stance when vision was absent (P < 0.01). Conclusions: Postural sway was altered more significantly on a foam surface than on a firm surface and symmetry between the DL and NDL was observed. Furthermore, we concluded that women have better dynamic balance control than men.

Physiological Mechanisms of Exercise and Its Effects on Postural Sway: Does Sport Make a Difference?

While the effect of a variety of exercises on postural balance control has been extensively studied, less attention has been paid to those requiring sport-specific skills. Therefore there is a need to analyze the literature and elucidate changes in postural balance control after exercises performed in conditions close to a particular sport. This scoping review aims (i) To map the literature that addresses postural sway aspects of acute responses to general and sport-specific exercises and their underlying physiological mechanisms, and (ii) To identify gaps in the existing literature and propose future research on this topic. The main literature search conducted on MEDLINE, Web of Science, Scopus, PubMed, and Cochrane Library databases was completed by SpringerLink, Elsevier, and Google Scholar. A total of 60 articles met the inclusion criteria. Findings identified that among a variety of studies evaluating the effects of exercise on postural balance control, only few of them were conducted under sport-specific conditions (i.e., while shooting in biathlon or pentathlon, and after simulated or match-induced protocols in combat and team sports). Therefore, more research is still needed to address this gap in the literature and aim research at investigation of postural sway response to sport-specific exercises. Further analysis of the literature showed that the type, intensity and duration of exercise play a key role in increased postural sway. Whole body and localized muscular fatigue of the trunk, neck and lower limbs is considered to be a main factor responsible for the magnitude of balance impairment in an initial phase of recovery and speed of its readjustment to a pre-exercise level. Other likely factors affecting postural stability are hyperventilation and deterioration of sensorimotor functions, though some contribution of muscle damage, dehydration, hyperthermia or dizziness cannot be excluded. A better understanding of the physiological mechanisms of balance impairment after exercises performed under simulated fatigue induced protocol, close to conditions specific to a particular sport, has implications for designing smart exercise programs tailored to individual needs to improve athlete performance with high demands on postural stability and/or decrease their risk of injuries.

Caffeine Enhances the Balance System and Postural Balance in Short Time in Healthy Individuals.

Objective:This study aimed to explore the effects of caffeine on balance function by determining the extent to which caffeine consumption affects postural sway and balance control in healthy individuals.Methods:Thirty healthy participants aged 20–35 years without any vestibular disorder were enrolled in this study. The participants were randomly divided into two groups, and those in Group 1 were given two cups of regular coffee (300–350 mg) while those in Group 2 were given two cups of decaffeinated coffee. The sensory organization test, the head shake sensory organization test, the limits of stability test, and the adaptation test were performed on all participants before and after coffee intake using computerized dynamic posturography.Results:The sensory organization test composite scores (p=0.001) and the head shake condition 5 (C5) equilibrium scores (p=0.001) of the participants in Group 1 showed a statistically significant increase after coffee intake while the composite scores (p=0.001) and the head shake condition (C5) equilibrium scores (p=0.001) of those in Group 2 showed a statistically significant decrease. There was a statistically significant difference between the two groups in the equilibrium scores in the pitch plane (p=0.001), the yaw plane (p=0.001), and the roll plane (p=0.001) of C5 after coffee intake.Conclusion:Consumption of an appropriate dose of caffeine may enhance body position, postural stability, and voluntary motor control ability. The combined use of the sensory organization test, the head shake sensory organization test, the adaptation test, and the limits of stability test in evaluating the balance mechanism in individuals with normal vestibular findings provides detailed information about postural sway.

The effect of latin dance on dynamic balance

BackgroundFigures and movements in Latin dance are effectively used to provide posture stabilization and balance control. A Computerized Dynamic Posturography can be used to complete a functional evaluation of postural control and stability in static and dynamic conditions, mediated by the interaction between the visual, vestibular, and somatosensory systems. Research QuestionAccording to the results of Computerized Dynamic Posturography, do dancers have better postural control and stability when compared to non-dancers, and can dance activity be recommended for vestibular rehabilitation? Material and methodsOur study included 26 professional Latin dancers and 26 non-dancers as a control group whoboth had no problems with their hearing or balance. Pure-tone audiometry and Computerized Dynamic Posturography tests were applied to the participants. The test results for the professional dancers and the control group were compared and evaluated. In statistical analysis, the Mann-Whitney U and Independent Samples T tests were used. A value of p < 0.05 was accepted for significance. ResultsAccording to the results of the Computerized Dynamic Posturography, the dancers generally performed better than the control group. While statistically significant and better performances were observed in dancers in terms of the composite balance, visual and vestibular scores within the scope of the Sensory Organization Test (p < 0.05), no statistically significant difference was found for somatosensory and preference scores (p > 0.05). Also, significant differences were obtained between the two groups in some subtests of Adaptation, Unilateral Stance and Limits of Stability assessment (p < 0.05). No significant difference was observed in Rhythmic Weight Shift results (p > 0.05). ImportanceThe results of thisresearch demonstrate that balance and posture improve through dance. Therefore, adding appropriate dance activities to vestibular rehabilitation programmes might be helpful.

Effect of Incorporating Short-Foot Exercises in the Balance Rehabilitation of Flat Foot: A Randomized Controlled Trial.

Effective balance rehabilitation is essential to address flat foot (pes planus) which is closely associated with reduced postural stability. Although sensorimotor training (SMT) and short-foot exercise (SFE) have been effective for improving postural stability, the combined effects of SMT with SFE have not been evaluated in previous studies. The aim of this study was to compare the lone versus combined effects of SMT with SFE on postural stability among participants with flat foot. This was a single-blinded, randomized controlled trial. A total of 32 flat-footed participants were included in the study (14 males and 18 females) and assigned to the SMT combined with SFE group and SMT alone group. All participants underwent 18 sessions of the SMT program three times a week for six weeks. Static balance, dynamic balance, and the Hmax/Mmax ratio were compared before and after the interventions. Static and dynamic balance significantly increased in the SMT combined with SFE group compared with the SMT alone group. However, the Hmax/Mmax ratio was not significantly different between the two groups. Therefore, this study confirms that the combination of SMT and SFE is superior to SMT alone to improve postural balance control in flat-footed patients in clinical settings.

Validity and reliability of standing balance control measurement on the left unilateral spatial neglect model

BACKGROUND: The present study developed a head-mounted display with the visual direction of a web camera modified to the right as a left unilateral spatial neglect (USN) model with respect to postural balance control. AIM: We aimed to estimate the validity and reliability of center of pressure (CoP) measurements in static standing balance (SSB) and dynamic standing balance (DSB) of healthy participants were using the USN model and to examine whether this model's use influenced postural balance control. METHOD: A portable CoP force plate was used to quantify postural balance control in 64 healthy participants as the model. The CoP displacement of the non-USN and USN models in the medial-lateral (ML) and anterior-posterior (AP) planes, CoP length, and bilateral load ratio in SSB and DSB to the right (R) and left (L) were evaluated. RESULTS: Regression analysis indicated that most CoP measurements have excellent concurrent validity. Bland–Altman plots showed good agreement between the non-USN and USN models in the CoP measurements. Test-retest reliability estimation between two times measurements varied in the frontal and sagittal planes. A Comparison of the results demonstrated that the CoP-AP and CoP length changed (-1.40% and 7.67%, respectively) significantly in SSB (P&lt;0.05). Moreover, the CoP-AP changed very significantly in DSB-R and DSB-L (-1.50% and 1.86%, respectively) in opposite directions (P&lt;0.01) when the subjects performed as the model. CONCLUSION: CoP measurements are valid and reliable to quantify standing balance control in both non-USN and USN models that appear to modulate changes in postural adaptation and adjustment.

Exergaming Using Postural Feedback From Wearable Sensors and Exercise Therapy to Improve Postural Balance in People With Nonspecific Low Back Pain: Protocol for a Factorial Pilot Randomized Controlled Trial.

BackgroundPhysical exercise is a common treatment for people with low back pain (LBP). Wearable sensors that provide feedback on body movements and posture during exercise may enhance postural balance and motor control in people with LBP.ObjectiveThis study aims to investigate whether physical exercising with postural feedback (EPF) improves postural balance, motor control, and patient-reported outcomes in people with LBP.MethodsThe study was an assessor-blinded 2×2 factorial trial. We planned to recruit 80 participants with nonspecific LBP who did not receive treatment for LBP. In addition, we aimed to recruit 40 patients with chronic, nonspecific LBP who were receiving exercise therapy (ET) at the University Hospital Zurich. Both ET patients and participants without treatment were randomized to receive either an additional EPF intervention or no additional intervention. This resulted in four different combinations of interventions: ET+EPF, ET, EPF, and no intervention. The participants underwent outcome assessments at inclusion (T1); 3 weeks later, at randomization (T2); after an intervention period of 3 weeks with a predefined exercise schedule for participants receiving EPF (T3); and after an additional 6 weeks, during which participants assigned to the EPF groups could exercise as much as they wished (T4). Patients receiving ET completed their regularly prescribed therapies during the study period. Balance was assessed during quiet standing on a force platform, and motor control was assessed during a lifting task and a waiter’s bow task. Physical activity was recorded using an activity tracker and the participants’ mobile phones during the study. The predefined EPF schedule consisted of nine sessions of 20 minutes of exercise with a tablet and inertial measurement unit sensors at home. Participants performed a series of trunk and hip movements and received feedback on their movements in a gamified environment displayed on the tablet.ResultsThe first participant was recruited in May 2019. Data collection was completed in October 2020, with 3 patients and 32 eligible people without therapy who passed the eligibility check.ConclusionsAlthough it will not be possible to investigate differences in patients and people without other therapies, we expect this pilot study to provide insights into the potential of EPF to improve balance in people with LBP and adherence to such interventions.International Registered Report Identifier (IRRID)DERR1-10.2196/26982

The association of reactive balance control and spinal curvature under lumbar muscle fatigue.

BackgroundAlthough low back fatigue is an important intervening factor for physical functioning among sedentary people, little is known about its possible significance in relation to the spinal posture and compensatory postural responses to unpredictable stimuli. This study investigates the effect of lumbar muscle fatigue on spinal curvature and reactive balance control in response to externally induced perturbations.MethodsA group of 38 young sedentary individuals underwent a perturbation-based balance test by applying a 2 kg load release. Sagittal spinal curvature and pelvic tilt was measured in both a normal and Matthiass standing posture both with and without a hand-held 2 kg load, and before and after the Sørensen fatigue test.ResultsBoth the peak anterior and peak posterior center of pressure (CoP) displacements and the corresponding time to peak anterior and peak posterior CoP displacements significantly increased after the Sørensen fatigue test (all at p < 0.001). A lumbar muscle fatigue led to a decrease of the lumbar lordosis in the Matthiass posture while holding a 2 kg load in front of the body when compared to pre-fatigue conditions both without a load (p = 0.011, d = 0.35) and with a 2 kg load (p = 0.000, d = 0.51). Also the sacral inclination in the Matthiass posture with a 2 kg additional load significantly decreased under fatigue when compared to all postures in pre-fatigue conditions (p = 0.01, d = 0.48). Contrary to pre-fatigue conditions, variables of the perturbation-based balance test were closely associated with those of lumbar curvature while standing in the Matthiass posture with a 2 kg additional load after the Sørensen fatigue test (r values in range from −0.520 to −0.631, all at p < 0.05).ConclusionThese findings indicate that lumbar muscle fatigue causes changes in the lumbar spinal curvature and this is functionally relevant in explaining the impaired ability to maintain balance after externally induced perturbations. This emphasizes the importance for assessing both spinal posture and reactive balance control under fatigue in order to reveal their interrelations in young sedentary adults and predict any significant deterioration in later years.

Are Static and Dynamic Postural Balance Assessments Two Sides of the Same Coin? A Cross-Sectional Study in the Older Adults

The aim of this study was to investigate if the combination of static and dynamic postural balance assessments gives more accurate indications on balance performance among healthy older adults. We also aimed at studying the effect of a dual-task condition on static and dynamic postural balance control. Fifty-seven healthy older adults (age = 73.2 ± 5.0 year, height = 1.66 ± 0.08 m, and body mass = 72.8 ± 13.8 kg) completed the study. Static and dynamic balance were assessed both in single-task and dual-task conditions through a force plate and an oscillating platform. The dominant handgrip strength was also measured with a dynamometer. Pearson’s correlation revealed non-statistically significant correlations between static and dynamic balance performance. The dual-task worsened the balance performance more in the dynamic (+147.8%) than in the static (+25.10%, +43.45%, and +72.93% for ellipse area, sway path, and AP oscillations, respectively) condition (p < 0.001). A weak correlation was found between dynamic balance performance and handgrip strength both in the single (p < 0.05; r = −0.264) and dual (p < 0.05; r = −0.302) task condition. The absence of correlations between static and dynamic balance performance suggests including both static and dynamic balance tests in the assessment of postural balance alterations among older adults. Since cognitive-interference tasks exacerbated the degradation of the postural control performance, dual-task condition should also be considered in the postural balance assessment.

Optical-Based Foot Plantar Pressure Measurement System for Potential Application in Human Postural Control Measurement and Person Identification.

Plantar pressure, the pressure exerted between the sole and the supporting surface, has great potentialities in various research fields, including footwear design, biometrics, gait analysis and the assessment of patients with diabetes. This research designs an optical-based foot plantar pressure measurement system aimed for human postural control and person identification. The proposed system consists of digital cameras installed underneath an acrylic plate covered by glossy white paper and mounted with LED strips along the side of the plate. When the light is emitted from the LED stripes, it deflects the digital cameras due to the pressure exerted between the glossy white paper and the acrylic plate. In this way, the cameras generate color-coded plantar pressure images of the subject standing on the acrylic-top platform. Our proposed system performs personal identification and postural control by extracting static and dynamic features from the generated plantar pressure images. Plantar pressure images were collected from 90 individuals (40 males, 50 females) to develop and evaluate the proposed system. In posture balance evaluation, we propose the use of a posture balance index that contains both magnitude and directional information about human posture balance control. For person identification, the experimental results show that our proposed system can achieve promising results, showing an area under the receiver operating characteristic (ROC) curve of 0.98515 (98.515%), an equal error rate (EER) of 5.8687%, and efficiency of 98.515%.

Vitamin D, Falls and Balance Capacity Impacts in Older Adults: Update

Background Falls injuries continue to contribute to numerous premature deaths as well as high disability levels, and excess morbidity rates among older adults, worldwide. But can vitamin D account for excess falls injuries among older adults? This review specifically focuses on what is known about vitamin D in the context of postural stability or balance control, both fairly consistent independent predictors of falls among older adults. Methods and Procedures Drawn largely from a review of current relevant English language peer reviewed research publications published over the last 10 years detailing the relationship between vitamin D levels and balance control among the elderly, as this relates to falls injuries, evidence for any emerging consensus on this controversial topic was sought. Used to conduct the search were various key word combinations including: falls injuries and older adults, vitamin D or vitamin D deficiency and balance or postural control. The database used predominantly to provide input into this largely descriptive assessment and narrative overview was PUBMED. Results The prevailing data show falls injuries currently constitute a widespread costly major impediment to successful aging and longevity for many older adults, despite numerous efforts to prevent this disabling set of events over the past two to three decades. However, no consistent association appears to exist between the variables of vitamin D, falls, and balance attributes in the older population-despite years of research, regardless of study approach, and a strong rationale for hypothesizing a clinically meaningful relationship. Conclusion It is not possible to arrive at any universal recommendation concerning the value of vitamin D supplementation as regards its possible influence on balance capacity among older adults in the realm of falls prevention efforts, as has been frequently proposed. However, until more definitive research is conducted, there still appears sufficient justification for considering the screening of vulnerable aging adults for serum vitamin D levels, along with balance impairments, and intervening as required in the case of deficits in either or both of these possible falls determinants.

Postural balance and oculomotor control are influenced by neck kinaesthetic functions in elite ice hockey players

BackgroundResearch indicates that neck kinaesthetic awareness plays an important role in oculomotor and balance control, however the relationship has not been studied in athletes. As performance in ice hockey demands visual perception acuity during skating, while constantly shifting between unilateral and bilateral stances in sports specific posture more in-depth relationship should be studied. Research questionWhat is the relationship between neck kinaesthetic awareness, postural balance and eye movement control in professional ice hockey players and non-trained individuals? MethodsIn this observational study, centre-of-pressure was measured using force plate in twenty-eight hockey players and thirty non-trained participants during different stances in eyes-opened and eyes-closed conditions. Butterfly test and Head-to-Neutral Relocation test were performed to assess neck kinaesthesia. Horizontal smooth pursuit eye movements were measured using video-oculography. Linear regression was used to determine the relationship between neck kinaesthesia, body sway and oculomotor control. ResultsTime-on-target in Butterfly test was able to predict low to medium proportions of variance in amplitude and velocity parameters for single leg stances in hockey players (R2 = .220–.698). Head-to-Neutral Relocation test was able to predict low to medium proportion of variance in average eye movement velocity during first 100 milliseconds of smooth pursuit initiation for both groups (R2 = .262–.541). SignificanceFindings from our study suggest that cervical spine afferent input plays an important role in maintaining unilateral postural balance in hockey players, with less evidence presented in controls. Sports specific posture or upper body loading could lead to adaptations in neck proprioception, not frequently considered when searching for balance related injury risk factors or performance deficits. Our study suggests, that in addition to balance control, neck kinaesthesia can also affect oculomotor performance which was present in both groups. This is especially evident when initiating changes in eye movement direction.

Impact of Gender, Change of Base of Support, and Visual Deprivation on Postural Balance Control in Young, Healthy Subjects

Background: Vision, vestibular sense, proprioception and muscle strength are required to maintain balance. However, gender could also play a crucial role in postural sway. Objectives: This study was used to examine (i) the impact of gender, surface type, and vision on postural sway; (ii) the effects of gender and vision on the limb symmetry of postural sway; and (iii) to understand the effects of gender, stance, surface type and vision on the alterations of dynamic postural sway alterations. Methods: This was a cross-sectional study in which young, healthy men (n = 15) and women (n = 12) underwent a balance control assessment using a force plate (SATEL, 40 Hz). Postural stances were evaluated in different conditions: Opened eyes (EO) and closed eyes (EC), on different surface foam vs. firm, a dominant leg stance (DL) vs. a non-dominant leg stance (NDL), and a mediolateral stance (ML) vs. an anteroposterior stance (AP). The mediolateral sway (ML sway), anteroposterior sway (AP sway), and sway area were calculated from the centre of pressure displacements. Results: ML sway, AP sway and sway area increased when eyes were closed (P &lt; 0.000). Foam surface perturbs balance control more than firm surface under EO and EC conditions for both genders, as observed in the AP sway curve (P &lt; 0.000). A functional symmetry exists between the DL and NDL for all sway parameters: The ML sway, AP sway, and sway area (P = 0.720; P = 0.292; P = 0.954). The AP stance is more stable for the ML sway than the ML stance for both genders (P &lt; 0.001). For the AP sway, the ML stance is more stable than the AP sway AP direction stance for both genders (P &lt; 0.001). Women were significantly more stable than men in the ML stance when vision was absent (P &lt; 0.01). Conclusions: Postural sway was altered more significantly on a foam surface than on a firm surface and symmetry between the DL and NDL was observed. Furthermore, we concluded that women have better dynamic balance control than men.

Analysis of Physiological Signals of Individuals with Eyes Closed Subjected to Unexpected Direction-Specific Stimuli Causing Instability

Research regarding the cerebral cortex and muscle activity patterns of the body used for postural balance control when sudden instability stimuli occur is lacking. This study analyzed individuals' physiological signals when direction-specific instability stimuli were applied while their eyes were closed. Healthy adults in their 20s maintained their postural balance while looking at the center of gravity provided by a monitor with a three-dimensional dynamic postural balance training system. We performed electroencephalography (EEG) and measured trunk and lower extremity muscle activity of participants with their eyes closed when subjected to four direction-specific instability stimuli (anterior, posterior, left, and right). EEG results showed that gamma waves increased significantly with an unbalanced stimulus when the participant's eyes were open and closed. The increased gamma wave rate with eyes closed was low in the exercise planning area, where information is relatively integrated and exercise is planned without visual information. EMG results showed fewer gamma waves on EEG due to the low focus on postural control because participants could not observe the center of gravity, which is the basis for balance. The trunk and lower extremity muscles tended to be used more due to the larger body perturbation angle. These outcomes can be used as basic data regarding how the human brain and muscles maintain postural balance when an unexpected external instability stimulus occurs. Quantitative postural balance rehabilitation training protocols for the elderly and those with disabilities can be created based on these outcomes.