Perceptual-motor contributions to static and dynamic balance control in children

Vestibular function and balance performance in children with sensorineural hearing loss

OBJECTIVE

Balance difficulties are common in children with sensorineural hearing loss (SNHL). For some of these children, concomitant vestibular deficits may impact postural control. This study aimed to explore vestibular function, functional balance and postural control, and the relationship between these measures in children with SNHL.

DESIGN

Cross-sectional study quantifying peripheral vestibular function (vestibular evoked myogenic potentials [VEMP], video head impulse test), functional balance (Bruininks-Oseretsky Test of Motor Proficiency [BOT]) and postural control (static posturography with modified sensory inputs). The relationship between the degree of vestibular impairment, functional balance and postural control was explored.

STUDY SAMPLE

Eleven with SNHL, and 11 with normal sound detection (NSD) between 5 and 12 years of age.

RESULTS

Children with SNHL had varying degrees of vestibular dysfunction and differences in overall balance performance. Across all children, greater degrees of vestibular impairment were associated with significantly poorer functional balance and postural control performance for complex standing conditions (BOT percentile rank p = 0.001; compliant surface eyes open [EO]: p = 0.027; compliant surface eyes closed: p = 0.048).

CONCLUSIONS

Vestibular dysfunction in children with SNHL was variable. Vestibular impairment predicted poorer functional balance performance and postural control abilities, including differences in postural sway patterns.

The effect of individual and paired Brailletonik exercises on balance and reaction time in children with intellectual disability

BACKGROUND

children with Intellectual Disabilities (ID) are less proficient in motor skills compared to normally developing children, which means they need more time for learning skills. In this context, the purpose of this research is to investigate the effect of the Brailletonik physical activity program (BPAM) on the balance and reaction time of children with ID.

METHODS

The statistical sample is consisted of 30 children aged 8 to 12 (21 boys, 9 girls) with ID with an average age of 9.8 ± 1.39, who were selected through convenience sampling. Participants were divided into two groups of individual BPAM, and pair BPAM. Training sessions were held for 21 sessions (seven weeks) and each session included 30 min of training. To measure static balance and reaction time, Stork Stand test and Simple Reaction Time Software were used respectively. The analysis of covariance (ANCOVA) and Bonferroni's post hoc test were used to analyze the data. Data analysis was performed using SPSS software version 26 at a significance level of p ≤ 0.05.

RESULTS

The results showed that individual and paired exercise groups had significant progress from pre-test to post-test in both variables of balance and reaction time (p = 0.001). Also, the comparison of the performance of the groups in the post-test showed that the average performance of the paired exercise group was significantly better than the individual exercise group in the balance variable (p = 0.03) and in the reaction time variable (p = 0.01).

CONCLUSION

Accordingly, it can be concluded that BPAM in paired groups has a greater effect on the balance and reaction time of children with ID.

The Effect of a Balance Training Program on the Balance and Technical Skills of Adolescent Soccer Players

Soccer is a complex sport, and balance appears to play a crucial role in the quality execution of technical skills, which are mostly performed while standing on one foot. Nevertheless, in younger ages, when learning still affects soccer performance, the effect of a balance-training program on the player's balance and technical skills remains unexplored. This research examined the effect of a balance-training program (BTP) on balance and technical skills of adolescent soccer players. Τhe participating volunteers were thirty-two soccer players (12-13 years old with 3.84 ± 0.95 years of practice), randomly separated into two groups: an experimental (EXP, n1 = 17) and a control group (CON, n2 = 15). Both groups were evaluated in static and dynamic balance and in technical skills (dribbling, passing, juggling, and shooting with dominant and non-dominant legs) before (Pre-condition) and after the intervention (Post-condition) which was an eight-week BTP for the EXP group and a placebo-training program for the CON group. Α 2 by 2 (groups×condition) mixed analysis of variance (ANOVA) with repeated measures on the condition factor was used to assess possible differences between groups. A significant groups × condition interaction effect was found in dynamic balance (p = 0.008), static (p = 0.042), and shooting (p = 0.022) with dominant leg performance. The EXP group improved (p = 0.007) its static balance by 37.82% and also significantly improved its dynamic balance and shooting accuracy with dominant leg in Post condition by 24.98% (p = 0.006) and 83.84% (p = 0.006) respectively. No significant improvement of other variables was detected in the EXP group Post condition. Dynamic and static balance, and shooting with dominant leg skills can be improved in adolescent soccer players through a specialized 8-week BTP. Balance-training program may contribute to technical skill improvement in soccer training.

Comparison of the immediate effects of plantar vibration of both feet with the plantar vibration of the affected foot on balance in patients with stroke: Preliminary findings

OBJECTIVE

Plantar vibration is one of the strategies to enhance balance in stroke patients. This study compared the effects of the plantar vibration of both feet and the plantar vibration of the most affected side in patients with stroke.

METHODS

This study was a single-blind clinical trial. Post-stroke patients with balance impairment were enrolled in the study and underwent two treatment sessions with a one-week interval. They received both feet's plantar vibration in one session and plantar vibration of the most affected side in the other session (frequency 100 Hz, 5 min). Mini-BESTest, Modified Modified Ashworth Scale (MMAS), and Semmes-Weinstein monofilament examination (SWME) were used to evaluate balance, spasticity, and plantar sensation, before and after the treatment sessions.

RESULTS

Ten patients with a mean age of 52.9 (SD = 5.48) years were enrolled in the study. Mini-BESTest scores of balance and plantar flexor muscle spasticity were significantly improved after both feet plantar vibration and plantar vibration of the more affected side. There was no significant difference between the effectiveness of both sides plantar vibration and the most affected side plantar vibration. There were no significant improvements in SWME sensory scores after plantar vibration of either both sides or the most affected side.

CONCLUSION

Plantar vibration of both sides had no additional benefits in this group of patients with chronic stroke. Plantar vibration of more affected side can be used for improving balance and plantar flexor spasticity post-stroke. The Plantar vibration had no effects on the affected foot sensibility.

Accelerometric analysis of trunk acceleration during gait analysis in children between 6 and 11 years old: A cross-sectional study

Background

Gait analysis in children with accelerometers is of special interest in daily clinical practice, as it eliminates possible biases related to the assessor and is not very sensitivity of visual analysis. The sensitivity of data collection by these instruments makes it possible to evaluate the efficiency of body movements during gait and to better understand the degree of motor development in childhood, assessing progress within normal developmental parameters or detecting possible deficits.

Research question

What are the accelerations of the center of mass during normal gait in children aged 6-11 years?

Methods

Descriptive cross-sectional study conducted with a total of 283 school children (girls = 142). The analyzed variables were the mean and maximum values obtained in each of the three body axes and their root mean square during normal gait 10 m out, turn and 10 m back over firm ground in a straight line three times.

Results

The accelerometric data obtained showed similar values between sexes in each of the age sub-groups analyzed. Except for the medial-lateral axis in children aged 10-11 years where differences between sexes were detected (being significantly lower in girls). A reduction in medial-lateral axis average values over the years was also identified in both sexes. The regression models generated for the average accelerometric values showed significant values only in the average value of the medial-lateral axis. However, the maximum values were significant in all cases.

Significance

The preferred motor strategies of boys and girls during gait include developing mainly control and adjustment movements in the frontal plane (hence the high magnitudes recorded there). Flexion-extension movements are the most reduced over the six years of age analyzed, particularly in girls. Conversely, rotational movements are the most constant in speed in both sexes and all age subgroups.

Therapeutic hypothermia demonstrates sex-dependent improvements in motor function in a rat model of neonatal hypoxic ischemic encephalopathy

Neonatal hypoxic ischemic encephalopathy (HIE) is a neurological disease caused by restricted oxygen and blood flow to the brain at or around the time of birth. Long term cognitive and motor sequelae are common and demonstrate sexual dimorphism in animal studies. Therapeutic hypothermia (TH) is the standard of care for HIE, but provides incomplete neuroprotection. Using the Vannucci model of neonatal HIE, term-equivalent 11-day old rat pups were subjected to mild-moderate hypoxic-ischemic injury (HII), and a subset of animals were treated with TH. Sex-dependent neuroprotection was measured with gross and fine motor control assays, and functional deficits detected with these assays were correlated to injury in specific brain structures. At the equivalent of human adolescence and adulthood (P51-89), accelerod and beam walking tests were used to assess gross motor function, and string-pulling and food handling tests were used to assess fine motor function. At necropsy (P94-97), brain lesions were primarily focused to the posterior cerebrum and characterized by variable reduction in cortical, thalamic and hippocampal regions and glial scarring. Gross motor impairment was detected in male rats with untreated and TH-treated HIE in the accelerod test, but beam walk test data was confounded by the lower body mass of untreated male rats. HIE animals of both sexes demonstrated deficit in the forelimb contralateral to ischemic surgery, observed as unilaterally impaired food handling behaviors, and in string pulling as decreased string contacts and increased in bracing behavior. However, kinematic analyses revealed sex-specific decreases in peak speeds in string reaching and pulling movements. In both sexes, treatment with TH improved body mass, some measures of contralateral forelimb impairment, and the severity of brain lesions to levels not different to Sham surgery rats. Unique differences in behavior following TH were observed in female rats, who took longer to consume food items but traversed beams and approached strings faster than untreated and Sham females. Future use of these motor assays may unravel the subtle, sex-specific differences in HIE outcomes and in developing a customized therapeutic approach to neonatal brain injury.

COMPARISON OF MOTOR PERFORMANCE BETWEEN CHILDREN WITH MULTIPLE DISABILITIES AND TYPICAL DEVELOPMENT

Purpose: Individuals with multiple disabilities have two or more disabilities at the same time, and these impairments can cause qualitatively and quantitatively insufficient motor performance. This study aimed to compare the motor performance of children with multiple disabilities to children with typical development. Methods: This prospective study included 26 children with multiple disabilities who had visual impairment according to the International Statistical Classification of Diseases and Related Health Problems: 11th Revision, and 20 children with typical development. The Bruininks-Oseretsky Test of Motor Proficiency Second Edition Short Form was used to examine motor proficiency. A standard hand dynamometer and pinchmeter were used to assess hand and finger grip strength. The Nine-Hole Peg Test was used to evaluate performance-based hand functions. Results: Children with multiple disabilities had lower scores for balance control (p

Static and Dynamic Balance Indices among Kindergarten Children: A Short-Term Intervention Program during COVID-19 Lockdowns

The COVID-19 pandemic outbreak had a negative impact on kindergarten activities. These young children, who had been compelled to stay home during lockdowns, suffered a lack of movement and loss of mobility, resulting in deteriorated physical motor skills. Lack of sufficient motor experience in early childhood can impair children's motor and cognitive development. Balance skills are fundamental to all other motor abilities, from the most basic movements to the most complex motor skills. The purpose of this study was to implement a short-term physical activity program, which may have a direct effect on children's fundamental balance ability. Ninety-six kindergarten children (45 boys and 51 girls), aged 4-6 years, participated in the study. Data were analyzed using three-way ANOVA and interaction analyses. The results suggest that short, focused, and dedicated balance training programs have a beneficial influence on the static balance of preschoolers and can mitigate some of the negative physical outcomes of lockdowns. In conclusion, this study indicates that a short-term physical training program had a positive effect on the motor abilities of preschoolers after COVID-19-related lockdowns. More research is needed in order to fully understand the complete impact of the worldwide health crisis and the best ways in which to address it.

Tai Chi versus conventional exercise for improving cognitive function in older adults: a pilot randomized controlled trial

Studies have shown that Tai Chi and conventional exercise can modify the brain through distinct mechanisms, resulting in different brain adaptations. Therefore, it is conceivable to speculate that these two exercise modalities may have different effects on improving cognitive function. This study was a parallel group, assessor-blinded, pilot randomized controlled trial comparing the effects of Tai Chi and conventional exercise on improving cognitive function in older persons with mild cognitive impairment (MCI). A total of 34 adults aged ≥ 50 years with MCI were randomized (1:1:1) to the Tai Chi group (TC, n = 10, 3 sessions of 60-min Yang-style Tai Chi training per week for 24 weeks), conventional exercise group (EX: n = 12, 3 sessions of 60-min fitness training per week for 24 weeks), or control group (CON: n = 12, no intervention). Global cognitive function assessed by the Hong Kong version of the Montreal Cognitive Assessment (MoCA-HK) and performance in various cognitive domains were examined at baseline, and 12 and 24 weeks of the intervention. Both exercise groups showed improved global cognitive function as measured by MoCA-HK compared with the control group after 12 and 24 weeks of the intervention, (all P < 0.001). Only TC achieved clinically relevant improvement on global cognitive function at week 12. Both exercise groups achieved clinically relevant improvements at the end of the interventions at week 24. Compared with EX, TC exhibited greater improvements on global cognitive function indicated by MoCA-HK after 12 weeks of the intervention (P < 0.001) and cognitive flexibility indicated by part B/A ratio score of the Trail Making Test throughout the study (all P < 0.05). Both interventions were equally effective in improving the other examined cognitive domains. Further studies are needed to substantiate the superior long-term benefits of Tai Chi on global cognitive function compared with conventional exercise, and dissect the underlying mechanisms of the two exercises on improving cognitive domains and the corresponding brain adaptations. Trial registration: This study was registered at clinicaltrials.gov (Trial registration number: NCT04248400; first registration date: 30/01/2020).

Screening for balance in children and adults in a community science education setting: Normative data, influence of age, sex, and body mass index, and feasibility

BACKGROUND

Screening standing and walking balance is useful for people suspected of having vestibular disorders, a variety of neurologic and musculoskeletal disorders, and for screening astronauts returning after exposure to microgravity. Visitors to a community science education center children and adults, aged 4 to 85, were tested on tandem walking with eyes closed and the modified Romberg test on compliant foam. They were then asked about their experience participating in research, many people for the first time.

METHODS

Subjects performed 10 steps of tandem walking with eyes closed, and three trials of the modified Romberg, or Clinical Test of Sensory Integration and Balance, with eyes closed, standing on compliant memory foam, with a) head still, b) head shaking in yaw, and c) head nodding in pitch. Afterward, staff queried subjects about the experience of participating in science.

RESULTS

Age-related changes across the life span occurred in both sets of tests. Therefore, look-up tables by age are provided. Body mass index significantly affected tandem walking. Some sex differences were found. The tests were easy to administer in a community setting. Most participants enjoyed the experience and reported that they learned about the process of scientific research.

DISCUSSION

These data support and extend the evidence for age-related changes in balance performance across the lifespan and for an influence of body mass index on some balance skills. Clinicians and sports educators should be cognizant of these differences when they use these tests for screening. The community science education environment provided a useful laboratory in which to collect valid and reliable data, while simultaneously educating participants about the process of science.

The effects of exercises with a Pilates ball on balance, reaction time and dual-task performance of kindergarten children

Aim: This study investigated the effects of exercises conducted with a Pilates ball on the motor skills of preschool children. Methods: 62 preschool children were randomly divided into two groups: an intervention group (IG) (n = 30) and a control group (CG) (n = 32). Exercises with a Pilates ball were practiced in IG. The One Leg Standing test, Functional Reach test, Ruler Drop test and Timed-Up and Go test were the outcome measures. Results: Static balance performance and dual-task performance were found to be significantly improved in the intragroup and intergroup comparisons, favoring the IG (p < 0.05). Conclusion: The exercises carried out in this study were found to be effective on static balance and dual-task performance. The study can guide an exercise program for the preschool age group. Clinical Trial Registration: NCT04575441 (ClinicalTrials.gov).

Postural control in adolescent boys and girls before the age of peak height velocity: Effects of task difficulty

BACKGROUND

Adolescent children experience a critical developmental period marked by rapid biological changes. Research question To describe the longitudinal changes in postural control that occur in adolescent boys and girls before the age of peak height velocity (PHV).

METHODS

Here, to address the gap of knowledge, we compared the postural control and activation strategies of the muscles that control the ankle joint in twenty-three boys (age 12.5 ± 0.29) and twenty-one girls (age 10.5 ± 0.32). They performed easy (two legs) and difficult (two legs-eyes closed; one leg) postural balance tasks at 18 and 9 months before PHV and at PHV. We quantified the center of pressure (COP) displacements in the anterior-posterior (AP) and mediolateral (ML) directions and electromyographic (EMG) activity of tibialis anterior (TA) and medial gastrocnemius (MG) muscles.

RESULTS

Boys exhibited greater AP and ML COP displacement than girls only for the one leg task (difficult task). Although boys and girls had similar postural control 18 months prior to PHV, girls exhibited lesser COP displacement at 9 months before PHV, which related to greater TA-MG coactivation (R² = 0.26; p < 0.01). In contrast, postural control was not different between boys and girls with an easy balance task (two legs) performed with eyes open and closed. Rather, we found that all children improved their COP displacement in the ML direction with maturity and both AP and ML COP was significantly lower with eyes open.

CONCLUSION

These findings provide novel evidence that postural control is superior in early adolescent girls than boys 9 months prior to PHV, likely associated with an earlier maturation of muscle coordination.

Static and dynamic postural stability of children girls engaged in modern dance

BACKGROUND

: Postural stability (PS) has an important role in many athletic activities. However, modern dance demands a heightened PS because of the required aesthetic quality and speed of movement. The aim of the present study was to compare the static and dynamic PS of young dancers and participants of other sporting activities.

METHOD

: A total of 101 girls (age: 7.91 ± 0.7 year) were divided into a Dance group (N = 53) and a physically active Control group (N = 48). Static PS was assessed with a two-leg standing test on a Force plate, and dynamic PS was assessed with a Körperkoordinationstest für Kinder (KTK) - a walking backwards test on a balance beam.

RESULTS

: Multivariate analysis of variance showed a general difference between the groups (F = 21.95; p ≤ 0.0001). In static PS, the Dance group was better in Total distance of center of pressure (COP) (p ≤ 0.0001; ES = -1.70), Anterior-posterior oscillation (p ≤ 0.0001; ES = -1.40), Medial-lateral oscillation (p ≤ 0.0001; ES = 1.75) and Length in function of surface (p ≤ 0.0001; ES = -0.98). Both parameters of dynamic stability, the KTK test (p ≤ 0.0001; ES = 1.28) and Motor quotients KTK test (p ≤ 0.0001; ES = 1.45), were significantly better in the Dance group.

CONCLUSION

: The results from the present study indicate that children girls who participate mostly in dance develop better static and dynamic PS than children girls who participate in other sport activities. These findings underline the importance of training modification toward the improvement of PS in dance.

Sex differences in postural control under unstable conditions in schoolchildren with accelerometric assessment

BACKGROUND

Although the effects of balance training on unstable surfaces have been widely studied, the impact of exposure to an unstable surface in static balance throughout childhood has not been described to date.

RESEARCH QUESTION

How does postural stability vary between sexes in children 6-12 years of age during single leg static support on unstable surface? What are the normative values of centre of mass acceleration in the mentioned age range during such test? Is the postural stability on an unstable surface in the postural control of children aged 6-12 years during static single-leg stance. Secondarily, the normative acceleration values of the gravity centre, recorded during such tests and throughout the mentioned age range, were also provided.

METHODS

Descriptive, transversal study conducted with a total of 316 school children (girls = 158). The analysed variables were the mean and maximum values obtained in each of the three body axes and their root mean square during static single-leg support test on an unstable surface (a mat).

FINDINGS

Accelerations decreased in magnitude with the increasing age of the participants. The highest accelerometric values were recorded in the medio-lateral axis in both sexes and throughout the entire age range studied. Between sexes, the greatest differences were obtained between 8 and 11 year-olds. The regression models revealed significant values about the influence of sex on the accelerometric variables (girls were more likely to obtain less accelerations in postural adjustments with increasing age).

INTERPRETATION

Boys depend more on somatoaesthetic information, whereas girls would use more visual and vestibular information. In the age range of 8-11 years, the postural control system is significantly different between sexes regarding the hierarchy of the efferent information of the available postural control subsystems. Moreover, the reactions of straightening and postural control on single-leg stance are, fundamentally, flexion-extension movements.

Gymnastics Experience Enhances the Development of Bipedal-Stance Multi-Segmental Coordination and Control During Proprioceptive Reweighting

Performance and control of upright bipedal posture requires a constant and dynamic integration of relative contributions of different sensory inputs (i. e., sensory reweighting) to enable effective adaptations as individuals face environmental changes and perturbations. Children with gymnastic experience showed balance performance closer to that of adults during and after proprioceptive alteration than children without gymnastic experience when their center of pressure (COP) was analyzed. However, a particular COP sway can be achieved through performing and coordinating different postural movements. The aim of this study was to assess how children and adults of different gymnastic experience perform and control postural movements while they have to adjust balance during and after bilateral tendon vibration. All participants were equipped with spherical markers attached to their skin and two vibrators strapped over the Achilles tendons. Bipedal stance was performed in three 45-s trials in two visual conditions (eyes open, EO, and eyes closed, EC) ordered randomly in which vibration lasted 10 s. Posture movements were analyzed by a principal component analysis (PCA) calculated on normalized and weighted markers coordinates. The relative standard deviation of each principal movement component (principal position, PP-rSTD) quantified its contribution to the whole postural movements, i.e., quantified the coordinative structure. The first (principal velocities, PV-rSTD) and second (principal accelerations, PA-rSTD) time-derivatives characterized the rate-dependent sensory information associated with and the neuromuscular control of the postural movements, respectively. Children without gymnastic experience showed a different postural coordinative structure and different sensory-motor control characteristics. They used less ankle movements in the anterior-posterior direction but increased ankle movements in medio-lateral direction, presented larger hip and trunk velocities, and exhibited more hip actions. Gymnastic experience during childhood seemed to benefit the development of proprioceptive reweighting processes in children, leading to a more mature form of coordinating and controlling posture similarly to adults.

Preschool physical activity and fitness predicts conceptual, verbal and perceptual skills at school

This study investigated longitudinal relationships between physical activity (PA), fitness and cognitive performance at early years. In total, 147 children at the age of 6.6 and 7.6 years participated in the study. PA and sedentary behaviour (SB) were registered with accelerometer. Skinfold thickness measurements were used to assess body composition. Children's cardiorespiratory fitness (CRF), muscular strength and speed-agility fitness was assessed using PREFIT fitness test battery and static balance by EUROFIT test battery. Cognitive skills were measured with modified Boehm-3 test. Linear regression analyses showed that PA at the age of 6.6 years was positively, while SB was negatively associated with the conceptual skills at the age of 7.6 years after adjusting for confounders. Positive associations were observed between CRF, lower-limbs strength relative to fat-free mass, static balance at the age of 6.6 years with perceptual skills at 7.6 years in unadjusted analysis. PA and fitness were not associated with verbal abilities. Physically active lifestyle and CRF, relative explosive strength of the lower limbs, balance at 6.6 years in kindergarten predict conceptual and perceptual skills, but does not predict verbal abilities 1 year later at first grade in school. SB affects negatively conceptual skills.

Influence of Visual Information and Sex on Postural Control in Children Aged 6-12 Years Assessed with Accelerometric Technology

The performance of postural control is believed to be linked to how children use available sensory stimuli to produce adequate muscular activation. Therefore, the aim of the present study was to thoroughly explore postural stability under normal conditions and without visual information in postural control in children aged 6–12 years during static single-leg support. A descriptive cross-sectional study was conducted with 316 children (girls = 158). The analyzed variables were the mean and maximum values obtained in each of the three body axes and their root mean square during two static single-leg support tests: one with eyes open and one with eyes closed. Girls showed lower magnitudes in the recorded accelerations at all ages and in all the variables of both tests. Accelerations during the tests showed progressively lower values from 6 to 12 years of age. The sex had a significant influence on the magnitude obtained in the accelerations recorded during the tests. Improvements in balance with increasing age were greater with visual information than without visual information. The tests of single-leg support showed preferential sensorimotor strategies in boys and girls: boys tend to rely more on visual inputs, and girls process somesthetic information in a preferential way.

Accelerometric Assessment of Postural Balance in Children: A Systematic Review

The correct development of postural control in children is fundamental to ensure that they fully reach their psychomotor capacities. However, this capacity is one of the least studied in the clinical and academic scope regarding children. The objective of this study was to analyze the degree of implementation of accelerometry as an evaluation technique for postural control in children and how it is being used.

METHODS

A systematic search was conducted in PubMed, SpringerLink, SportsDiscus, Medline, Scopus, and Web of Science with the following terms: balance, postural control, children, kids, accelerometry, and accelerometer.

RESULTS

The search generated a total of 18 articles. Two groups of studies were differentiated: those which exclusively included healthy individuals (n = 5) and those which included children with pathologies (n = 13). Accelerometry is being used in children mainly to assess the gait and static balance, as well as to identify the differences between healthy children and children with developmental disorders.

CONCLUSIONS

Accelerometry has a discrete degree of implementation as an evaluation tool to assess postural control. It is necessary to define a systematic method for the evaluation of postural control in pediatrics, in order to delve into the development of this capacity and its alterations in different neurodevelopmental disorders.

Impact of the sensory environment on balance in children with bilateral cochleovestibular loss

BACKGROUND

The aim of the present study was to determine the role of auditory and visual sensory input on balance in children with bilateral cochlevestibular loss. The prevalence of vestibular impairment, and specifically bilateral vestibular loss (BVL) in children with sensorineural hearing loss (SNHL) is high and children with profound cochleovestibular loss (SNHL-BVL) have impaired balance (Suarez et al., 2007; Suarez et al., 2019). Given that both hearing and vestibular impairments are often congenital or acquired in early life, it remains difficult to tease out the individual developmental impact of either one on balance and spatial awareness in children who experience both of these sensory deficits. While cochlear implants (CI) can provide or restore access to sound in children with SNHL-BVL, there is currently no vestibular prosthetic available for clinical use in this population. These children may also use their intact sensory inputs (i.e. vision) to a greater extent to support balance. Alternately, restoring or providing access to sound may, on its own, help these children to balance better. We hypothesized that balance in children with SNHL-BVL who use bilateral CIs is: 1) improved in the presence of directional sound and 2) impaired when visual cues are dynamic (moving) rather than static.

METHODS

Balance was assessed in 18 children with SNHL-BVL and 34 typically developing children with intact vestibular function and normal hearing by performing the Bruininks-Oseretsky Test of Motor Proficiency-2 (BOT-2) balance subtest in a virtual-reality simulator under 4 sensory conditions of graded complexity. Randomized conditions combined 2 auditory (moving directional street sounds vs. directionless static white noise) and 2 visual (dynamic street scene vs. stationary street scene) stimuli designed to recreate a "real-world" busy downtown street. Balance ability in children with SNHL-BVL was also compared with CI on and off.

RESULTS

As expected and similar to previous work, balance was significantly worse in the children with SNHL-BVL compared to typically developing children in all sensory conditions (p<0.0001). As a group, the mean balance skills of the children with SNHL-BVL were equivalent to that of a 4.4-year-old child despite being much older (mean age =13.8 years). Balance ability improved slightly but significantly when children with SNHL-BVL had access to any sound through their CI (p=0.047) and was positively correlated with duration of implant use (p=0.02). Balance ability did not change further in the presence of moving directional sounds compared to static white noise (p=0.42), or when coupled to a moving visual environment (p=0.32) in children with SNHL-BVL, however opposite to what was hypothesized, in the typically developing group, there was a decrement in performance that occurred in the presence of moving directional sound compared to directionless, static white noise (p=0.02).

CONCLUSIONS

Balance ability in children with SNHL-BVL who use bilateral CI was, as expected, poorer than their typically developing peers in all sensory conditions but improved slightly when they had access to any sound through their implants, with this benefit increasing as duration of implant use increased. This suggests that providing sound inputs through bilateral CIs positively affects balance in children with SNHL-BVL where vestibular and/or auditory inputs are compromised. This benefit was achieved even with auditory inputs that were devoid of moving directional cues (i.e. directionless static white noise) and is consistent with poor spatial hearing in children using bilateral CI.

Postural Control during Progressively Increased Balance-Task Difficulty in Athletes with Unilateral Transfemoral Amputation: Effect of Ocular Mobility and Visuomotor Processing

This study examined postural control during single leg stance test with progressively increased balance-task difficulty in soccer players with unilateral transfemoral amputation (n = 11) compared to able-bodied soccer players (n = 11). The overall stability index (OSI), the anterior/posterior stability index, and the medial/lateral stability index during three balance tasks with increasing surface instability were estimated. The oculomotor and visuomotor contribution to postural control in disabled athletes was analyzed. Oculomotor function, simple and choice reaction times, and peripheral perception were assessed in a series of visuomotor tests. The variation in OSI demonstrated significantly greater increases during postural tests with increased balance-task difficulty in the able-bodied soccer players compared to amputees (F_(2,40) = 3.336, p < 0.05). Ocular mobility index correlated (p < 0.05) with OSI in conditions of increasing balance-task difficulty. Moreover, speed of eye-foot reaction has positive influence (p < 0.05) on stability indexes in tasks with an unstable surface. Amputee soccer players displayed comparable postural stability to able-bodied soccer players. Disabled athletes had better adaptability in restoring a state of balance in conditions of increased balance-task difficulty than the controls. The speed of visuomotor processing, characterized mainly by speed of eye-foot reaction, significantly contributed to these results.

Sensory Reweighting During Bipedal Quiet Standing in Adolescents

A cross-sectional, prospective, between-subjects design was used in this study to establish the differences in sensory reweighting of postural control among different ages during adolescence. A total of 153 adolescents (five age groups; 13-17 years old) performed bipedal standing in three sensory conditions (i.e., with visual restriction, vestibular disturbance, and proprioceptive disturbance). Center of pressure displacement signals were measured in mediolateral and anteroposterior directions to characterize reweighting in the sensory system in static postural control when sensory information is disturbed or restricted during adolescent growth. The results indicate a development of postural control, showing large differences between subjects of 13-14 years old and older adolescents. A critical change was found in sensory reweighting during bipedal stance with disturbance of proprioceptive information at 15 years old. Adolescents of 13-14 years old showed less postural control and performance than older adolescents during the disturbance of proprioceptive information. Moreover, the results demonstrated that the visual system achieves its development around 15-16 years old. In conclusion, this research suggests that a difference of sensory reweighting under this type of sensorial condition and sensory reweight systems would seem to achieve stabilization at the age of 15.

Effect of Perceptual Exercise Program on Basic Motor Skills in a Child with Intellectual Disability: Single Subject Research Design

OBJECTIVES The purpose of this study was to identify the effect of perceptual exercise program on basic motor skills in a child with intellectual disability.METHODS One child with intellectual disability was participated in this study. Perceptual exercise program was performed 60 minutes per session, twice a week for 32 weeks. To evaluate the basic motor skills of the subject pre and post the exercise, subject was measured in six areas of operational skills including throwing, catching, kicking, hitting, bouncing, and rolling; two areas of movement skills including balance beam, walking backward; and two areas of stabilization skills including standing with one leg and escaping.RESULTS The subject who participated in this study gained 60% throwing, 60% catching, 80% kicking, 60% hitting, 80% bouncing, and 60% rolling was increased respectively in the operational skills and 80% balance beam, 100% walking backward in the movement skills, and 80% standing with one leg, 100% escaping in the stabilization skills.CONCLUSIONS Those results show that perceptual exercise program was positive influence on operational skills, movement skills and stabilization skills in a child with intellectual disability.

Age and sex differences in human balance performance from 6-18 years of age: A systematic review and meta-analysis

Background

The process of growing leads to inter-individual differences in the timing of growth, maturational, and developmental processes during childhood and adolescence, also affecting balance performance in youth. However, differences in balance performance by age and sex in youth have not been systematically investigated yet.

Objective

The objective of the present study was to characterize and quantify age- and sex-related differences in balance performance in healthy youth.

Methods

A computerized systematic literature search was performed in the electronic databases PubMed, Web of Science, and SPORTDiscus. To be applicable for analysis, studies had to report at least one measure of static steady-state, dynamic steady-state, proactive or reactive balance in healthy children (6–12 years) and/or adolescents (13–18 years). Coding of the studies was done according to the following criteria: age, sex, and balance outcome. Study quality was assessed using the Appraisal tool for Cross-Sectional Studies. Weighted standardized mean differences were calculated and classified according to their magnitude.

Results

Twenty-one studies examined age-related differences in balance performance. A large effect for measures of static steady-state balance (SMD_ba = 1.20) and small effects for proxies of dynamic steady-state (SMD_ba = 0.26) and proactive balance (SMD_ba = 0.28) were found; all in favor of adolescents. Twenty-five studies investigated sex-related differences in balance performance. A small-sized effect was observed for static steady-state balance (SMD_bs = 0.33) in favor of girls and for dynamic steady-state (SMD_bs -0.02) and proactive balance (SMD_bs = -0.15) in favor of boys. Due to a lack of studies, no analysis for measures of reactive balance was performed.

Conclusions

Our systematic review and meta-analysis revealed better balance performances in adolescents compared to children, irrespective of the measure considered. Sex-related differences were inconsistent. These findings may have implications for example in terms of trainability of balance in youth that should be investigated in future studies.

Y-Balance Test Performance and Leg Muscle Activations of Children with Developmental Coordination Disorder

This study compared Lower Quarter Y-Balance Test (YBT-LQ) performance and leg muscle kinetics between children with and without developmental coordination disorder (DCD), and investigated the association between YBT-LQ performance and muscle kinetics in children with DCD. Forty-eight children with DCD and 51 children without DCD participated in the study. Leg muscle kinetics were measured using surface electromyography when performing YBT-LQ. Children with DCD exhibited an overall lower YBT-LQ scores than controls. They had a lower peak gastrocnemius medialis activation for YBT-LQ posteromedial direction and shorter duration for the muscle to reach peak torque for YBT-LQ anterior direction. No relationship was found between YBT-LQ performance and leg muscle activations in children with DCD. Children with DCD exhibited a less competent YBT-LQ performance with atypical neuromuscular control.

Big issues for small feet: developmental, biomechanical and clinical narratives on children's footwear

The effects of footwear on the development of children's feet has been debated for many years and recent work from the developmental and biomechanical literature has challenged long-held views about footwear and the impact on foot development. This narrative review draws upon existing studies from developmental, biomechanical and clinical literature to explore the effects of footwear on the development of the foot. The emerging findings from this support the need for progress in [children's] footwear science and advance understanding of the interaction between the foot and shoe. Ensuring clear and credible messages inform practice requires a progressive evidence base but this remains big issue in children's footwear research.

Age and gymnastic experience effects on sensory reweighting processes during quiet stand

BACKGROUND

The relative contribution of sensory inputs to control balance while standing is dynamically adjusted. These sensory reweighting processes could be impacted by age and sport expertise capabilities, especially when the sport emphasizes equilibrium like artistic gymnastics.

RESEARCH QUESTION

The aim of this study was to explore the sensory reweighting processes to adjust standing posture in children and adults with different gymnastic expertise (gymnasts, G, and non-gymnast, NG).

METHODS

All participants were asked to stand quietly on a force plate in two visual conditions (eyes open, EO, and eyes closed, EC). Within a trial, proprioception was altered with two vibrators strapped at the Achilles tendon level. The center of pressure (COP) displacements in the anterior-posterior and medio-lateral directions were calculated and normalized by the base of support. The effect of vibration application was characterized by the COP speed, maximal posterior displacement and the time when it occurred. The effect of vibration removal was depicted by the time between the motor switched off and the achievement of balance values similar to baseline and the COP speed and movement units performed during this time.

RESULTS

G children presented shorter posterior displacement during vibrations, needed less time to recover initial balance, and produced less movements units than NG children. In general, adults and EO showed better reweighting responses than children and EC, respectively.

SIGNIFICANCE

These results suggest that age could have a positive effect on reweighting processes and that gymnastic experience may benefit the development of proprioceptive reweighting processes in children but not in adults.

Relationship between attention and balance: a dual-task condition study in children

This study explored the relationship between motor functions and attention in children aged 4-5 years. A sample of 85 children was collected from a primary school (44 boys and 41 girls). We applied a standardized continuous attention performance test, the Kiddie Continuous Performance Test, under two conditions (sitting and balancing). Data were collected from two standardized balance tests, the Battelle and Pediatric Balance Scale. There was a significant relationship between attention and balance and gender differences that may condition the way to address balance issues in boys and girls. Gender should be considered when addressing balance problems to get efficient interventions. Balance skill may be a contributing factor in attention-deficit/hyperactivity disorder.

Development of postural control and maturation of sensory systems in children of different ages a cross-sectional study

OBJECTIVE

To evaluate the stability, postural adjustments and contributions of sensory information for postural control in children.

METHODS

40 boys and 40 girls were equally divided into groups of 5, 7, 9 and 12 years (G5, G7, G9 and G12). All children were submitted to dynamic posturography using a modified sensory organization test, using four sensory conditions: combining stable or sway referencing platform with eyes opened, or closed. The area and displacements of the center of pressure were used to determine stability, while the adjustments were used to measure the speed of the center of pressure displacements. These measurements were compared between groups and test conditions.

RESULTS

Stability tends to increase with age and to decrease with sensory manipulation with significant differences between G5 and G7 in different measures. G7 differed from G12 under the conditions of stable and sway platform with eyes open. G9 did not differ from G12. Similar behavior was observed for adjustments, especially in anterior-posterior directions.

CONCLUSION

Postural stability and adjustments were associated with age and were influenced by sensory manipulation. The ability to perform anterior-posterior adjustments was more evident and sensory maturation occurred firstly on the visual system, then proprioceptive system, and finally, the vestibular system, reaching functional maturity at nine years of age. Seven-year-olds seem to go through a period of differentiated singularity in postural control.

Factorial Validity of the Movement Assessment Battery for Children-2nd Edition (MABC-2) in 7-16-Year-Olds

The Movement Assessment Battery for Children-2nd Edition (MABC-2) is a test of motor development, widely used in clinical and research settings. To address which motor abilities are actually captured by the motor tasks in the two age versions of the MABC-2, the AB2 for 7- 10-year-olds and the AB3 for 11- 16-year-olds, we examined AB2 and AB3 factorial validity. We conducted confirmatory factor analysis (SPSS AMOS 22.0) on data from the test's standardization samples of children aged 7-10, n = 483, and 11-16, n = 674, in order to find the best fitting models. The covariance matrix of AB2 and AB3 fit a three-factor model that included tasks of manual dexterity, aiming and catching, and balance. However, factor analytic models fitting AB2 and AB3 did not involve the dynamic balance tasks of hopping with the better leg and hopping with the other leg; and the drawing trail showed very low factor validity. In sum, both AB2 and AB3 of the MABC-2 test are able to discriminate between the three specific motor abilities; but due to questionable psychometric quality, the drawing trail and hopping tasks should be modified to improve the construct validity for both age versions of the MABC-2.

Factorial Structure of the Movement Assessment Battery for Children Test—Second Edition in Preschool Children

The Movement Assessment Battery for Children—Second Edition is one of the most frequently used tests for assessment of the fundamental motor skills in children. However, there is the question which sensorimotor functions are really captured by the tasks involved in the test for the preschool (3–6 years) children (age band 1). The aim of the study was to examine the factorial structure of the age band 1 test. Results of the testing by the age band 1 in a sample of three- to- six-year-old children ( N = 399; 202 boys, 197 girls) were put to confirmatory factor analysis. The results of the study proved the three-specific factor structure of the age band 1. Thus, within the assessment of a child’s overall motor proficiency, the motor competence profile including manual dexterity, aiming and catching, and balance abilities can be identified in three- to six-year-old children.

The effects of dance training program on the postural stability of middle aged women

AIM

The aim of the study was to determine the effects of Greek folk dancing on postural stability in middle age women.

METHODS

Sixty-three women aged from 47-53 participated in this study. All participants were randomly divided into the experimental group - 33 participants (mean ± SD; body height=160.13 ± 12.07 cm, body mass=63.81 ± 10.56 kg), and the control group - 30 participants (mean ± SD; body height=160.63 ± 6.22 cm, body mass=64.79 ± 8.19 kg). The following tests were used to evaluate the motor balance and posture stability of participants; the double-leg stance along the length of a balance beam (eyes open), the double-leg stance along the width of a balance beam (eyes open), the single-leg stance (eyes open) and the double-leg stance on one's toes (eyes closed). The Functional Reach Test for balance and the Star Excursion Balance Test were used to evaluate dynamic balance.

RESULTS

The multivariate analysis of covariance of static and dynamic balance between participants of the experimental and control group at the final measuring, with neutralized differences at the initial measuring (Wilks' λ=0.45), revealed a significant difference (p<0.05). The intergroup difference at the final measuring was also found to be significant (p<0.05) for the following variables; the double-leg stance on one's toes, the Functional Reach Test, balance of the right anterolateral, balance of the right posterolateral and balance of the left posteromedial.

CONCLUSION

An organized dance activity programme does lead to the improvement of static and dynamic balance in middle aged women.

Visual guidance during bicycle steering through narrow lanes: a study in children

Recently, Vansteenkiste et al. (2013) explored how visual behaviour guides bicycle steering when cycling at different speeds through 15m long lanes of 10, 25 and 40cm wide. Participants were found to shift their gaze direction towards the end of the lanes at higher speeds, towards the near pathway on narrow lanes and more towards irrelevant areas on wider lanes. To investigate to what extent young learner bicyclists adapt their visual behaviour in a similar way as adults, the experiment was repeated with seven eight-year-old children, and results were compared to the adult data. Children were found to cycle slower through narrow lanes than adults. However, with increasing lane width and cycling speed, children made the same shifts of visual gaze direction as the adults. These results suggest that for a simple precision steering task, children are able to adopt a similar visual-motor strategy as adults, provided that they cycle at their own pace.

Motion sickness prevalence in school children

This study aimed to determine the prevalence of motion sickness in schoolchildren and related the finding to the postural balance and quality of life. A population-based cross-sectional study was carried out with 831 children aged 7 to 12 years. The frequency of motion sickness was evaluated based on the Motion Sickness Susceptibility Questionnaire-Short (MSSQ-short). Postural balance was assessed using the Romberg test under different sensory conditions. The Dizziness Handicap Inventory was used in order to assess the quality of life. The statistical analyses were performed using the chi-square, Kruskal-Wallis, Mann-Whitney, and Spearman correlation tests. The prevalence of motion sickness was 43.4 % in car, 43.2 % on bus, 11.7 % on park swing, and 11.6 % on Ferris wheel. Mean unadjusted scores on the MSSQ-short ranged from 5.0 (SE = 0.5) for 10-year-olds to 6.8 (SE = 0.5) for 9-year-olds. The most prevalent symptoms following the balance tests were dizziness (89.2 %), vertigo (54.9 %), headache (10.6 %), and nausea (8.2 %). Significant correlations were found between the MSSQ-short score and all postural balance tests. Significant correlations were found between the MSSQ and modified DHI (Dizziness Handicap Inventory) at all ages.

CONCLUSION

The prevalence of motion sickness in schoolchildren is greater when in a car or on a bus. An association was found between motion sickness and postural balance tests and motion sickness and quality of life.

Cycling around a curve: the effect of cycling speed on steering and gaze behavior

Although it is generally accepted that visual information guides steering, it is still unclear whether a curvature matching strategy or a ‘look where you are going’ strategy is used while steering through a curved road. The current experiment investigated to what extent the existing models for curve driving also apply to cycling around a curve, and tested the influence of cycling speed on steering and gaze behavior. Twenty-five participants were asked to cycle through a semicircular lane three consecutive times at three different speeds while staying in the center of the lane. The observed steering behavior suggests that an anticipatory steering strategy was used at curve entrance and a compensatory strategy was used to steer through the actual bend of the curve. A shift of gaze from the center to the inside edge of the lane indicates that at low cycling speed, the ‘look where you are going’ strategy was preferred, while at higher cycling speeds participants seemed to prefer the curvature matching strategy. Authors suggest that visual information from both steering strategies contributes to the steering system and can be used in a flexible way. Based on a familiarization effect, it can be assumed that steering is not only guided by vision but that a short-term learning component should also be taken into account.

Balance in children with attention deficit hyperactivity disorder-combined type

The balance ability in children with attention deficit hyperactivity disorder-combined type (ADHD-C) has not been fully examined, particularly dynamic sitting balance. Moreover, the findings of some published studies are contradictory. We examined the static and dynamic sitting balance ability in 20 children with ADHD-C (mean age: 9 years 3 months; 18 boys, 2 girls) and 20 age-, sex-, height-, weight-, and IQ-matched healthy and typically developing controls (mean age: 9 years 2 months; 18 boys, 2 girls). The balance subtests of the Movement Assessment Battery for Children (MABC) and the Bruininks-Oseretsky Test of Motor Proficiency (BOTMP) were used to compare the two groups, and a mechanical horseback riding test was recorded using a motion-capture system. Compared with the controls, children with ADHD-C had less-consistent patterns of movement, more deviation of movement area, and less-effective balance strategies during mechanical horseback riding. In addition, their performance on the balance subtests of the MABC and BOTMP were not as well as those of the controls. Our findings suggest that balance ability skill levels in children with ADHD-C were generally not as high as those of the controls in various aspects, including static and dynamic balance.

Children's head movements and postural stability as a function of task

Manual dexterity and postural control develop throughout childhood, leading to changes in the synergistic relationships between head, hand and posture. But the postural developments that support complex manual task performance (i.e. beyond pointing and grasping) have not been examined in depth. We report two experiments in which we recorded head and posture data whilst participants simultaneously performed a visuomotor task. In Experiment 1, we explored the extent to which postural stability is affected by concurrently performing a visual and manual task whilst standing (a visual vs. manual-tracking task) in four age groups: 5-6 years (n = 8), 8-9 years (n = 10), 10-11 years (n = 7) and 19-21 years (n = 9). For visual tracking, the children's but not adult's postural movement increased relative to baseline with a larger effect for faster moving targets. In manual tracking, we found greater postural movement in children compared to adults. These data suggest predictive postural compensation mechanisms develop during childhood to improve stability whilst performing visuomotor tasks. Experiment 2 examined the extent to which posture is influenced by manual activity in three age groups of children [5-6 years (n = 14), 7-8 years (n = 25), and 9-10 years (n = 24)] when they were seated, given that many important tasks (e.g. handwriting) are learned and performed whilst seated. We found that postural stability varied in a principled manner as a function of task demands. Children exhibited increased stability when tracing a complex shape (which required less predictive postural adjustment) and decreased stability in an aiming task (which required movements that were more likely to perturb posture). These experiments shed light on the task-dependant relationships that exist between postural control mechanisms and the development of specific types of manual control.

Normal values of functional reach and lateral reach tests in children with knee hypermobility

PURPOSE

To measure values for functional reach (FR) and lateral reach (LR) in school children with knee joint hypermobility (KJH), and to examine the correlation of anthropometric measures and KJH with FR and LR values.

METHODS

A total of 140 children aged 6 to 12 years with typical development (TD) and bilateral KJH of greater than 10° hyperextension participated. Three successive trials of FR and LR tests in standing position with feet shoulder width apart were performed, and the mean of the 3 trials was calculated. Analysis of variance and Bonferroni tests were used to analyze correlation and association of FR and LR values with KJH angle and anthropometric data, respectively, with a 95% confidence interval.

RESULTS

In school-aged children with TD, height and KJH contributed significantly to the FR values in both genders, whereas height contributed for LR values among girls alone.

CONCLUSIONS

Height and KJH affect children's scores on the FR and LR tests of balance.

Modulation between bilateral legs and within unilateral muscle synergists of postural muscle activity changes with development and aging

The effect of development and aging on common modulation between bilateral plantarflexors (i.e., the right and left soleus, and the right and left medial gastrocnemius) (bilateral comodulation) and within plantarflexors in one leg (i.e., the right soleus and the right medial gastrocnemius) (unilateral comodulation) was investigated during bipedal quiet standing by comparing electromyography-electromyography (EMG) coherence among three age groups: adult (23-35 years), child (6-8 years), and elderly (60-80 years). The results demonstrate that there was significant coherence between bilateral plantarflexors and within plantarflexors in one leg in the 0- to 4-Hz frequency region in all three age groups. Coherence in this frequency region was stronger in the elderly group than in the adult group, while no difference was found between the adult and child groups. Of particular interest was the finding of significant coherence in bilateral and unilateral EMG recordings in the 8- to 12-Hz frequency region in some subjects in the elderly group, whereas it was not observed in the adult and child groups. These results suggest that aging affects the organization of bilateral and unilateral postural muscle activities (i.e., bilateral and unilateral comodulation) in the plantarflexors during quiet standing.

The effect of a Stroop-like task on postural control in dyslexic children

The influence of a secondary task on concurrent postural control was explored in twenty-one dyslexic children (mean age: 10.4 ± 0.3 years). Data were compared with twenty age-matched non-dyslexic children. As a secondary task, a modified Stroop test was used, in which words were replaced with pictures of fruits. The postural control of children was recorded in standard Romberg condition as the children were asked to name the colour of fruits appearing consecutively on a computer screen. Two conditions were tested: a congruent condition, in which the fruit was drawn in its natural ripe colour, and a non-congruent colour condition (NC), in which the fruit was drawn in three abnormal colours. A fixating condition was used as baseline. We analyzed the surface, length and mean speed of the center of pressure and measured the number of correct responses in the Stroop-like tasks. Dyslexic children were seen to be significantly more unstable than non-dyslexic ones. For both groups of children, the secondary task significantly increased postural instability in comparison with the fixating condition. The number of correct responses in the modified Stroop task was significantly higher in the non-dyslexic than in the dyslexic group. The postural instability observed in dyslexic children is in line with the cerebellar hypothesis and supports the idea of a deficit in automatic performance in such children. Furthermore, in accordance with cross domain competition model, our findings show that attentional resources are used to a greater extent by the secondary task than in controlling body stability.

Association of postural balance and isometric muscle strength in early- and middle-school-age boys

OBJECTIVE

The purpose of this study was to evaluate the isometric muscle strength (IMS) and dynamic balance in early- and middle-school-age boys and to assess the strength of association between the dynamic balance scores and 6 different IMS indexes.

METHODS

This is a cross-sectional study of a convenience sample of 94 boys who were 6 to 10 years of age and classified into an early school age (6-8 years) group (n = 50) and a middle school age (8-10 years) group (n = 44). Balance was tested using a Biodex Balance System. Anteroposterior Stability Index, Mediolateral Stability Index, and Overall Stability Index were recorded. IMS of 11 muscle groups was measured with a handheld dynamometer and categorized into 6 different muscle strength indices.

RESULTS

The mean (SD) values of anteroposterior, mediolateral, and overall stability indexes observed for all study boys were 1.9 ± 1.0, 1.2 ± 0.7, and 2.5 ± 1.2 respectively. In the middle school age group, strong positive relationships were detected between the overall stability index and trunk, lower limb, anti-gravity, pro-gravity, and total strength indexes (r = -0.86/P < .001, r = -0.91/P < .001, r = -0.88/P < .001, r = -0.83/P < .001, and r = -0.84/P < .001 respectively), while no significant relationship was detected with the upper limb strength index (r = 0.159/P = .303). In the early school age group, moderate positive relationships were detected between the overall stability index and anti-gravity, lower limb, and total strength indexes (r = -0.404/P = .004, r = -0.356/P = .011, and r = -0.350/P = .013 respectively).

CONCLUSION

Dynamic balance did not appear to be mature by the age of 10 years. Better balance skills were recorded in the mediolateral direction than in the anteroposterior direction. In the middle school age group, the overall stability index had positive relationships with almost all examined muscle strength indexes excepting the upper limb strength index.

Balancing on a Slackline: 8-Year-Olds vs. Adults

Children are less stable than adults during static upright stance. We investigated whether the same holds true for a task that was novel for both children and adults and highly dynamic: single-legged stance on a slackline. We compared 8-year-olds with young adults and assessed the following outcome measures: time on the slackline, stability on the slackline (calculated from slackline reaction force), gaze movement, head-in-space rotation and translation, trunk-in-space rotation, and head-on-trunk rotation. Eight-year-olds fell off the slackline quicker and were generally less stable on the slackline than adults. Eight-year-olds also showed more head-in-space rotation and translation, and more gaze variability around a visual anchor point they were instructed to fixate. Trunk-in-space and head-on-trunk rotations did not differ between groups. The results imply that the lower postural stability of 8-year-olds compared to adults – as found in simple upright stance – holds true for dynamic, novel tasks in which adults lack the advantage of more practice. They also suggest that the lack of head and gaze stability constitutes an important limiting factor in children’s ability to master such tasks.

The effects of comprehensive warm-up programs on proprioception, static and dynamic balance on male soccer players

PURPOSE

The study investigated the effects of FIFA 11+ and HarmoKnee, both being popular warm-up programs, on proprioception, and on the static and dynamic balance of professional male soccer players.

METHODS

Under 21 year-old soccer players (n = 36) were divided randomly into 11+, HarmoKnee and control groups. The programs were performed for 2 months (24 sessions). Proprioception was measured bilaterally at 30°, 45° and 60° knee flexion using the Biodex Isokinetic Dynamometer. Static and dynamic balances were evaluated using the stork stand test and Star Excursion Balance Test (SEBT), respectively.

RESULTS

The proprioception error of dominant leg significantly decreased from pre- to post-test by 2.8% and 1.7% in the 11+ group at 45° and 60° knee flexion, compared to 3% and 2.1% in the HarmoKnee group. The largest joint positioning error was in the non-dominant leg at 30° knee flexion (mean error value = 5.047), (p<0.05). The static balance with the eyes opened increased in the 11+ by 10.9% and in the HarmoKnee by 6.1% (p<0.05). The static balance with eyes closed significantly increased in the 11+ by 12.4% and in the HarmoKnee by 17.6%. The results indicated that static balance was significantly higher in eyes opened compared to eyes closed (p = 0.000). Significant improvements in SEBT in the 11+ (12.4%) and HarmoKnee (17.6%) groups were also found.

CONCLUSION

Both the 11+ and HarmoKnee programs were proven to be useful warm-up protocols in improving proprioception at 45° and 60° knee flexion as well as static and dynamic balance in professional male soccer players. Data from this research may be helpful in encouraging coaches or trainers to implement the two warm-up programs in their soccer teams.

Postural control adjustments during progressive inclination of the support surface in children

One of the most important postural challenges in daily life is to continuously correct the destabilizing torque due to gravity that accelerates the body further away from the upright position. This study examined children's (7.9 years old) (n=7) and adults' (n=10) capacity to generate continuous corrective torque during a progressive perturbation. The experimental task was to maintain an upright quiet standing on a platform that gradually and slowly toes-down tilted to a maximum of 14° without visual cues. The vertical forces applied on the platform and the electromyograms from the tibialis anterior and the gastrocnemius were measured. The results showed that children had a different postural response to the perturbation than adults. When the platform was stationary before the inclination, children shifted their body weight backward whereas adults had a more balanced distribution of their weight. During the inclination, children applied a stronger forward force, suggesting a larger postero-anterior displacement of their body weight. Muscular activities were higher in children for both the tibialis anterior and the gastrocnemius, and their tibialis anterior activation profile was different. In conclusion, this study showed that in children aged from 7 to 10 years old neuromuscular responses were not mature enough to generate continuous postural corrective torque in response to the perturbation.

Influence of balance on oral-motor control of speech: a pilot investigation

In this exploratory study, the interaction between motor coordination for balance and oral-motor control for speech was investigated in 31 typical college-aged women, ages 20 to 29 years (M = 22.3, SD = 2.1), recruited through the local university. Since speech is dependent on the control and coordination of the subsystems of the speech production mechanism, it was hypothesized that a difficult balance task would interfere with speech motor control. Oral-motor control was measured by diadochokinesis while participants were in a nonchallenging balance position (floor standing) and a challenging balance position (balance disk on one leg). Results indicated that individuals compensated for speech rate while having to maintain their balance for the syllable repetitions. However, the number of syllables repeated was significantly fewer while on the balance disk. In addition, a correlational analysis indicated that history of speech therapy services was related to poorer balance screening score. Directions for future research are discussed.