Motor strategy during postural control is not muscle fatigue joint-dependent, but muscle fatigue increases postural asymmetry

The aim of this study was to investigate the effects of ankle and hip muscle fatigue on motor adjustments (experiment 1) and symmetry (experiment 2) of postural control during a quiet standing task. Twenty-three young adults performed a bipedal postural task on separate force platforms, before and after a bilateral ankle and hip muscle fatigue protocol (randomized). Ankle and hip muscles were fatigued separately using a standing calf raise protocol (ankle fatigue) on a step and flexion and extension of the hip (hip fatigue) sitting on a chair, at a controlled movement frequency (0.5Hz), respectively. In both experiments, force, center of pressure, and electromyography parameters were measured. The symmetry index was used in experiment 2 to analyze the postural asymmetry in the parameters. Our main findings showed that muscle fatigue impaired postural stability, regardless of the fatigued muscle region (i.e., ankle or hip). In addition, young adults used an ankle motor strategy (experiment 1) before and after both the ankle and hip muscle fatigue protocols. Moreover, we found increased asymmetry between the lower limbs (experiment 2) during the quiet standing task after muscle fatigue. Thus, we can conclude that the postural motor strategy is not muscle fatigue joint-dependent and a fatigue task increases postural asymmetry, regardless of the fatigued region (hip or ankle). These findings could be applied in sports training and rehabilitation programs with the objective of reducing the fatigue effects on asymmetry and improving balance.

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The Effects of Uni- and Bilateral Fatigue on Postural and Power Tasks

Journal of Applied Biomechanics ◽

10.1123/jab.29.1.44 ◽

2013 ◽

Vol 29 (1) ◽

pp. 44-48 ◽

Cited By ~ 7

Author(s):

Paulo H. Marchetti ◽

Maria I.V. Orselli ◽

Marcos Duarte

Keyword(s):

Lower Limb ◽

Healthy Subjects ◽

Postural Sway ◽

Center Of Pressure ◽

Lower Limbs ◽

Quiet Standing ◽

Ground Reaction Forces ◽

Before And After ◽

Reaction Forces ◽

The Mean

The aim of this study was to investigate the effects of unilateral and bilateral fatigue on both postural and power bipedal tasks. Ten healthy subjects performed two tasks: bipedal quiet standing and a maximal bipedal counter-movement jumping before and after unilateral (with either the dominant or nondominant lower limb) and bilateral (with both lower limbs) fatigue. We employed two force plates (one under each lower limb) to measure the ground reaction forces and center of pressure produced by subjects during the tasks. To quantify the postural sway during quiet standing, we calculated the resultant center of pressure (COP) speed and COP area of sway, as well as the mean weight distribution between lower limbs. To quantify the performance during the countermovement jumping, we calculated the jump height and the peak force of each lower limb. We observed that both unilateral and bilateral fatigue affected the performance of maximal voluntary jumping and standing tasks and that the effects of unilateral and bilateral fatigue were stronger in the dominant limb than in the nondominant limb during bipedal tasks. We conclude that unilateral neuromuscular fatigue affects both postural and power tasks negatively.

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Postural Control and Sleep Quality in Cognitive Dual Tasking in Healthy Young Adults

J ◽

10.3390/j4030021 ◽

2021 ◽

Vol 4 (3) ◽

pp. 257-265

Author(s):

Marina Saraiva ◽

Joel Marouvo ◽

Orlando Fernandes ◽

Maria António Castro ◽

João Paulo Vilas-Boas

Keyword(s):

Young Adults ◽

Sleep Quality ◽

Postural Control ◽

Center Of Pressure ◽

Cognitive Task ◽

Quiet Standing ◽

Poor Sleep ◽

Standing Posture ◽

Poor Sleep Quality ◽

Dual Tasking

Although sleep quality disorders can have a negative effect on postural control, studies about this subject are scarce. The aim of this study is to assess the differences in standing posture performance during dual tasking between healthy young adults with a good and poor sleep quality. Thirty-five healthy participants (23.09 ± 3.97 years) performed a postural task (standing posture single task ((ST)) and a dual task (DT): quiet standing while performing a concurrent cognitive task, while the total excursion of the center of pressure (TOTEX CoP), the displacement anterior–posterior (CoP-AP) and medial–lateral (CoP-ML), the mean total velocity displacement of CoP (MVELO CoP) and ellipse sway area (CEA) were measured with a force plate. After assessing the sleep quality with the Pittsburgh Sleep Quality Index, they were divided into two groups (good ((n = 21)) and poor ((n = 14)) sleep quality) to establish comparisons. This study revealed no significant differences in TOTEX CoP, CoP-ML, CoP-AP, MVELO CoP, and CEA among both sleep quality groups. In conclusion, differences in the sleep quality (good or poor sleep quality) among young adults appear not to be a relevant factor in the CoP variation, but the DT versus ST can compromise postural control performance independently of the sleep quality.

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Surface height effects on postural control: A hypothesis for a stiffness strategy for stance*

Journal of Vestibular Research ◽

10.3233/ves-1999-9405 ◽

1999 ◽

Vol 9 (4) ◽

pp. 277-286 ◽

Cited By ~ 8

Author(s):

Mark G. Carpenter ◽

James S. Frank ◽

Cathy P. Silcher

Keyword(s):

Postural Control ◽

Center Of Pressure ◽

High Surface ◽

Quiet Standing ◽

Vestibular Input ◽

Mean Power ◽

Mean Power Frequency ◽

Balance Confidence ◽

Eyes Closed ◽

Ankle Stiffness

One possible factor influencing the control of upright stance is the perceived threat to one's personal safety, i.e. balance confidence. We explored this factor by examining the control of stationary stance when standing on an elevated platform under various conditions of reduced visual and vestibular inputs. Twenty-eight adults (14 male and 14 female, mean age = 23.5 years) participated in the experiment. Postural control was examined by recording the amplitude variability (RMS) and mean power frequency (MPF) of center of pressure excursions (COP) over a 2-minute interval while participants stood in a normal stance on a low (0.19 m) and a high (0.81 m) platform with toes positioned either at or away from the edge of the platform. Vision was manipulated through eyes open and eyes closed trials. Vestibular input was reduced by tilting the head into extension [1]. Anterior-posterior RMS and MPF of COP were significantly influenced by an interaction between surface height and vision. When vision was available, a significant decrease in RMS was observed during quiet standing on a high surface compared to a low surface independent of step restriction. When vision was available MPF increased when subjects were raised from a low to a high surface. The mean position of the COP was significantly influenced by an interaction between height and step restriction. Differences in RMS and MPF responses to height manipulation were observed between genders in eyes closed conditions. Vestibular input influenced postural control at both low and high levels with significant increases in RMS when vestibular input was reduced. The reciprocal changes observed in RMS and MPF suggest modifications to postural control through changes in ankle stiffness. Vision appears to play a role in increasing ankle stiffness when balance confidence is compromised.

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Characteristics of Functional Stability in Young Adolescent Female Artistic Gymnasts

Journal of Human Kinetics ◽

10.2478/hukin-2021-0051 ◽

2021 ◽

Vol 77 (1) ◽

pp. 51-59

Author(s):

Agnieszka Opala-Berdzik ◽

Magdalena Głowacka ◽

Kajetan J. Słomka

Keyword(s):

Postural Control ◽

Center Of Pressure ◽

National Level ◽

Stability Limit ◽

Young Adolescent ◽

Quiet Standing ◽

Adolescent Female ◽

Functional Stability ◽

Postural Control System ◽

Stability Limits

Abstract The aim of this study was to determine whether young adolescent female artistic gymnasts demonstrate better functional stability than age- and sex-matched non-athletes. Different characteristics of the gymnasts’ postural control were expected to be observed. Twenty-two 10- to 13-year-old healthy females (ten national-level artistic gymnasts and twelve non-athletes) participated in the study. To assess their forward functional stability, the 30-s limit of stability test was performed on a force plate. The test consisted of three phases: quiet standing, transition to maximal forward leaning, and standing in the maximal forward leaning position. Between-group comparisons of the directional subcomponents of the root mean squares and mean velocities of the center of pressure and rambling-trembling displacements in two phases (quiet standing and standing in maximal leaning) were conducted. Moreover, anterior stability limits were compared. During standing in maximal forward leaning, there were no differences in the center of pressure and rambling measures between gymnasts and non-athletes (p > 0.05). The values of trembling measures in both anterior-posterior and medial-lateral directions were significantly lower in gymnasts (p < 0.05). Both groups presented similar values for anterior stability limits (p > 0.05). The comparisons of rambling components may suggest a similar supraspinal control of standing in the maximal leaning position between gymnasts and healthy non-athletes. However, decreased trembling in gymnasts may indicate reduced noise in their postural control system possibly due to superior control processes at the spinal level. The anterior stability limit was not influenced by gymnastics training in female adolescents.

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The Effects of Active Self-Correction on Postural Control in Girls with Adolescent Idiopathic Scoliosis: The Role of an Additional Mental Task

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17051640 ◽

2020 ◽

Vol 17 (5) ◽

pp. 1640 ◽

Cited By ~ 1

Author(s):

Elżbieta Piątek ◽

Michał Kuczyński ◽

Bożena Ostrowska

Keyword(s):

Adolescent Idiopathic Scoliosis ◽

Idiopathic Scoliosis ◽

Postural Control ◽

Repeated Measures ◽

Postural Sway ◽

Center Of Pressure ◽

Force Plate ◽

Stroop Test ◽

Quiet Standing ◽

Mental Task

Due to balance deficits that accompany adolescent idiopathic scoliosis (AIS), the potential interaction between activities of daily living and active self-correction movements (ASC) on postural control deserves particular attention. Our purpose was to assess the effects of ASC movements with or without a secondary mental task on postural control in twenty-five girls with AIS. It is a quasi-experimental within-subject design with repeated measures ANOVA. They were measured in four 20-s quiet standing trials on a force plate: no task, ASC, Stroop test, and both. Based on the center-of-pressure (COP) recordings, the COP parameters were computed. The ASC alone had no effect on any of the postural sway measures. Stroop test alone decreased COP speed and increased COP entropy. Performing the ASC movements and Stroop test together increased the COP speed and decreased COP entropy as compared to the baseline data. In conclusion, our results indicate that AIS did not interfere with postural control. The effects of the Stroop test accounted for good capacity of subjects with AIS to take advantage of distracting attentional resources from the posture. However, performing both tasks together exhibited some deficits in postural control, which may suggest the need for therapeutic consultation while engaging in more demanding activities.

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Reliability of Force-Platform Measures of Postural Sway and Expertise-Related Differences

Journal of Sport Rehabilitation ◽

10.1123/jsr.20.4.442 ◽

2011 ◽

Vol 20 (4) ◽

pp. 442-456 ◽

Cited By ~ 13

Author(s):

Zohreh Meshkati ◽

Mehdi Namazizadeh ◽

Mahyar Salavati ◽

Masood Mazaheri

Keyword(s):

Outcome Measures ◽

Postural Sway ◽

Center Of Pressure ◽

Intraclass Correlation ◽

Specific Property ◽

Force Platform ◽

Quiet Standing ◽

Eyes Closed ◽

Before And After ◽

Eyes Open

Context:Although reliability is a population-specific property, few studies have investigated the measurement error associated with force-platform parameters in athletic populations.Objective:To investigate the skill-related differences between athletes and nonathletes in reliability of center-of-pressure (COP) summary measures under eyes-open (EO) and eyes-closed (EC) conditions.Design:Test–retest reliability study.Setting:COP was recorded during double-leg quiet standing on a Kistler force platform before and after a fatiguing treadmill exercise, with EO and EC.Participants:31 male participants including 15 athletes practiced in karate and 16 nonathletes.Main Outcome Measures:Standard deviation (SD) of amplitude, phase-plane portrait, SD of velocity, mean total velocity, and area were calculated from 30-s COP data. Intraclass correlation coefficient (ICC), standard error of measurement, and coefficient of variation (CV) were used as estimates of reliability and precision.Results:Higher ICCs were found for COP measures in the athlete (compared with the nonathlete) group, postfatigued (compared with prefatigued) condition, and EC (compared with EO) tests. CVs smaller than 15% were obtained for most of the COP measures. SD of velocity in the anteroposterior direction showed the highest reliability in most conditions.Conclusions:Tests with EC and to a lesser extent tests performed in the athlete group and in the postfatigued condition showed better reliability.

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The Effect of Fatigue on Single-Leg Postural Sway and Its Transient Characteristics in Healthy Young Adults

Frontiers in Physiology ◽

10.3389/fphys.2021.720905 ◽

2021 ◽

Vol 12 ◽

Author(s):

Žiga Kozinc ◽

Nebojša Trajković ◽

Darjan Smajla ◽

Nejc Šarabon

Keyword(s):

Postural Sway ◽

Center Of Pressure ◽

Transient Behavior ◽

Quiet Standing ◽

Medium Effect ◽

Time Interval ◽

Transient Characteristics ◽

Change Of Direction ◽

Additional Information ◽

Before And After

Neuromuscular fatigue is known to impair balance ability, which is reflected in increased postural sway during quiet standing tasks. Recently, quantifying transient characteristics of postural sway has been suggested as an approach to obtain additional information regarding postural control. However, this approach is currently vastly unexplored. The purpose of this study was to investigate the effects of fatigue (induced by a repeated change of direction task) on postural sway and its transient characteristics during single-leg standing, including whole-trial estimates and indexes of transient behavior in young healthy active adults. The study involved 28 physically active students (14 females). Single-leg postural sway was recorded for 30s before and after a fatiguing protocol, which consisted of a repeated change of direction tasks. We calculated the traditional whole-trial estimates of postural sway [center-of-pressure (CoP) velocity and amplitude in anterior-posterior (AP) and medial-lateral (ML) directions] and corresponding transient behavior indexes, based on three 10-s intervals. Statistically significant sex×fatigue interaction with medium effect sizes was found for whole-trial CoP velocity in AP (p=0.028; η2=0.17) and ML directions (p=0.019; η2=0.19). Post-hoc test showed that both variables substantially decreased in female participants (p=0.041–0.045; d=0.54–0.56), but remained similar in males (p=0.194–0.294). There were small to medium statistically significant main effects of fatigue on transient index for CoP amplitude in both directions (p=0.042–0.049; η2=0.02–0.14). Notably, CoP AP amplitude increased in the first 10-s interval for males (before fatigue: 5.6±1.3mm; after fatigue: 6.3±1.6mm), while the CoP AP amplitude in the third interval remained similar after fatigue (before fatigue: 5.5±1.4mm; after fatigue: 5.1±1.2mm). In conclusion, the responses to fatigue in terms of postural sway were time interval specific, and there were certain sex-differences in responses to fatigue, which could be related to better ability to adapt balance strategies in females. Moreover, our results demonstrate that the indexes of transient behavior could perhaps detect smaller fatigue-induced changes in postural sway that are seen in whole-trial estimates.

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Attentional demands associated with augmented visual feedback during quiet standing

PeerJ ◽

10.7717/peerj.5101 ◽

2018 ◽

Vol 6 ◽

pp. e5101 ◽

Cited By ~ 4

Author(s):

Krzysztof Kręcisz ◽

Michał Kuczyński

Keyword(s):

Postural Control ◽

Visual Feedback ◽

Center Of Pressure ◽

Quiet Standing ◽

Mean Power ◽

Mean Power Frequency ◽

Postural Control System ◽

Power Frequency ◽

Auditory Reaction Time ◽

Anterior Posterior

To investigate how additional visual feedback (VFB) affects postural stability we compared 20-sec center-of-pressure (COP) recordings in two conditions: without and with the VFB. Seven healthy adult subjects performed 10 trials lasting 20 seconds in each condition. Simultaneously, during all trials the simple auditory reaction time (RT) was measured. Based on the COP data, the following sway parameters were computed: standard deviation (SD), mean speed (MV), sample entropy (SE), and mean power frequency (MPF). The RT was higher in the VFB condition (p < 0.001) indicating that this condition was attention demanding. The VFB resulted in decreased SD and increased SE in both the medial-lateral (ML) and anterior-posterior (AP) planes (p < .001). These results account for the efficacy of the VFB in stabilizing posture and in producing more irregular COP signals which may be interpreted as higher automaticity and/or larger level of noise in postural control. The MPF was higher during VFB in both planes as was the MV in the AP plane only (p < 0.001). The latter data demonstrate higher activity of postural control system that was caused by the availability of the set-point on the screen and the resulting control error which facilitated and sped up postural control.

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TEMPORAL AND FRACTAL BEHAVIOR OF THE CENTER OF PRESSURE IN PARKINSONIAN AND HEALTHY ELDERLY COHORTS DURING QUIET STANDING

Journal of Mechanics in Medicine and Biology ◽

10.1142/s0219519420400369 ◽

2020 ◽

Vol 20 (10) ◽

pp. 2040036

Author(s):

SEONHONG HWANG ◽

JAESUN REE ◽

JISUN HWANG

Keyword(s):

Postural Control ◽

Center Of Pressure ◽

Open Loop ◽

Quiet Standing ◽

Fluctuation Analysis ◽

Area Formula ◽

Scaling Exponents ◽

Loop Control ◽

Scaling Properties ◽

Healthy Elderly

This study investigated the quantitative scaling properties of the center of pressure (COP) as well as the spatial-temporal properties of the COP to elucidate the postural control behavior of healthy elderly (HE) adults and adults with Parkinson’s disease (PD) during quiet standing. Eighteen adults with PD and eighteen HE adults participated in this study. The COP movements were recorded while participants stood on either a firm surface or on a foam pad with their eyes either opened or closed. The sway ranges in the anterior–posterior (AP) ([Formula: see text] and medio-lateral (ML) ([Formula: see text] directions, the total length of the trajectory ([Formula: see text], sway area ([Formula: see text], and scaling exponents ([Formula: see text] from detrended fluctuation analysis were computed from the measured COP data. All temporal variables of the COP in all conditions were found to be significantly larger in the PD group than in the HE group. Low scaling exponents obtained for the PD group showed this group possessed diminished postural control ability compared to the HE group. The PD group showed unpredictable open-loop control in both the AP and ML directions. This proprioceptive control became predictable and the time scale relations decreased as the postural challenges increased. The AP and ML closed-loop control of the PD group was more predictable than that of the HE group only when proprioception was distorted using intact visual input, and the visual and proprioceptive inputs were both intact.

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Sensory Reweighting During Bipedal Quiet Standing in Adolescents

Motor Control ◽

10.1123/mc.2018-0119 ◽

2020 ◽

Vol 24 (3) ◽

pp. 383-396

Author(s):

Alberto Pardo-Ibáñez ◽

Jose L. Bermejo ◽

Sergio Gandia ◽

Julien Maitre ◽

Israel Villarrasa-Sapiña ◽

...

Keyword(s):

Postural Control ◽

Center Of Pressure ◽

Age Groups ◽

Sensory System ◽

Sensory Information ◽

Quiet Standing ◽

Proprioceptive Information ◽

Sensory Reweighting ◽

Cross Sectional ◽

Older 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.

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