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Fujio K, Takeuchi Y. Age-Related Changes in Inter-Joint Interactions for Global and Local Kinematics While Standing. IEEE Trans Neural Syst Rehabil Eng 2023; 31:4357-4366. [PMID: 37910410 DOI: 10.1109/tnsre.2023.3328904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2023]
Abstract
Inter-joint interactions are involved in human standing. These interactions work not only for global kinematics that control the center of mass (COM) of the entire body, but also for local kinematics that control joint angular movements. Age-related changes in these interactions are thought to cause unstable standing postures in older people. Interactions of global kinematics are known to be deficient owing to aging. However, it is unclear whether the interaction of local kinematics is affected by aging. We investigated the age-related changes in inter-joint interactions, especially local kinematics, during standing. Differences were investigated in these two inter-joint interactions between older and younger adults in three different postures: normal, eyes-closed, and foam-surface standings. The inter-joint interaction for local kinematics was computed using the induced-acceleration analysis with a double-inverted pendulum model and quantified using an uncontrolled manifold approach. Consistent with previous studies, the inter-joint interaction for COM acceleration (global kinematics) deteriorated in older adults. In contrast, the interactions for angular accelerations in the ankle and hip joints (local kinematics) were slightly better in the older adults. Moreover, the individual components of angular acceleration which were induced by net torques from homonymous and remote joints were significantly increased in older adults. Thus, global and local inter-joint interactions are driven by distinct neural mechanisms and the interaction of local kinematics can compensate for the increment of each component of joint angular acceleration in older adults.
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Azimi R, Abdoli B, Sanjari MA, Khosrowabadi R. Variability of Postural Coordination in Dual-Task Paradigm. J Mot Behav 2023; 56:22-29. [PMID: 37429586 DOI: 10.1080/00222895.2023.2226630] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 05/19/2023] [Accepted: 05/22/2023] [Indexed: 07/12/2023]
Abstract
Postural control is influenced by cognition. In most studies, variability of motor output has been considered regardless of variability in patterns of joint coordination. Uncontrolled manifold framework has been applied to decompose the joint's variance in two components. The first component leaves position of the center of mass in anterior-posterior direction (CoMAP) unchanged (VUCM) while the second component is in charge of variations of CoM (VORT). In this study, 30 healthy young volunteers were recruited. The experimental protocol consisted of three random conditions: quiet standing on a narrow wooden block without a cognitive task (NB), quiet standing on a narrow wooden block with an easy cognitive task (NBE), and quiet standing on a narrow wooden block with a difficult cognitive task (NBD). Results showed that CoMAP sway in NB condition was higher than both NBE and NBD conditions (p = .001). VORT in NB condition was higher than NBE and NBD conditions (p = .003). VORT in NB condition was higher than NBE and NBD conditions (p = .003). VUCM was unchanged in all conditions (p = 1.00) and synergy index in NB condition was smaller than NBE and NBD conditions (p = .006). These results showed that postural synergies increased under dual-task conditions.
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Affiliation(s)
- Rezvan Azimi
- Department of Cognitive and Behavioral Science and Technology in Sport, Faculty of Sport Sciences and Health, Shahid Beheshti University, Tehran, Iran
| | - Behrouz Abdoli
- Department of Cognitive and Behavioral Science and Technology in Sport, Faculty of Sport Sciences and Health, Shahid Beheshti University, Tehran, Iran
| | - Mohammad Ali Sanjari
- Department of Basic Rehabilitation Sciences, School of Rehabilitation Sciences and Biomechanics Lab, Rehabilitation Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Reza Khosrowabadi
- Institute for Cognitive and Brain Sciences, Shahid Beheshti University, Tehran, Iran
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Sadura-Sieklucka T, Czerwosz LT, Kądalska E, Kożuchowski M, Księżopolska-Orłowska K, Targowski T. Is Balance Training Using Biofeedback Effective in the Prophylaxis of Falls in Women over the Age of 65? Brain Sci 2023; 13:brainsci13040629. [PMID: 37190594 DOI: 10.3390/brainsci13040629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 03/27/2023] [Accepted: 04/04/2023] [Indexed: 05/17/2023] Open
Abstract
The paper aims to investigate the usefulness of training in improving mobility and reducing the risk of falls of patients with osteoarthritis by using a force plate and virtual reality as rehabilitation tools. The study involved 72 women randomly divided into two equal groups: the force plate training group, which underwent virtual balance training with visual motor feedback, and the gym training group, which received conventional balance training only. The functional balance assessment was performed before and after the rehabilitation by computerized posturography in a relaxed upright position with open and closed eyes, with visual motor feedback. In the FPT group in the feedback measurement, the mean radius of sways was 30% smaller after rehabilitation (p < 0.00002); the feedback coordination coefficient was more than 10% bigger after rehabilitation (p < 0.001) and reached 92%, which is excellent for elderly people. Total stagnation and stumbling reported by patients decreased after rehabilitation compared to the first examination. Both tested forms of training can contribute to reducing the risk of falls. However, a more significant improvement was obtained in the force plate training group perhaps because the physical effort on a force plate trains the precise movements needed to reposition the centre of gravity without generating excessive inertia forces responsible for loss of balance and falls. Perhaps the most desirable method of intervention is to train a person's ability to perform slow but definite body movements.
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Affiliation(s)
| | - Leszek Tomasz Czerwosz
- Department of Respiration Physiology, Mossakowski Medical Research Institute, Polish Academy of Sciences, 02-106 Warsaw, Poland
| | - Ewa Kądalska
- National Institute of Geriatrics, Rheumatology and Rehabilitation, 02-637 Warsaw, Poland
| | - Marcin Kożuchowski
- National Institute of Geriatrics, Rheumatology and Rehabilitation, 02-637 Warsaw, Poland
| | | | - Tomasz Targowski
- National Institute of Geriatrics, Rheumatology and Rehabilitation, 02-637 Warsaw, Poland
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Andrade V, Mazoni A, Vasconcelos C, Mattos D, Mitra S, Ocarino J, Vaz D. Effects of Age and Attentional Focus on the Performance and Coordination of the Sit-to-Stand Task. J Mot Behav 2022; 55:78-91. [PMID: 36120733 DOI: 10.1080/00222895.2022.2122921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
This study investigated whether age and attentional focus affect synergy organization of sit-to-stand (STS). Young and older adults performed STS while holding a cup under internal (IF) and external focus (EF) instructions. Uncontrolled manifold analysis was used to decompose trial-to-trial variability in joint kinematics into variability that preserves (VUCM) and interferes (VORT) with the horizontal and vertical positions of the center of mass (CoM) and cup. VUCM was significantly higher than VORT for all variables in both age groups and focus conditions. Older adults demonstrated higher VUCM for all variables and higher VORT for all variables except the vertical position of the cup. IF instructions benefited older adults, leading to decreased VORT of the vertical position of CoM and horizontal and vertical positions of the cup.
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Affiliation(s)
- Valéria Andrade
- Center for Cognition, Action, & Perception, Department of Psychology, University of Cincinnati, Cincinnati, Ohio, USA
| | - Alysson Mazoni
- InSySPo, System Innovation Institute of Geosciences, UniversidadeEstadualde Campinas, Campinas, São Paulo, Brazil
| | - Camila Vasconcelos
- Department of Physical Therapy, School of Physical Education, Physical Therapy, and Occupational Therapy, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Daniela Mattos
- Department of Neurology, Washington University School of Medicine in St. Louis, St. Louis, Missouri, USA
| | - Suvobrata Mitra
- Department of Psychology, Nottingham Trent University, Nottingham, UK
| | - Juliana Ocarino
- Department of Physical Therapy, School of Physical Education, Physical Therapy, and Occupational Therapy, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Daniela Vaz
- Department of Physical Therapy, School of Physical Education, Physical Therapy, and Occupational Therapy, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
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Butowicz CM, Yoder AJ, Farrokhi S, Mazzone B, Hendershot BD. Low back pain influences trunk-lower limb joint coordination and balance control during standing in persons with lower limb loss. Clin Biomech (Bristol, Avon) 2022; 92:105580. [PMID: 35124535 DOI: 10.1016/j.clinbiomech.2022.105580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 01/07/2022] [Accepted: 01/13/2022] [Indexed: 02/07/2023]
Abstract
BACKGROUND Balance is sustained through multi-joint coordination in response to postural perturbations. Low back pain alters postural responses; however, it is unknown how coordination between the trunk and lower extremities affects center of mass control during standing balance among persons with limb loss, particularly those with back pain. METHODS Forty participants with unilateral lower limb loss (23 with back pain) stood with eyes open and closed on a firm surface, while wearing IMUs on the sternum, pelvis, and bilaterally on the thigh, shank, and foot. A state-space model with Kalman filter calculated sagittal trunk, hip, knee, and ankle joint angles. Fuzzy entropy quantified center of mass variability of sagittal angular velocity at the sacrum. Normalized cross-correlation functions identified coordination patterns (trunk-hip, trunk-knee, trunk-ankle). Multiple linear regression predicted fuzzy entropy from cross-correlation values for each pattern, with body mass and amputation level as covariates. FINDINGS With eyes open, trunk-lower limb joint coordination on either limb did not predict fuzzy entropy. With eyes closed, positive trunk-hip coordination on the intact limb predicted fuzzy entropy in the pain group (p = 0.02), but not the no pain group. On the prosthetic side, inverse trunk-hip coordination patterns predicted fuzzy entropy in pain group (p = 0.03) only. INTERPRETATION Persons with limb loss and back pain demonstrated opposing coordination strategies between the lower limbs and trunk when vision was removed, perhaps identifying a mechanism for pain recurrence. Vision is the dominant source of balance stabilization in this population, which may increase fall risk when visual feedback is compromised.
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Affiliation(s)
- Courtney M Butowicz
- Research & Surveillance Division, DoD-VA Extremity Trauma & Amputation Center of Excellence, Walter Reed National Military Medical Center, Bethesda, MD, USA.
| | - Adam J Yoder
- Research & Surveillance Division, DoD-VA Extremity Trauma & Amputation Center of Excellence, Naval Medical Center, San Diego, CA, USA
| | - Shawn Farrokhi
- Research & Surveillance Division, DoD-VA Extremity Trauma & Amputation Center of Excellence, Naval Medical Center, San Diego, CA, USA; Department of Rehabilitation Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD, USA
| | - Brittney Mazzone
- Research & Surveillance Division, DoD-VA Extremity Trauma & Amputation Center of Excellence, Naval Medical Center, San Diego, CA, USA; Department of Rehabilitation Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD, USA
| | - Brad D Hendershot
- Research & Surveillance Division, DoD-VA Extremity Trauma & Amputation Center of Excellence, Walter Reed National Military Medical Center, Bethesda, MD, USA; Department of Rehabilitation Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD, USA
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Postural Control and Adaptation Strategy of Young Adults on Unstable Surface. Motor Control 2022; 27:179-193. [PMID: 36216337 DOI: 10.1123/mc.2021-0138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 07/06/2022] [Accepted: 08/10/2022] [Indexed: 11/11/2022]
Abstract
Balance control is essential for postural adjustment in physical activities. This study investigates the behavior of human postural control and the coordination and adaptation strategy of hip, knee, and ankle when standing on an unstable surface. Twenty participants were recruited. Four different conditions were investigated: a quiet bipedal stance with eyes open and eyes closed, and standing on an unstable surface with eyes open and eyes closed. Other than the joint angle, the standard body sway measures, such as sway area and sway velocity, were computed. A nonlinear time series measure, that is, sample entropy, was used to determine the regularity of the time series and body adaptability to change and perturbation. The results show that the body sway increases as the difficulty increases. This study also confirms the coordination of the hip, knee, and ankle to maintain body balance on the unstable surface by decreasing the joint angle and adopting a lower posture. Even though the individual joint has lower sample entropy value and is deemed to be rigid and less adaptive to perturbation, the postural control exhibits higher sample entropy value, particularly in the anterior–posterior direction, and has the ability to stabilize the body by manipulating the joints simultaneously. These outcomes suggest that an unstable surface not only challenges the human postural control, but also reduces the hip, knee, and ankle adaptability to perturbation, thus making it a great tool to train body balance.
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Quijoux F, Nicolaï A, Chairi I, Bargiotas I, Ricard D, Yelnik A, Oudre L, Bertin‐Hugault F, Vidal P, Vayatis N, Buffat S, Audiffren J. A review of center of pressure (COP) variables to quantify standing balance in elderly people: Algorithms and open-access code. Physiol Rep 2021; 9:e15067. [PMID: 34826208 PMCID: PMC8623280 DOI: 10.14814/phy2.15067] [Citation(s) in RCA: 70] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 09/10/2021] [Accepted: 09/14/2021] [Indexed: 12/15/2022] Open
Abstract
Postural control is often quantified by recording the trajectory of the center of pressure (COP)-also called stabilogram-during human quiet standing. This quantification has many important applications, such as the early detection of balance degradation to prevent falls, a crucial task whose relevance increases with the aging of the population. Due to the complexity of the quantification process, the analyses of sway patterns have been performed empirically using a number of variables, such as ellipse confidence area or mean velocity. This study reviews and compares a wide range of state-of-the-art variables that are used to assess the risk of fall in elderly from a stabilogram. When appropriate, we discuss the hypothesis and mathematical assumptions that underlie these variables, and we propose a reproducible method to compute each of them. Additionally, we provide a statistical description of their behavior on two datasets recorded in two elderly populations and with different protocols, to hint at typical values of these variables. First, the balance of 133 elderly individuals, including 32 fallers, was measured on a relatively inexpensive, portable force platform (Wii Balance Board, Nintendo) with a 25-s open-eyes protocol. Second, the recordings of 76 elderly individuals, from an open access database commonly used to test static balance analyses, were used to compute the values of the variables on 60-s eyes-open recordings with a research laboratory standard force platform.
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Affiliation(s)
- Flavien Quijoux
- Centre Borelli UMR 9010/Université Paris‐SaclayENS Paris‐SaclayCNRSSSA, InsermUniversité de ParisParisFrance
- ORPEA GroupPuteauxFrance
| | - Alice Nicolaï
- Centre Borelli UMR 9010/Université Paris‐SaclayENS Paris‐SaclayCNRSSSA, InsermUniversité de ParisParisFrance
| | - Ikram Chairi
- Centre Borelli UMR 9010/Université Paris‐SaclayENS Paris‐SaclayCNRSSSA, InsermUniversité de ParisParisFrance
- Groupe MSDAUniversité Mohammed VI PolytechniqueBenguerirMaroc
| | - Ioannis Bargiotas
- Centre Borelli UMR 9010/Université Paris‐SaclayENS Paris‐SaclayCNRSSSA, InsermUniversité de ParisParisFrance
| | - Damien Ricard
- Centre Borelli UMR 9010/Université Paris‐SaclayENS Paris‐SaclayCNRSSSA, InsermUniversité de ParisParisFrance
- Service de Neurologie de l’Hôpital d’Instruction des Armées de PercySSAClamartFrance
- Ecole du Val‐de‐GrâceEcole de Santé des ArméesParisFrance
| | - Alain Yelnik
- Centre Borelli UMR 9010/Université Paris‐SaclayENS Paris‐SaclayCNRSSSA, InsermUniversité de ParisParisFrance
- PRM DepartmentGH Lariboisière F. WidalAP‐HPUniversité de ParisUMR 8257ParisFrance
| | - Laurent Oudre
- Centre Borelli UMR 9010/Université Paris‐SaclayENS Paris‐SaclayCNRSSSA, InsermUniversité de ParisParisFrance
| | | | - Pierre‐Paul Vidal
- Centre Borelli UMR 9010/Université Paris‐SaclayENS Paris‐SaclayCNRSSSA, InsermUniversité de ParisParisFrance
- Institute of Information and ControlHangzhou Dianzi UniversityZhejiangChina
| | - Nicolas Vayatis
- Centre Borelli UMR 9010/Université Paris‐SaclayENS Paris‐SaclayCNRSSSA, InsermUniversité de ParisParisFrance
| | - Stéphane Buffat
- Laboratoire d’accidentologie de biomécanique et du comportement des conducteursGIE Psa Renault GroupesNanterreFrance
| | - Julien Audiffren
- Department of NeuroscienceUniversity of FribourgFribourgSwitzerland
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Wang IL, Wang LI, Liu Y, Su Y, Yao S, Ho CS. Application of Real-Time Visual Feedback System in Balance Training of the Center of Pressure with Smart Wearable Devices. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:9637. [PMID: 34574560 PMCID: PMC8469963 DOI: 10.3390/ijerph18189637] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/26/2021] [Revised: 09/08/2021] [Accepted: 09/11/2021] [Indexed: 11/16/2022]
Abstract
Balance control with an upright posture is affected by many factors. This study was undertaken to investigate the effects of real-time visual feedback training, provided by smart wearable devices for COP changes for healthy females, on static stance. Thirty healthy female college students were randomly divided into three groups (visual feedback balance training group, non-visual feedback balance training group, and control group). Enhanced visual feedback on the screen appeared in different directions, in the form of fluctuations; the visual feedback balance training group received real-time visual feedback from the Podoon APP for training, while the non-visual feedback balance training group only performed an open-eye balance, without receiving real-time visual feedback. The control group did not do any balance training. The balance training lasted 4 weeks, three times a week for 30 min each time with 1-2 day intervals. After four weeks of balance training, the results showed that the stability of human posture control improved for the one leg static stance for the visual feedback balance training group with smart wearable devices. The parameters of COP max displacement, COP velocity, COP radius, and COP area in the visual feedback balance training group were significantly decreased in the one leg stance (p < 0.05). The results showed that the COP real-time visual feedback training provided by smart wearable devices can better reduce postural sway and improve body balance ability than general training, when standing quietly.
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Affiliation(s)
- I-Lin Wang
- College of Physical Education, Hubei Normal University, Huangshi 435002, China;
| | - Li-I Wang
- Department of Physical Education and Kinesiology, National Dong Hwa University, Hualien 97046, Taiwan;
| | - Yang Liu
- Graduate Institute, Jilin Sport University, No. 2476, Freedom Road, Nanguan District, Changchun 130022, China; (Y.L.); (Y.S.); (S.Y.)
| | - Yu Su
- Graduate Institute, Jilin Sport University, No. 2476, Freedom Road, Nanguan District, Changchun 130022, China; (Y.L.); (Y.S.); (S.Y.)
| | - Shun Yao
- Graduate Institute, Jilin Sport University, No. 2476, Freedom Road, Nanguan District, Changchun 130022, China; (Y.L.); (Y.S.); (S.Y.)
| | - Chun-Sheng Ho
- Division of Physical Medicine and Rehabilitation, Lo-Hsu Medical Foundation, Inc., Lotung Poh-Ai Hospital, Yilan City 26546, Taiwan
- Department of Physical Therapy, College of Medical and Health Science, Asia University, Taichung 41354, Taiwan
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Cruz-Montecinos C, Cuesta-Vargas A, Muñoz C, Flores D, Ellsworth J, De la Fuente C, Calatayud J, Rivera-Lillo G, Soto-Arellano V, Tapia C, García-Massó X. Impact of Visual Biofeedback of Trunk Sway Smoothness on Motor Learning during Unipedal Stance. SENSORS 2020; 20:s20092585. [PMID: 32370050 PMCID: PMC7248825 DOI: 10.3390/s20092585] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Revised: 04/24/2020] [Accepted: 04/27/2020] [Indexed: 12/16/2022]
Abstract
The assessment of trunk sway smoothness using an accelerometer sensor embedded in a smartphone could be a biomarker for tracking motor learning. This study aimed to determine the reliability of trunk sway smoothness and the effect of visual biofeedback of sway smoothness on motor learning in healthy people during unipedal stance training using an iPhone 5 measurement system. In the first experiment, trunk sway smoothness in the reliability group (n = 11) was assessed on two days, separated by one week. In the second, the biofeedback group (n = 12) and no-biofeedback group (n = 12) were compared during 7 days of unipedal stance test training and one more day of retention (without biofeedback). The intraclass correlation coefficient score 0.98 (0.93–0.99) showed that this method has excellent test–retest reliability. Based on the power law of practice, the biofeedback group showed greater improvement during training days (p = 0.003). Two-way mixed analysis of variance indicates a significant difference between groups (p < 0.001) and between days (p < 0.001), as well as significant interaction (p < 0.001). Post hoc analysis shows better performance in the biofeedback group from training days 2 and 7, as well as on the retention day (p < 0.001). Motor learning objectification through visual biofeedback of trunk sway smoothness enhances postural control learning and is useful and reliable for assessing motor learning.
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Affiliation(s)
- Carlos Cruz-Montecinos
- Clinical Biomechanics Laboratory, Department of Physical Therapy, University of Chile, 8380453 Santiago, Chile; (C.C.-M.); (C.M.); (D.F.); (J.E.); (G.R.-L.)
- Biomechanics and Kinesiology Laboratory, Hospital San José, 8380419 Santiago, Chile
| | - Antonio Cuesta-Vargas
- Department of Physiotherapy, Faculty of Heath Sciences, University of Malaga, 29071 Málaga, Spain;
- Institute of Biomedical Research in Malaga (IBIMA), 29010 Málaga, Spain
- School of Clinical Science, Faculty of Health Science, Queensland University Technology, Brisbane, QLD 4000, Australia
| | - Cristian Muñoz
- Clinical Biomechanics Laboratory, Department of Physical Therapy, University of Chile, 8380453 Santiago, Chile; (C.C.-M.); (C.M.); (D.F.); (J.E.); (G.R.-L.)
| | - Dante Flores
- Clinical Biomechanics Laboratory, Department of Physical Therapy, University of Chile, 8380453 Santiago, Chile; (C.C.-M.); (C.M.); (D.F.); (J.E.); (G.R.-L.)
| | - Joseph Ellsworth
- Clinical Biomechanics Laboratory, Department of Physical Therapy, University of Chile, 8380453 Santiago, Chile; (C.C.-M.); (C.M.); (D.F.); (J.E.); (G.R.-L.)
| | - Carlos De la Fuente
- Carrera de Kinesiología, Departamento de Cs. de la Salud, Facultad de Medicina, Pontificia Universidad Católica, 7820436 Santiago, Chile;
- Laboratorio LIBFE, Escuela de Kinesiología, Universidad de los Andes, 7620086 Santiago, Chile
- Centro de Salud Deportiva, Clínica Santa María, 7520378 Santiago, Chile
| | - Joaquín Calatayud
- Exercise Intervention for Health Research Group (EXINH-RG), Department of Physiotherapy, University of Valencia, 46010 Valencia, Spain;
| | - Gonzalo Rivera-Lillo
- Clinical Biomechanics Laboratory, Department of Physical Therapy, University of Chile, 8380453 Santiago, Chile; (C.C.-M.); (C.M.); (D.F.); (J.E.); (G.R.-L.)
- Neuroscience Department, University of Chile, 8380453 Santiago, Chile
- Research and Development Unit, Clínica Los Coihues, 9190025 Santiago, Chile
| | | | - Claudio Tapia
- Clinical Biomechanics Laboratory, Department of Physical Therapy, University of Chile, 8380453 Santiago, Chile; (C.C.-M.); (C.M.); (D.F.); (J.E.); (G.R.-L.)
- Universidad Tecnológica de Chile INACAP, Escuela Salud, 8340536 Santiago, Chile
- Correspondence:
| | - Xavier García-Massó
- Human Movement Analysis Group (HuMAG), University of Valencia, 46022 Valencia, Spain;
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Camara CTP, de Freitas SMSF, Lima CA, Amorim CF, Prado-Rico JM, Perracini MR. The walking cane length influences the postural sway of community-dwelling older women. PHYSIOTHERAPY RESEARCH INTERNATIONAL 2019; 25:e1804. [PMID: 31322813 DOI: 10.1002/pri.1804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Revised: 04/30/2019] [Accepted: 07/04/2019] [Indexed: 11/12/2022]
Abstract
BACKGROUND Mobility-related problems in older people may be relieved by the use of walking canes. However, the influence of the cane length on the postural stability of cane users has not been explored. OBJECTIVE The objective of this study is to examine the influence of a single-point cane with different lengths on the postural sway of regular cane users, older women during two stance positions, with feet parallel and semi-tandem stance. METHODS Eighteen older women, who used a single-point walking cane for at least 6 months, stood on a force plate with feet parallel or in semitandem position for 40 s. They always used a cane that was adjusted to one of three different lengths resulting from the distance between the wrist crease and the floor, named WF, or this distance plus 7.5 or 10 cm. Amplitude and speed of the centre of pressure (COP) and its components (rambling and trembling) in the anterior-posterior and medial-lateral directions and mean vertical force applied to the cane were compared across cane lengths. RESULTS The amplitude and velocity of COP, rambling and trembling increased with the cane length. This effect was observed for the anterior-posterior with the feet parallel and in the medial-lateral direction with the semi-tandem position. More force was applied on the shorter cane (WF) in semitandem position. CONCLUSION Longer canes increased the postural sway in the older women and restricted the body weight loaded on the cane. Improper cane length influences the postural sway particularly in a semitandem stance of regular cane users. This may cause a negative impact on postural stability required in daily life activities. The current findings may contribute to the prescription of this assistive device for older adults.
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Affiliation(s)
- Camila Thais Pinto Camara
- Master's and Doctoral Programs in Physical Therapy, Universidade Cidade de São Paulo, São Paulo, Brazil
| | - Sandra Maria Sbeghen Ferreira de Freitas
- Master's and Doctoral Programs in Physical Therapy, Universidade Cidade de São Paulo, São Paulo, Brazil.,Department of Kinesiology, The Pennsylvania State University, PA, USA
| | - Camila Astolphi Lima
- Master's and Doctoral Programs in Physical Therapy, Universidade Cidade de São Paulo, São Paulo, Brazil
| | - César Ferreira Amorim
- Master's and Doctoral Programs in Physical Therapy, Universidade Cidade de São Paulo, São Paulo, Brazil
| | | | - Monica Rodrigues Perracini
- Master's and Doctoral Programs in Physical Therapy, Universidade Cidade de São Paulo, São Paulo, Brazil.,Master's and Doctoral Programs in Gerontology, Faculty of Medicine, Universidade Estadual de Campinas, São Paulo, Brazil
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Abstract
The aim of this study was to investigate the relationship between postural regulation and tracking accuracy under static and moving visual target conditions in unipedal and bipedal standing postures. Postural time-to-contact stability boundaries decreased under more challenging visual target conditions for the unipedal posture, but this decrease was associated with lower visual tracking error. During bipedal support, there was independent control of the head and foot center of pressure, as higher frequencies at the head during the static visual task were associated with longer time-to-contact. These results demonstrate that decreased time-to-contact stability boundaries is a functional adaptation in postural tasks requiring visual control and provide evidence of the dependency of postural control on the nature of the suprapostural task.
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Yamagata M, Tateuchi H, Shimizu I, Saeki J, Ichihashi N. The relation between limb segment coordination during walking and fall history in community-dwelling older adults. J Biomech 2019; 93:94-100. [PMID: 31272683 DOI: 10.1016/j.jbiomech.2019.06.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Revised: 06/17/2019] [Accepted: 06/17/2019] [Indexed: 11/28/2022]
Abstract
Control of the swing foot during walking is important to prevent falls. The trajectories of the swing foot are adjusted by coordination of the lower limbs, which is evaluated with uncontrolled manifold (UCM) analysis. A previous study that applied this analysis to walking revealed that older adults with fall history had compensatorily great segment coordination to stabilize the swing foot during normal walking. However, it is unknown whether the increase in segment coordination helps for preventing incident falls in the future. At baseline measurement, 30 older adults walked for 20 times at a comfortable speed. UCM analysis was performed to evaluate how the segment configuration in the lower limbs contributes to the swing foot stability. One year after the baseline visit, we asked the subjects if there were incident falls through a questionnaire. The univariate and multivariable logistic regression analyses were performed to assess the association between the index of segment coordination and incident falls with and without adjustment for gait velocity. Twenty-eight older adults who responded to the questionnaire were classified into older adults (n = 12) who had the incident fall and those (n = 16) who did not have falls. It was revealed that older adults who increased the segment coordination associated with swing foot stability tended to experience at least one fall within one year of measurement. The index of the UCM analysis can be a sensitive predictor of incident falls.
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Affiliation(s)
- Momoko Yamagata
- Human Health Science, Graduate School of Medicine, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo, Kyoto 606-8507, Japan; Research Fellow of the Japan Society for the Promotion of Science, 5-3-1 Kojimachi, Chiyodaku, Tokyo 102-0083, Japan.
| | - Hiroshige Tateuchi
- Human Health Science, Graduate School of Medicine, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo, Kyoto 606-8507, Japan
| | - Itsuroh Shimizu
- Fukui General Clinic, 1-42-1 Nittazuka, Fukui-shi, Fukui 910-0067, Japan
| | - Junya Saeki
- Faculty of Sport Sciences, Waseda University, 2-579-15 Mikajima, Tokorozawa, Saitama 359-1192, Japan; Research Fellow of the Japan Society for the Promotion of Science, 5-3-1 Kojimachi, Chiyodaku, Tokyo 102-0083, Japan
| | - Noriaki Ichihashi
- Human Health Science, Graduate School of Medicine, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo, Kyoto 606-8507, Japan
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Li R, Walter HJ, Stoffregen TA. The Role of Visual Feedback about Motion of the Ground on Postural Sway. J Mot Behav 2019; 52:352-359. [DOI: 10.1080/00222895.2019.1627281] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- Ruixuan Li
- School of Kinesiology, University of Minnesota, Minneapolis, MN, USA
| | - Hannah J. Walter
- School of Kinesiology, University of Minnesota, Minneapolis, MN, USA
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Greve C, Hortobágyi T, Bongers RM. Flexibility in joint coordination remains unaffected by force and balance demands in young and old adults during simple sit-to-stand tasks. Eur J Appl Physiol 2019; 119:419-428. [PMID: 30474739 PMCID: PMC6373350 DOI: 10.1007/s00421-018-4035-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Accepted: 11/13/2018] [Indexed: 11/10/2022]
Abstract
PURPOSE We examined the possibility that old adults use flexibility in joint coordination as a compensatory mechanism for the age-related decline in muscle strength when performing the sit-to-stand (STS) task repeatedly under high force and balance demands. METHOD Young (n = 14, 22.4 ± 2.1) and old (n = 12, 70 ± 3.2) healthy adults performed repeated STSs under high and low force and balance demands. The balance demand was manipulated by reducing the base of support and the force demand by increasing body weight with a weight vest. Uncontrolled manifold analysis was used to quantify age differences in motor flexibility. RESULTS While there were age-typical differences in kinematic STS strategies, flexibility in joint coordination was independent of age and task difficulty during repeated STSs. DISCUSSION That simple manipulations of force and balance demands did not affect flexibility in joint coordination in old and young adults suggests that motor flexibility acts as a compensatory mechanism only at the limits of available muscle strength and balance abilities during STS movements. Intervention studies should identify how changes in specific neuromuscular functions affect flexibility in joint coordination during activities of daily living such as STS.
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Affiliation(s)
- Christian Greve
- Center for Human Movement Science, University of Groningen, University Medical Center Groningen, Hanzeplein 1, HPC CB41, Postbus 30.001, 9700 RB, Groningen, The Netherlands.
- Department of Rehabilitation Medicine, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
| | - Tibor Hortobágyi
- Center for Human Movement Science, University of Groningen, University Medical Center Groningen, Hanzeplein 1, HPC CB41, Postbus 30.001, 9700 RB, Groningen, The Netherlands
| | - Raoul M Bongers
- Center for Human Movement Science, University of Groningen, University Medical Center Groningen, Hanzeplein 1, HPC CB41, Postbus 30.001, 9700 RB, Groningen, The Netherlands
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Garbus RBSC, Alouche SR, Prado-Rico JM, Aquino CM, Freitas SMSF. From One to Two: Can Visual Feedback Improve the Light Touch Effects on Postural Sway? J Mot Behav 2018; 51:532-539. [PMID: 30395794 DOI: 10.1080/00222895.2018.1528201] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The postural control is improved by implicit somatosensory information from lightly touching a rigid bar or explicit visual information about the postural sway. Whether these two additional sources provided at the same time further reduce the postural sway is still unknown. Participants stood on a force plate as quiet as possible lightly touching the bar while received or not visual feedback of the center of pressure position on a monitor screen. Postural sway reduced similarly with the light touch regardless of the additional visual feedback. The findings suggested that providing explicit visual feedback of the center of pressure does not increase the light touch effects on the postural sway. The importance of the implicit somatosensory information on postural control is discussed.
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Affiliation(s)
- Rafaela B S C Garbus
- a Graduate Program in Physical Therapy , Universidade Cidade de São Paulo , São Paulo , Brazil
| | - Sandra R Alouche
- a Graduate Program in Physical Therapy , Universidade Cidade de São Paulo , São Paulo , Brazil
| | - Janina M Prado-Rico
- a Graduate Program in Physical Therapy , Universidade Cidade de São Paulo , São Paulo , Brazil
| | - Camila M Aquino
- a Graduate Program in Physical Therapy , Universidade Cidade de São Paulo , São Paulo , Brazil
| | - Sandra M S F Freitas
- a Graduate Program in Physical Therapy , Universidade Cidade de São Paulo , São Paulo , Brazil .,b Department of Kinesiology , The Pennsylvania State University , University Park , Pennsylvania , USA .,c Department of Neurology , The Pennsylvania State University - Milton S. Hershey Medical Center , Hershey , Pennsylvania , USA
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16
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Li R, Peterson N, Walter HJ, Rath R, Curry C, Stoffregen TA. Real-time visual feedback about postural activity increases postural instability and visually induced motion sickness. Gait Posture 2018; 65:251-255. [PMID: 30558940 DOI: 10.1016/j.gaitpost.2018.08.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Revised: 07/24/2018] [Accepted: 08/07/2018] [Indexed: 02/02/2023]
Abstract
BACKGROUND Several studies have shown that the kinematics of standing body sway can be influenced by the provision of real time feedback about postural activity through visual displays. RESEARCH QUESTION We asked whether real time visual feedback about the position of the body's center of pressure (COP) might affect body sway and the occurrence of visually induced motion sickness. METHODS Standing participants (women) were exposed to complex visual oscillation in a moving room, a device that nearly filled the field of view. During exposure to complex visual oscillations, we provided real time feedback about displacements of the body's center of pressure through a visual display presented on a tablet computer. RESULTS The incidence of motion sickness was greater than in a closely related study that did not provide real time feedback. We monitored the kinematics of the body's center of pressure before and during exposure to visual motion stimuli. Body sway differed between participants who reported motion sickness and those who did not. These differences existed before any participants experienced subjective symptoms of motion sickness. SIGNIFICANCE Real time visual feedback about COP displacement did not reduce visually induced motion sickness, and may have increased it. We identified postural precursors of motion sickness that may have been exacerbated by the COP display. The results indicate that visual feedback about postural activity can destabilize postural control, leading to negative side effects. We suggest possible alternative types of visual displays that might help to stabilize posture, and reduce motion sickness.
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Affiliation(s)
- Ruixuan Li
- School of Kinesiology, University of Minnesota, USA
| | | | | | - Ruth Rath
- School of Kinesiology, University of Minnesota, USA
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Imaizumi S, Asai T, Hiromitsu K, Imamizu H. Voluntarily controlled but not merely observed visual feedback affects postural sway. PeerJ 2018; 6:e4643. [PMID: 29682421 PMCID: PMC5909687 DOI: 10.7717/peerj.4643] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Accepted: 03/29/2018] [Indexed: 12/04/2022] Open
Abstract
Online stabilization of human standing posture utilizes multisensory afferences (e.g., vision). Whereas visual feedback of spontaneous postural sway can stabilize postural control especially when observers concentrate on their body and intend to minimize postural sway, the effect of intentional control of visual feedback on postural sway itself remains unclear. This study assessed quiet standing posture in healthy adults voluntarily controlling or merely observing visual feedback. The visual feedback (moving square) had either low or high gain and was either horizontally flipped or not. Participants in the voluntary-control group were instructed to minimize their postural sway while voluntarily controlling visual feedback, whereas those in the observation group were instructed to minimize their postural sway while merely observing visual feedback. As a result, magnified and flipped visual feedback increased postural sway only in the voluntary-control group. Furthermore, regardless of the instructions and feedback manipulations, the experienced sense of control over visual feedback positively correlated with the magnitude of postural sway. We suggest that voluntarily controlled, but not merely observed, visual feedback is incorporated into the feedback control system for posture and begins to affect postural sway.
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Affiliation(s)
- Shu Imaizumi
- Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan.,Japan Society for the Promotion of Science, Tokyo, Japan
| | - Tomohisa Asai
- Cognitive Mechanisms Laboratories, Advanced Telecommunications Research Institute International, Kyoto, Japan
| | | | - Hiroshi Imamizu
- Cognitive Mechanisms Laboratories, Advanced Telecommunications Research Institute International, Kyoto, Japan.,Graduate School of Humanities and Sociology, The University of Tokyo, Tokyo, Japan
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18
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Li R, Walter H, Curry C, Rath R, Peterson N, Stoffregen TA. Postural time-to-contact as a precursor of visually induced motion sickness. Exp Brain Res 2018; 236:1631-1641. [DOI: 10.1007/s00221-018-5246-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2017] [Accepted: 03/23/2018] [Indexed: 12/01/2022]
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19
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Takeda K, Mani H, Hasegawa N, Sato Y, Tanaka S, Maejima H, Asaka T. Adaptation effects in static postural control by providing simultaneous visual feedback of center of pressure and center of gravity. J Physiol Anthropol 2017; 36:31. [PMID: 28724444 PMCID: PMC5518099 DOI: 10.1186/s40101-017-0147-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Accepted: 07/04/2017] [Indexed: 11/10/2022] Open
Abstract
Background The benefit of visual feedback of the center of pressure (COP) on quiet standing is still debatable. This study aimed to investigate the adaptation effects of visual feedback training using both the COP and center of gravity (COG) during quiet standing. Methods Thirty-four healthy young adults were divided into three groups randomly (COP + COG, COP, and control groups). A force plate was used to calculate the coordinates of the COP in the anteroposterior (COPAP) and mediolateral (COPML) directions. A motion analysis system was used to calculate the coordinates of the center of mass (COM) in both directions (COMAP and COMML). The coordinates of the COG in the AP direction (COGAP) were obtained from the force plate signals. Augmented visual feedback was presented on a screen in the form of fluctuation circles in the vertical direction that moved upward as the COPAP and/or COGAP moved forward and vice versa. The COP + COG group received the real-time COPAP and COGAP feedback simultaneously, whereas the COP group received the real-time COPAP feedback only. The control group received no visual feedback. In the training session, the COP + COG group was required to maintain an even distance between the COPAP and COGAP and reduce the COGAP fluctuation, whereas the COP group was required to reduce the COPAP fluctuation while standing on a foam pad. In test sessions, participants were instructed to keep their standing posture as quiet as possible on the foam pad before (pre-session) and after (post-session) the training sessions. Results In the post-session, the velocity and root mean square of COMAP in the COP + COG group were lower than those in the control group. In addition, the absolute value of the sum of the COP − COM distances in the COP + COG group was lower than that in the COP group. Furthermore, positive correlations were found between the COMAP velocity and COP − COM parameters. Conclusions The results suggest that the novel visual feedback training that incorporates the COPAP–COGAP interaction reduces postural sway better than the training using the COPAP alone during quiet standing. That is, even COPAP fluctuation around the COGAP would be effective in reducing the COMAP velocity.
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Affiliation(s)
- Kenta Takeda
- Graduate School of Health Sciences, Hokkaido University, N12-W5, Kita-ku, Sapporo, Hokkaido, 060-0812, Japan
| | - Hiroki Mani
- Department of Rehabilitation Science, Faculty of Health Sciences, Hokkaido University, N12-W5, Kita-ku, Sapporo, Hokkaido, 060-0812, Japan
| | - Naoya Hasegawa
- Graduate School of Health Sciences, Hokkaido University, N12-W5, Kita-ku, Sapporo, Hokkaido, 060-0812, Japan
| | - Yuki Sato
- Graduate School of Health Sciences, Hokkaido University, N12-W5, Kita-ku, Sapporo, Hokkaido, 060-0812, Japan
| | - Shintaro Tanaka
- Graduate School of Health Sciences, Hokkaido University, N12-W5, Kita-ku, Sapporo, Hokkaido, 060-0812, Japan
| | - Hiroshi Maejima
- Department of Rehabilitation Science, Faculty of Health Sciences, Hokkaido University, N12-W5, Kita-ku, Sapporo, Hokkaido, 060-0812, Japan
| | - Tadayoshi Asaka
- Department of Rehabilitation Science, Faculty of Health Sciences, Hokkaido University, N12-W5, Kita-ku, Sapporo, Hokkaido, 060-0812, Japan.
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20
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D'Anna C, Schmid M, Scorza A, Goffredo M, Sciuto SA, Conforto S. Can a Visual Biofeedback system based on predictive information improve postural performance? ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2016; 2015:6951-4. [PMID: 26737891 DOI: 10.1109/embc.2015.7319991] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The aim of this study is to assess if predictive information can be used to implement visual biofeedback (VBF) systems to improve postural performance. The Centre of Pressure (CoP) coordinates, extracted directly from a force plate, are used to implement two different realtime VBF, which respectively use current CoP coordinates (VBF(real_time)) and predictive stability information (VBF(predictive)). Predictive coordinates are calculated in agreement with time-to collision theory, using the real-time CoP components. In both VBF, subjects know if they are or are not in the stability area by an emoticon image displayed on the computer monitor. The expression of emoticon was smiling if the CoP coordinates were inside the area of stability, it was sad if the CoP coordinates exceed the stability area. Two groups of eighteen healthy young subjects performed the protocol in two different sequences: noVBF-VBF(real_time) and noVBF-VBF(predictive). Each condition was repeated three times, and its effect was studied by four parameters extracted directly from CoP coordinates (sway path, sway area, mean amplitude and mean frequency). Both VBFs determine a modification of postural parameters compared to the baseline condition (noVBF) with decrease of sway area and mean amplitude and increase of mean frequency. The comparison between the two VBFs shows significant difference for all parameters except for mean frequency. In particular, sway path, sway area and mean amplitude values for the VBF(predictive) decreased more than the same values for the VBF(real_time). The preliminary results may prove useful for the possibility of using this kind of VBF as a tool to improve postural performance.
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21
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Kilby MC, Molenaar PCM, Slobounov SM, Newell KM. Real-time visual feedback of COM and COP motion properties differentially modifies postural control structures. Exp Brain Res 2016; 235:109-120. [PMID: 27644409 DOI: 10.1007/s00221-016-4769-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Accepted: 08/30/2016] [Indexed: 11/26/2022]
Abstract
The experiment was setup to investigate the control of human quiet standing through the manipulation of augmented visual information feedback of selective properties of the motion of two primary variables in postural control: center of pressure (COP) and center of mass (COM). Five properties of feedback information were contrasted to a no feedback dual-task (watching a movie) control condition to determine the impact of visual real-time feedback on the coordination of the joint motions in postural control in both static and dynamic one-leg standing postures. The feedback information included 2D COP or COM position and macro variables derived from the COP and COM motions, namely virtual time-to-contact (VTC) and the COP-COM coupling. The findings in the static condition showed that the VTC and COP-COM coupling feedback conditions decreased postural motion more than the 2D COP or COM positional information. These variables also induced larger sway amplitudes in the dynamic condition showing a more progressive search strategy in exploring the stability limits. Canonical correlation analysis (CCA) found that COP-COM coupling contributed less than the other feedback variables to the redundancy of the system reflected in the common variance between joint motions and properties of sway motion. The COP-COM coupling had the lowest weighting of the motion properties to redundancy under the feedback conditions but overall the qualitative pattern of the joint motion structures was preserved within the respective static and dynamic balance conditions.
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Affiliation(s)
- Melissa C Kilby
- Department of Kinesiology, The University of Georgia, 330 River Rd, Athens, GA, 30602, USA.
| | - Peter C M Molenaar
- Department of Human Development and Family Studies, The Pennsylvania State University, 315 Health and Human Development East, University Park, PA, 16802, USA
| | - Semyon M Slobounov
- Department of Kinesiology, The Pennsylvania State University, 276 Recreation Building, University Park, PA, 16802, USA
| | - Karl M Newell
- Department of Kinesiology, The University of Georgia, 330 River Rd, Athens, GA, 30602, USA
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22
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dos Anjos F, Lemos T, Imbiriba LA. Does the type of visual feedback information change the control of standing balance? Eur J Appl Physiol 2016; 116:1771-9. [DOI: 10.1007/s00421-016-3434-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2016] [Accepted: 07/12/2016] [Indexed: 11/25/2022]
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Kilby MC, Slobounov SM, Newell KM. Augmented feedback of COM and COP modulates the regulation of quiet human standing relative to the stability boundary. Gait Posture 2016; 47:18-23. [PMID: 27264397 DOI: 10.1016/j.gaitpost.2016.03.021] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Revised: 03/22/2016] [Accepted: 03/31/2016] [Indexed: 02/02/2023]
Abstract
The experiment manipulated real-time kinematic feedback of the motion of the whole body center of mass (COM) and center of pressure (COP) in anterior-posterior (AP) and medial-lateral (ML) directions to investigate the variables actively controlled in quiet standing of young adults. The feedback reflected the current 2D postural positions within the 2D functional stability boundary that was scaled to 75%, 30% and 12% of its original size. The findings showed that the distance of both COP and COM to the respective stability boundary was greater during the feedback trials compared to a no feedback condition. However, the temporal safety margin of the COP, that is, the virtual time-to-contact (VTC), was higher without feedback. The coupling relation of COP-COM showed stable in-phase synchronization over all of the feedback conditions for frequencies below 1Hz. For higher frequencies (up to 5Hz), there was progressive reduction of COP-COM synchronization and local adaptation under the presence of augmented feedback. The findings show that the augmented feedback of COM and COP motion differentially and adaptively influences spatial and temporal properties of postural motion relative to the stability boundary while preserving the organization of the COM-COP coupling in postural control.
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Affiliation(s)
- Melissa C Kilby
- Department of Kinesiology, The University of Georgia, 330 River Rd, Athens, GA 30602, United States.
| | - Semyon M Slobounov
- Department of Kinesiology, The Pennsylvania State University, 276 Recreation Building, University Park, PA 16802, United States.
| | - Karl M Newell
- Department of Kinesiology, The University of Georgia, 330 River Rd, Athens, GA 30602, United States.
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24
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Donath L, Kurz E, Roth R, Zahner L, Faude O. Leg and trunk muscle coordination and postural sway during increasingly difficult standing balance tasks in young and older adults. Maturitas 2016; 91:60-8. [PMID: 27451322 DOI: 10.1016/j.maturitas.2016.05.010] [Citation(s) in RCA: 69] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Revised: 05/12/2016] [Accepted: 05/18/2016] [Indexed: 11/25/2022]
Abstract
Ageing impairs body balance and increases older adults' fall risk. Balance training can improve intrinsic fall risk factors. However, age comparisons of muscle activity responses during balance tasks are lacking. This study investigated relative muscle activity, muscle coordination and postural sway during various recommended static balance training tasks. Muscle activity (%MVC), amplitude ratios (AR) and co-activity (CAI) were determined during standing tasks for 30s (1: double limb stance on a foam surface, eyes open; 2: double limb stance on firm ground, eyes closed; 3: double limb stance, feet in step position on a foam surface, eyes open; 4: double limb stance, feet in step position on firm ground, eyes closed; 5: single limb stance on firm ground, eyes open) in 20 healthy young adults (24±2 y) and 20 older adults (73±6 y). Surface electromyography (SEMG) was applied (SENIAM guidelines) to ankle (tibialis anterior, soleus, medial gastrocnemius, peroneus longus) and thigh (vastus lateralis, vastus medialis, biceps femoris, semitendinosus) muscles (non-dominant leg). Electrodes over trunk (multifidus and internal oblique) muscles were applied bilaterally. Two- to six-fold higher levels of relative muscle activity were found in older adults for ankle (0.0002<p<0.001), thigh (0.0008<p<0.075) and trunk (0.001<p<0.036) muscles. Co-activation was elevated in young adults for the trunk (0.001<p<0.031) and in older adults for the ankle (0.009<p<0.03). Age-group differences were observed for muscle coordination patterns during all stance conditions at the ankle (0.06<ηp(2)<0.28) and the trunk (0.14<ηp(2)<0.23). Older adults had higher electrophysiological costs for all stance conditions. Muscle coordination showed inverse activity patterns at the ankle and trunk. Optimal balance and strength training programs should take into account age-specific alterations in muscle activity.
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Affiliation(s)
- Lars Donath
- University of Basel, Department of Sport, Exercise and Health, Basel, Switzerland.
| | - Eduard Kurz
- University of Basel, Department of Sport, Exercise and Health, Basel, Switzerland
| | - Ralf Roth
- University of Basel, Department of Sport, Exercise and Health, Basel, Switzerland
| | - Lukas Zahner
- University of Basel, Department of Sport, Exercise and Health, Basel, Switzerland
| | - Oliver Faude
- University of Basel, Department of Sport, Exercise and Health, Basel, Switzerland
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25
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Toumi A, Jakobi JM, Simoneau-Buessinger E. Differential impact of visual feedback on plantar- and dorsi-flexion maximal torque output. Appl Physiol Nutr Metab 2016; 41:557-9. [PMID: 27031663 DOI: 10.1139/apnm-2015-0639] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The effect of visual feedback on enhancing isometric maximal voluntary contractions (MVC) was evaluated. Twelve adults performed plantar-flexion and dorsi-flexion MVCs in 3 conditions (no visual feedback, visual feedback, and visual feedback with target). There was no significant effect of visual conditions on dorsi-flexion MVC but there was an effect on plantar-flexion. Irrespective of whether a target was evident, visual feedback increased plantar-flexion MVC by ∼15%. This study highlights the importance of optimal feedback to enhance MVC.
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Affiliation(s)
- Anis Toumi
- a Laboratoire d'Automatique, de Mécanique, et d'Informatique industrielles et Humaines (LAMIH) - UMR CNRS 8201, Université de Valenciennes et du Hainaut-Cambrésis (UVHC), F-59313 Valenciennes, France
| | - Jennifer M Jakobi
- b School of Health and Exercise Sciences, University of British Columbia Okanagan, Kelowna, BC V1V 1V7, Canada
| | - Emilie Simoneau-Buessinger
- a Laboratoire d'Automatique, de Mécanique, et d'Informatique industrielles et Humaines (LAMIH) - UMR CNRS 8201, Université de Valenciennes et du Hainaut-Cambrésis (UVHC), F-59313 Valenciennes, France
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Jehu DA, Thibault J, Lajoie Y. Magnifying the Scale of Visual Biofeedback Improves Posture. Appl Psychophysiol Biofeedback 2015; 41:151-5. [DOI: 10.1007/s10484-015-9324-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Yeh TT, Cinelli ME, Lyons JL, Lee TD. Age-related changes in postural control to the demands of a precision task. Hum Mov Sci 2015; 44:134-42. [DOI: 10.1016/j.humov.2015.08.021] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2015] [Revised: 05/08/2015] [Accepted: 08/27/2015] [Indexed: 11/16/2022]
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Multi-joint postural behavior in patients with knee osteoarthritis. Knee 2015; 22:517-21. [PMID: 26188927 DOI: 10.1016/j.knee.2014.09.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2013] [Revised: 08/28/2014] [Accepted: 09/01/2014] [Indexed: 02/02/2023]
Abstract
BACKGROUND Previous studies have demonstrated balance impairment in patients with knee osteoarthritis (OA). Although it is currently accepted that postural control depends on multi-joint coordination, no study has previously considered this postural strategy in patients suffering from knee OA. The objectives of this study were to investigate the multi-joint postural behavior in patients with knee OA and to evaluate the association with clinical outcomes. METHODS Eighty-seven patients with knee OA and twenty-five healthy elderly were recruited to the study. A motion analysis system and two force plates were used to investigate the joint kinematics (trunk and lower body segments), the lower body joint moments, the vertical ground reaction force ratio and the center of pressure (COP) during a quiet standing task. Pain, functional capacity and quality of life status were also recorded. RESULTS Patients with symptomatic and severe knee OA adopt a more flexed posture at all joint levels in comparison with the control group. A significant difference in the mean ratio was found between groups, showing an asymmetric weight distribution in patients with knee OA. A significant decrease in the COP range in the anterior-posterior direction was also observed in the group of patients. Only small associations were observed between postural impairments and clinical outcomes. CONCLUSION This study brings new insights regarding the postural behavior of patients with severe knee OA during a quiet standing task. The results confirm the multi-joint asymmetric posture adopted by this population.
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Kuznetsov NA, Riley MA. The role of task constraints in relating laboratory and clinical measures of balance. Gait Posture 2015; 42:275-9. [PMID: 26112778 DOI: 10.1016/j.gaitpost.2015.05.022] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Revised: 05/09/2015] [Accepted: 05/28/2015] [Indexed: 02/02/2023]
Abstract
This study tested the hypothesis that age-related postural control deficits are more clearly detected from force plate recordings when using postural control tasks with an explicitly defined goal as opposed to the frequently used quiet stance task. Eighteen older adults (over 65) and seventeen younger adults (under 30) stood on a force plate with visual feedback (VFB) of the center of pressure (COP) and without such visual feedback with eyes open (NVFB). In the VFB condition, online visual feedback about the COP was provided and participants maintained that feedback on a stationary visual target for 80s. We hypothesized that age-related difference in COP variability (standard deviation of COP position and average absolute maximum COP velocity; AAMV) would be more pronounced in the VFB than in the NVFB condition. In addition, we hypothesized that Berg balance scale (BBS) scores for older adults would correlate more strongly with the COP measures in the VFB condition than in the NVFB condition. Results showed that VFB enhanced age-related differences only for AAMV in anterior-posterior direction. Both age groups decreased postural sway when using VFB. Older adults increased AAMV with VFB while young adults did not, indicating that the task modified their postural control strategy stronger than in younger adults. BBS scores were correlated with the AAMV in both feedback conditions, while COP position variability was more clearly correlated with BBS in the VFB condition. These results suggest that the quiet stance task is sufficient to index balance function if velocity-based COP variables are utilized in the analysis.
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Affiliation(s)
| | - Michael A Riley
- Department of Psychology, University of Cincinnati, Cincinnati, OH USA; Center for Cognition, Action, & Perception, University of Cincinnati, Cincinnati, OH USA
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D’Anna C, Schmid M, Bibbo D, Bertollo M, Comani S, Conforto S. The Effect of Continuous and Discretized Presentations of Concurrent Augmented Visual Biofeedback on Postural Control in Quiet Stance. PLoS One 2015. [PMID: 26196518 PMCID: PMC4509646 DOI: 10.1371/journal.pone.0132711] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The purpose of this study was to evaluate the effect of a continuous and a discretized Visual Biofeedback (VBF) on balance performance in upright stance. The coordinates of the Centre of Pressure (CoP), extracted from a force plate, were processed in real-time to implement the two VBFs, administered to two groups of 12 healthy participants. In the first group, a representation of the CoP was continuously shown, while in the second group, the discretized VBF was provided at an irregular frequency (that depended on the subject's performance) by displaying one out of a set of five different emoticons, each corresponding to a specific area covered by the current position of the CoP. In the first case, participants were asked to maintain a white spot within a given square area, whereas in the second case they were asked to keep the smiling emoticon on. Trials with no VBF were administered as control. The effect of the two VBFs on balance was studied through classical postural parameters and a subset of stabilogram diffusion coefficients. To quantify the amount of time spent in stable conditions, the percentage of time during which the CoP was inside the stability area was calculated. Both VBFs improved balance maintainance as compared to the absence of any VBF. As compared to the continuous VBF, in the discretized VBF a significant decrease of sway path, diffusion and Hurst coefficients was found. These results seem to indicate that a discretized VBF favours a more natural postural behaviour by promoting a natural intermittent postural control strategy.
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Affiliation(s)
- Carmen D’Anna
- Department of Engineering, Roma Tre University, Rome, Italy
- Behavioral Imaging and Neural Dynamics Center BIND - “G. d'Annunzio” University, Chieti, Italy
- * E-mail:
| | - Maurizio Schmid
- Department of Engineering, Roma Tre University, Rome, Italy
- Behavioral Imaging and Neural Dynamics Center BIND - “G. d'Annunzio” University, Chieti, Italy
| | - Daniele Bibbo
- Department of Engineering, Roma Tre University, Rome, Italy
- Behavioral Imaging and Neural Dynamics Center BIND - “G. d'Annunzio” University, Chieti, Italy
| | - Maurizio Bertollo
- Department of Basic and Applied Medical Sciences, University “G. D’Annunzio”, Chieti, Italy
- Behavioral Imaging and Neural Dynamics Center BIND - “G. d'Annunzio” University, Chieti, Italy
| | - Silvia Comani
- Department of Neuroscience and Imaging, “G. d'Annunzio” University, Chieti, Italy
- Behavioral Imaging and Neural Dynamics Center BIND - “G. d'Annunzio” University, Chieti, Italy
| | - Silvia Conforto
- Department of Engineering, Roma Tre University, Rome, Italy
- Behavioral Imaging and Neural Dynamics Center BIND - “G. d'Annunzio” University, Chieti, Italy
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Donath L, Kurz E, Roth R, Zahner L, Faude O. Different ankle muscle coordination patterns and co-activation during quiet stance between young adults and seniors do not change after a bout of high intensity training. BMC Geriatr 2015; 15:19. [PMID: 25888336 PMCID: PMC4409995 DOI: 10.1186/s12877-015-0017-0] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Accepted: 02/17/2015] [Indexed: 11/13/2022] Open
Abstract
Background Available evidence suggests that young adults and seniors use different strategies to adjust for increasing body sway during quiet standing. Altered antagonist muscle co-activation and different ankle muscle coordination patterns may account for this finding. Consequently, we aimed at addressing whether aging leads to changes in neuromuscular coordination patterns as well as co-activation during quiet stance. We additionally investigated whether a bout of high intensity interval training additionally alters these patterns. Methods Twenty healthy seniors (age: 70 ± 4 y) and twenty young adults (age: 27 ± 3 y) were enrolled in the present study. In between the testing procedures, four consecutive high-intensity intervals of 4 min duration at a target exercise intensity of 90 to 95% HRmax were completed on a treadmill. The total center of pressure (COP) path length displacement served as standing balance performance outcome. In order to assess ankle muscle coordination patterns, amplitude ratios (AR) were calculated for each muscle (e.g. tibialis anterior (TA) [%] = (TA × 100)/(gastrocnemius medialis (GM) + soleus (SOL) + peroneus longus (PL) + TA). The co-activation was calculated for the SOL and TA muscles computing the co-activation index (CAI = 2 × TA/TA + SOL). Results Seniors showed an inverted ankle muscle coordination pattern during single limb stance with eyes open (SLEO), compared to young adults (rest: GM, S: 15 ± 8% vs Y: 24 ± 9%; p = 0.03; SOL, S: 27 ± 14% vs Y: 37 ± 18%; p = 0.009; TA, S: 31 ± 13% vs Y: 13 ± 7%; p = 0.003). These patterns did not change after a high-intensity training session. A moderate correlation between amplitude ratios of the TA-contribution and postural sway was observed for seniors during SLEO (r = 0.61). Ankle co-activation was twofold elevated in seniors compared to young adults during SLEO (p < 0.001). These findings were also not affected by high intensity training. Conclusion Increased ankle co-activation in the anterior-posterior plane and inverted ankle muscle coordination pattern merely occurred during single-leg stance. Seniors with decreased postural control showed higher TA contributions during SLEO. These neuromuscular changes are not affected by acute intermittent high intensity aerobic exercise.
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Affiliation(s)
- Lars Donath
- Department of Sport, Exercise and Health, University of Basel, Birsstrasse 320-B, 4052, Basel, Switzerland.
| | - Eduard Kurz
- Department of Sport, Exercise and Health, University of Basel, Birsstrasse 320-B, 4052, Basel, Switzerland. .,Clinic for Trauma, Hand and Reconstructive Surgery, Division of Motor Research, Pathophysiology and Biomechanics, Jena University Hospital, Bachstrasse 18, 07743, Jena, Germany.
| | - Ralf Roth
- Department of Sport, Exercise and Health, University of Basel, Birsstrasse 320-B, 4052, Basel, Switzerland.
| | - Lukas Zahner
- Department of Sport, Exercise and Health, University of Basel, Birsstrasse 320-B, 4052, Basel, Switzerland.
| | - Oliver Faude
- Department of Sport, Exercise and Health, University of Basel, Birsstrasse 320-B, 4052, Basel, Switzerland.
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Yeh TT, Cluff T, Balasubramaniam R. Visual reliance for balance control in older adults persists when visual information is disrupted by artificial feedback delays. PLoS One 2014; 9:e91554. [PMID: 24614576 PMCID: PMC3948884 DOI: 10.1371/journal.pone.0091554] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Accepted: 02/12/2014] [Indexed: 11/30/2022] Open
Abstract
Sensory information from our eyes, skin and muscles helps guide and correct balance. Less appreciated, however, is that delays in the transmission of sensory information between our eyes, limbs and central nervous system can exceed several 10s of milliseconds. Investigating how these time-delayed sensory signals influence balance control is central to understanding the postural system. Here, we investigate how delayed visual feedback and cognitive performance influence postural control in healthy young and older adults. The task required that participants position their center of pressure (COP) in a fixed target as accurately as possible without visual feedback about their COP location (eyes-open balance), or with artificial time delays imposed on visual COP feedback. On selected trials, the participants also performed a silent arithmetic task (cognitive dual task). We separated COP time series into distinct frequency components using low and high-pass filtering routines. Visual feedback delays affected low frequency postural corrections in young and older adults, with larger increases in postural sway noted for the group of older adults. In comparison, cognitive performance reduced the variability of rapid center of pressure displacements in young adults, but did not alter postural sway in the group of older adults. Our results demonstrate that older adults prioritize vision to control posture. This visual reliance persists even when feedback about the task is delayed by several hundreds of milliseconds.
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Affiliation(s)
- Ting Ting Yeh
- Sensorimotor Neuroscience Laboratory, Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada
- * E-mail:
| | - Tyler Cluff
- Sensorimotor Neuroscience Laboratory, Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada
- Laboratory of Integrative Motor Behaviour (LIMB), Centre for Neuroscience Studies, Queen's University, Kingston, Ontario, Canada
| | - Ramesh Balasubramaniam
- Sensorimotor Neuroscience Laboratory, Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada
- Cognitive and Information Sciences, University of California Merced, Merced, California, United States of America
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Use of motor abundance in old adults in the regulation of a narrow-based stance. Eur J Appl Physiol 2013; 114:261-71. [DOI: 10.1007/s00421-013-2768-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2013] [Accepted: 10/30/2013] [Indexed: 10/26/2022]
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Effectiveness of different visual biofeedback signals for human balance improvement. Gait Posture 2013; 39:410-4. [PMID: 24001870 DOI: 10.1016/j.gaitpost.2013.08.005] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2012] [Revised: 08/05/2013] [Accepted: 08/10/2013] [Indexed: 02/02/2023]
Abstract
The aim of this study was to examine the effectiveness of visual biofeedback (VBF) signals from a force platform and accelerometer sensors placed on different body segments. The study was performed on 20 young subjects during standing on a firm and foam support surface with a VBF signal sensed from CoP, lower trunk (L5) and upper trunk (Th4). The VBF signal was controlled by 2D-movement of chosen body segment, which was presented as a red point on a monitor screen. Location of VBF signal had a significant effect on each postural parameter of CoP and trunk segments. RMS and amplitudes of postural sway in medial-lateral and anterior-posterior directions decreased during standing on both types of support surface due to VBF. L5-VBF and CoP-VBF significantly reduced CoP displacements and lower trunk tilts. Th4-VBF reduced upper trunk tilts. Frequency analysis of postural sway revealed a decrease of power spectral density (PSD) values in low frequency range (0.02-0.3Hz) and an increase of PSD values in higher frequency range (0.5-1.4 Hz) in the VBF conditions during the stance on the firm surface in anterior-posterior direction. Reduction of body sway was the most significant in the body segment from which the VBF signal was sensed. The CoP position and L5 position provided the best signals for VBF. Changes in frequency ranges of body sway suggest voluntary activation of balance control. The results open new opportunities to optimize VBF system for balance improvement using accelerometers.
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