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Cai L, Yan S, Ouyang C, Zhang T, Zhu J, Chen L, Ma X, Liu H. Muscle synergies in joystick manipulation. Front Physiol 2023; 14:1282295. [PMID: 37900948 PMCID: PMC10611508 DOI: 10.3389/fphys.2023.1282295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Accepted: 09/27/2023] [Indexed: 10/31/2023] Open
Abstract
Extracting muscle synergies from surface electromyographic signals (sEMGs) during exercises has been widely applied to evaluate motor control strategies. This study explores the relationship between upper-limb muscle synergies and the performance of joystick manipulation tasks. Seventy-seven subjects, divided into three classes according to their maneuvering experience, were recruited to perform the left and right reciprocation of the joystick. Based on the motion encoder data, their manipulation performance was evaluated by the mean error, standard deviation, and extreme range of position of the joystick. Meanwhile, sEMG and acceleration signals from the upper limbs corresponding to the entire trial were collected. Muscle synergies were extracted from each subject's sEMG data by non-negative matrix factorization (NMF), based on which the synergy coordination index (SCI), which indicates the size of the synergy space and the variability of the center of activity (CoA), evaluated the temporal activation variability. The synergy pattern space and CoA of all participants were calculated within each class to analyze the correlation between the variability of muscle synergies and the manipulation performance metrics. The correlation level of each class was further compared. The experimental results evidenced a positive correlation between manipulation performance and maneuvering experience. Similar muscle synergy patterns were reflected between the three classes and the structure of the muscle synergies showed stability. In the class of rich maneuvering experience, the correlation between manipulation performance metrics and muscle synergy is more significant than in the classes of trainees and newbies, suggesting that long-term training and practicing can improve manipulation performance, stability of synergy compositions, and temporal activation variability but not alter the structure of muscle synergies determined by a specific task. Our approaches and findings could be applied to 1) reduce manipulation errors, 2) assist maneuvering training and evaluation to enhance transportation safety, and 3) design technical support for sports.
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Affiliation(s)
- Liming Cai
- Academy for Engineering and Technology, Fudan University, Shanghai, China
- Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou, China
| | - Shuhao Yan
- Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou, China
- School of Biomedical Engineering (Suzhou), Division of Life Sciences and Medicine University of Science and Technology of China, Suzhou, China
| | - Chuanyun Ouyang
- Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou, China
- School of Biomedical Engineering (Suzhou), Division of Life Sciences and Medicine University of Science and Technology of China, Suzhou, China
| | - Tianxiang Zhang
- Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou, China
- School of Biomedical Engineering (Suzhou), Division of Life Sciences and Medicine University of Science and Technology of China, Suzhou, China
| | - Jun Zhu
- Academy for Engineering and Technology, Fudan University, Shanghai, China
| | - Li Chen
- Academy for Engineering and Technology, Fudan University, Shanghai, China
- Department of Orthopedics, Huashan Hospital, Fudan University, Shanghai, China
| | - Xin Ma
- Academy for Engineering and Technology, Fudan University, Shanghai, China
- Department of Orthopedics, Huashan Hospital, Fudan University, Shanghai, China
| | - Hui Liu
- Cognitive Systems Lab, University of Bremen, Bremen, Germany
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2
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Bach MM, Zandvoort CS, Cappellini G, Ivanenko Y, Lacquaniti F, Daffertshofer A, Dominici N. Development of running is not related to time since onset of independent walking, a longitudinal case study. Front Hum Neurosci 2023; 17:1101432. [PMID: 36875237 PMCID: PMC9978154 DOI: 10.3389/fnhum.2023.1101432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Accepted: 01/23/2023] [Indexed: 02/18/2023] Open
Abstract
Introduction Children start to run after they master walking. How running develops, however, is largely unknown. Methods We assessed the maturity of running pattern in two very young, typically developing children in a longitudinal design spanning about three years. Leg and trunk 3D kinematics and electromyography collected in six recording sessions, with more than a hundred strides each, entered our analysis. We recorded walking during the first session (the session of the first independent steps of the two toddlers at the age of 11.9 and 10.6 months) and fast walking or running for the subsequent sessions. More than 100 kinematic and neuromuscular parameters were determined for each session and stride. The equivalent data of five young adults served to define mature running. After dimensionality reduction using principal component analysis, hierarchical cluster analysis based on the average pairwise correlation distance to the adult running cluster served as a measure for maturity of the running pattern. Results Both children developed running. Yet, in one of them the running pattern did not reach maturity whereas in the other it did. As expected, mature running appeared in later sessions (>13 months after the onset of independent walking). Interestingly, mature running alternated with episodes of immature running within sessions. Our clustering approach separated them. Discussion An additional analysis of the accompanying muscle synergies revealed that the participant who did not reach mature running had more differences in muscle contraction when compared to adults than the other. One may speculate that this difference in muscle activity may have caused the difference in running pattern.
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Affiliation(s)
- Margit M. Bach
- Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Amsterdam Movement Sciences & Institute of Brain and Behavior Amsterdam, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Coen S. Zandvoort
- Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Amsterdam Movement Sciences & Institute of Brain and Behavior Amsterdam, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Germana Cappellini
- Laboratory of Neuromotor Physiology, Istituto di Ricovero e Cura a Carattere Scientifico Fondazione Santa Lucia, Rome, Italy
- Department of Systems Medicine, Center of Space Biomedicine, University of Rome Tor Vergata, Rome, Italy
| | - Yury Ivanenko
- Laboratory of Neuromotor Physiology, Istituto di Ricovero e Cura a Carattere Scientifico Fondazione Santa Lucia, Rome, Italy
| | - Francesco Lacquaniti
- Laboratory of Neuromotor Physiology, Istituto di Ricovero e Cura a Carattere Scientifico Fondazione Santa Lucia, Rome, Italy
- Department of Systems Medicine, Center of Space Biomedicine, University of Rome Tor Vergata, Rome, Italy
| | - Andreas Daffertshofer
- Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Amsterdam Movement Sciences & Institute of Brain and Behavior Amsterdam, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Nadia Dominici
- Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Amsterdam Movement Sciences & Institute of Brain and Behavior Amsterdam, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
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3
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Zhvansky DS, Sylos-Labini F, Dewolf A, Cappellini G, d’Avella A, Lacquaniti F, Ivanenko Y. Evaluation of Spatiotemporal Patterns of the Spinal Muscle Coordination Output during Walking in the Exoskeleton. SENSORS (BASEL, SWITZERLAND) 2022; 22:s22155708. [PMID: 35957264 PMCID: PMC9370895 DOI: 10.3390/s22155708] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2022] [Revised: 07/21/2022] [Accepted: 07/26/2022] [Indexed: 06/01/2023]
Abstract
Recent advances in the performance and evaluation of walking in exoskeletons use various assessments based on kinematic/kinetic measurements. While such variables provide general characteristics of gait performance, only limited conclusions can be made about the neural control strategies. Moreover, some kinematic or kinetic parameters are a consequence of the control implemented on the exoskeleton. Therefore, standard indicators based on kinematic variables have limitations and need to be complemented by performance measures of muscle coordination and control strategy. Knowledge about what happens at the spinal cord output level might also be critical for rehabilitation since an abnormal spatiotemporal integration of activity in specific spinal segments may result in a risk for abnormalities in gait recovery. Here we present the PEPATO software, which is a benchmarking solution to assess changes in the spinal locomotor output during walking in the exoskeleton with respect to reference data on normal walking. In particular, functional and structural changes at the spinal cord level can be mapped into muscle synergies and spinal maps of motoneuron activity. A user-friendly software interface guides the user through several data processing steps leading to a set of performance indicators as output. We present an example of the usage of this software for evaluating walking in an unloading exoskeleton that allows a person to step in simulated reduced (the Moon's) gravity. By analyzing the EMG activity from lower limb muscles, the algorithms detected several performance indicators demonstrating differential adaptation (shifts in the center of activity, prolonged activation) of specific muscle activation modules and spinal motor pools and increased coactivation of lumbar and sacral segments. The software is integrated at EUROBENCH facilities to benchmark the performance of walking in the exoskeleton from the point of view of changes in the spinal locomotor output.
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Affiliation(s)
- Dmitry S. Zhvansky
- Institute for Information Transmission Problems, Russian Academy of Sciences, 127994 Moscow, Russia;
| | - Francesca Sylos-Labini
- Laboratory of Neuromotor Physiology, IRCCS Santa Lucia Foundation, 00179 Rome, Italy; (F.S.-L.); (A.D.); (G.C.); (A.d.); (F.L.)
- Department of Systems Medicine, University of Rome Tor Vergata, 00133 Rome, Italy
| | - Arthur Dewolf
- Laboratory of Neuromotor Physiology, IRCCS Santa Lucia Foundation, 00179 Rome, Italy; (F.S.-L.); (A.D.); (G.C.); (A.d.); (F.L.)
- Department of Systems Medicine, University of Rome Tor Vergata, 00133 Rome, Italy
| | - Germana Cappellini
- Laboratory of Neuromotor Physiology, IRCCS Santa Lucia Foundation, 00179 Rome, Italy; (F.S.-L.); (A.D.); (G.C.); (A.d.); (F.L.)
- Department of Systems Medicine, University of Rome Tor Vergata, 00133 Rome, Italy
| | - Andrea d’Avella
- Laboratory of Neuromotor Physiology, IRCCS Santa Lucia Foundation, 00179 Rome, Italy; (F.S.-L.); (A.D.); (G.C.); (A.d.); (F.L.)
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, University of Messina, 98100 Messina, Italy
| | - Francesco Lacquaniti
- Laboratory of Neuromotor Physiology, IRCCS Santa Lucia Foundation, 00179 Rome, Italy; (F.S.-L.); (A.D.); (G.C.); (A.d.); (F.L.)
- Department of Systems Medicine and Center of Space Biomedicine, University of Rome Tor Vergata, 00133 Rome, Italy
| | - Yury Ivanenko
- Laboratory of Neuromotor Physiology, IRCCS Santa Lucia Foundation, 00179 Rome, Italy; (F.S.-L.); (A.D.); (G.C.); (A.d.); (F.L.)
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4
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Hagio S, Ishihara A, Terada M, Tanabe H, Kibushi B, Higashibata A, Yamada S, Furukawa S, Mukai C, Ishioka N, Kouzaki M. Muscle synergies of multi-directional postural control in astronauts on Earth after a long-term stay in space. J Neurophysiol 2022; 127:1230-1239. [PMID: 35353615 DOI: 10.1152/jn.00232.2021] [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: 11/22/2022] Open
Abstract
Movements of the human biological system have adapted to the physical environment under the 1-g gravitational force on Earth. However, the effects of microgravity in space on the underlying functional neuromuscular control behaviors remain poorly understood. Here, we aimed to elucidate the effects of prolonged exposure to a microgravity environment on the functional coordination of multiple muscle activities. The activities of 16 lower limb muscles of 5 astronauts who stayed in space for at least 3 months were recorded while they maintained multidirectional postural control during bipedal standing. The coordinated activation patterns of groups of muscles, i.e., muscle synergies, were estimated from the muscle activation datasets using a factorization algorithm. The experiments were repeated a total of 5 times for each astronaut, once before and 4 times after spaceflight. The compositions of muscle synergies were altered, with a constant number of synergies, after long-term exposure to microgravity, and the extent of the changes was correlated with the severity of the deficits in postural stability. Furthermore, the muscle synergies extracted 3 months after the return were similar in their activation profile but not in their muscle composition compared with those extracted in the preflight condition. These results suggest that the modularity in the neuromuscular system became reorganized to adapt to the microgravity environment and then possibly reoptimized to the new sensorimotor environment after the astronauts were re-exposed to a gravitational force. It is expected that muscle synergies can be used as physiological markers of the status of astronauts with gravity-dependent change.
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Affiliation(s)
- Shota Hagio
- Laboratory of Neurophysiology, Graduate School of Human and Environmental Studies, Kyoto University, Kyoto, Japan.,Unit of Synergetic Studies for Space, Kyoto University, Kyoto, Japan
| | - Akihiko Ishihara
- Laboratory of Cell Biology and Life Science, Graduate School of Human and Environmental Studies, Kyoto University, Kyoto, Japan
| | - Masahiro Terada
- Unit of Synergetic Studies for Space, Kyoto University, Kyoto, Japan
| | - Hiroko Tanabe
- Institutes of Innovation for Future Society, Nagoya University, Aichi, Japan
| | - Benio Kibushi
- Faculty of Sport Science, Waseda University, Saitama, Japan
| | - Akira Higashibata
- Human Spaceflight Technology Directorate, Japan Aerospace Exploration Agency, Ibaraki, Japan
| | - Shin Yamada
- Graduate School of Medicine, Kyorin University, Tokyo, Japan
| | - Satoshi Furukawa
- Human Spaceflight Technology Directorate, Japan Aerospace Exploration Agency, Ibaraki, Japan
| | - Chiaki Mukai
- Human Spaceflight Technology Directorate, Japan Aerospace Exploration Agency, Ibaraki, Japan
| | - Noriaki Ishioka
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Kanagawa, Japan
| | - Motoki Kouzaki
- Laboratory of Neurophysiology, Graduate School of Human and Environmental Studies, Kyoto University, Kyoto, Japan.,Unit of Synergetic Studies for Space, Kyoto University, Kyoto, Japan
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5
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Kerkman JN, Zandvoort CS, Daffertshofer A, Dominici N. Body Weight Control Is a Key Element of Motor Control for Toddlers' Walking. FRONTIERS IN NETWORK PHYSIOLOGY 2022; 2:844607. [PMID: 36926099 PMCID: PMC10013000 DOI: 10.3389/fnetp.2022.844607] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Accepted: 02/10/2022] [Indexed: 01/21/2023]
Abstract
New-borns can step when supported for about 70-80% of their own body weight. Gravity-related sensorimotor information might be an important factor in developing the ability to walk independently. We explored how body weight support alters motor control in toddlers during the first independent steps and in toddlers with about half a year of walking experience. Sixteen different typically developing children were assessed during (un)supported walking on a running treadmill. Electromyography of 18-24 bilateral leg and back muscles and vertical ground reaction forces were recorded. Strides were grouped into four levels of body weight support ranging from no (<10%), low (10-35%), medium (35-55%), and high (55-95%) support. We constructed muscle synergies and muscle networks and assessed differences between levels of support and between groups. In both groups, muscle activities could be described by four synergies. As expected, the mean activity decreased with body weight support around foot strikes. The younger first-steps group showed changes in the temporal pattern of the synergies when supported for more than 35% of their body weight. In this group, the muscle network was dense with several interlimb connections. Apparently, the ability to process gravity-related information is not fully developed at the onset of independent walking causing motor control to be fairly disperse. Synergy-specific sensitivity for unloading implies distinct neural mechanisms underlying (the emergence of) these synergies.
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Affiliation(s)
- Jennifer N Kerkman
- Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Amsterdam Movement Science Institute (AMS) and Institute for Brain and Behaviour Amsterdam (iBBA), Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Coen S Zandvoort
- Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Amsterdam Movement Science Institute (AMS) and Institute for Brain and Behaviour Amsterdam (iBBA), Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Andreas Daffertshofer
- Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Amsterdam Movement Science Institute (AMS) and Institute for Brain and Behaviour Amsterdam (iBBA), Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Nadia Dominici
- Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Amsterdam Movement Science Institute (AMS) and Institute for Brain and Behaviour Amsterdam (iBBA), Vrije Universiteit Amsterdam, Amsterdam, Netherlands
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6
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Gastrocnemius medialis contractile behavior during running differs between simulated Lunar and Martian gravities. Sci Rep 2021; 11:22555. [PMID: 34799596 PMCID: PMC8604970 DOI: 10.1038/s41598-021-00527-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Accepted: 10/13/2021] [Indexed: 12/01/2022] Open
Abstract
The international partnership of space agencies has agreed to proceed forward to the Moon sustainably. Activities on the Lunar surface (0.16 g) will allow crewmembers to advance the exploration skills needed when expanding human presence to Mars (0.38 g). Whilst data from actual hypogravity activities are limited to the Apollo missions, simulation studies have indicated that ground reaction forces, mechanical work, muscle activation, and joint angles decrease with declining gravity level. However, these alterations in locomotion biomechanics do not necessarily scale to the gravity level, the reduction in gastrocnemius medialis activation even appears to level off around 0.2 g, while muscle activation pattern remains similar. Thus, it is difficult to predict whether gastrocnemius medialis contractile behavior during running on Moon will basically be the same as on Mars. Therefore, this study investigated lower limb joint kinematics and gastrocnemius medialis behavior during running at 1 g, simulated Martian gravity, and simulated Lunar gravity on the vertical treadmill facility. The results indicate that hypogravity-induced alterations in joint kinematics and contractile behavior still persist between simulated running on the Moon and Mars. This contrasts with the concept of a ceiling effect and should be carefully considered when evaluating exercise prescriptions and the transferability of locomotion practiced in Lunar gravity to Martian gravity.
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7
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Richter C, Braunstein B, Staeudle B, Attias J, Suess A, Weber T, Mileva KN, Rittweger J, Green DA, Albracht K. Contractile behavior of the gastrocnemius medialis muscle during running in simulated hypogravity. NPJ Microgravity 2021; 7:32. [PMID: 34373462 PMCID: PMC8352871 DOI: 10.1038/s41526-021-00155-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Accepted: 06/11/2021] [Indexed: 02/07/2023] Open
Abstract
Vigorous exercise countermeasures in microgravity can largely attenuate muscular degeneration, albeit the extent of applied loading is key for the extent of muscle wasting. Running on the International Space Station is usually performed with maximum loads of 70% body weight (0.7 g). However, it has not been investigated how the reduced musculoskeletal loading affects muscle and series elastic element dynamics, and thereby force and power generation. Therefore, this study examined the effects of running on the vertical treadmill facility, a ground-based analog, at simulated 0.7 g on gastrocnemius medialis contractile behavior. The results reveal that fascicle-series elastic element behavior differs between simulated hypogravity and 1 g running. Whilst shorter peak series elastic element lengths at simulated 0.7 g appear to be the result of lower muscular and gravitational forces acting on it, increased fascicle lengths and decreased velocities could not be anticipated, but may inform the development of optimized running training in hypogravity. However, whether the alterations in contractile behavior precipitate musculoskeletal degeneration warrants further study.
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Affiliation(s)
- Charlotte Richter
- Department of Medical Engineering and Technomathematics, University of Applied Sciences Aachen, Aachen, Germany.
- German Sport University Cologne, Institute of Movement and Neurosciences, Cologne, Germany.
| | - Bjoern Braunstein
- German Sport University Cologne, Institute of Movement and Neurosciences, Cologne, Germany
- German Sport University Cologne, Institute of Biomechanics and Orthopaedics, Cologne, Germany
- Centre for Health and Integrative Physiology in Space (CHIPS), Cologne, Germany
- German Research Centre of Elite Sport, Cologne, Germany
| | - Benjamin Staeudle
- Department of Medical Engineering and Technomathematics, University of Applied Sciences Aachen, Aachen, Germany
- German Sport University Cologne, Institute of Movement and Neurosciences, Cologne, Germany
| | - Julia Attias
- King's College London, Centre of Human and Applied Physiological Sciences, London, UK
| | - Alexander Suess
- European Astronaut Centre (EAC), European Space Agency, Space Medicine Team (HRE-OM), Cologne, Germany
| | - Tobias Weber
- European Astronaut Centre (EAC), European Space Agency, Space Medicine Team (HRE-OM), Cologne, Germany
- KBR GmbH, Cologne, Germany
| | - Katya N Mileva
- London South Bank University, School of Applied Sciences, London, UK
| | - Joern Rittweger
- Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany
- Department of Pediatrics and Adolescent Medicine, University of Cologne, Cologne, Germany
| | - David A Green
- King's College London, Centre of Human and Applied Physiological Sciences, London, UK
- European Astronaut Centre (EAC), European Space Agency, Space Medicine Team (HRE-OM), Cologne, Germany
- KBR GmbH, Cologne, Germany
| | - Kirsten Albracht
- Department of Medical Engineering and Technomathematics, University of Applied Sciences Aachen, Aachen, Germany
- German Sport University Cologne, Institute of Movement and Neurosciences, Cologne, Germany
- Institute for Bioengineering, University of Applied Sciences Aachen, Aachen, Germany
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8
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Hagio S, Nakazato M, Kouzaki M. Modulation of spatial and temporal modules in lower limb muscle activations during walking with simulated reduced gravity. Sci Rep 2021; 11:14749. [PMID: 34285306 PMCID: PMC8292403 DOI: 10.1038/s41598-021-94201-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 07/05/2021] [Indexed: 11/17/2022] Open
Abstract
Gravity plays a crucial role in shaping patterned locomotor output to maintain dynamic stability during locomotion. The present study aimed to clarify the gravity-dependent regulation of modules that organize multiple muscle activities during walking in humans. Participants walked on a treadmill at seven speeds (1-6 km h-1 and a subject- and gravity-specific speed determined by the Froude number (Fr) corresponding to 0.25) while their body weight was partially supported by a lift to simulate walking with five levels of gravity conditions from 0.07 to 1 g. Modules, i.e., muscle-weighting vectors (spatial modules) and phase-dependent activation coefficients (temporal modules), were extracted from 12 lower-limb electromyographic (EMG) activities in each gravity (Fr ~ 0.25) using nonnegative matrix factorization. Additionally, a tensor decomposition model was fit to the EMG data to quantify variables depending on the gravity conditions and walking speed with prescribed spatial and temporal modules. The results demonstrated that muscle activity could be explained by four modules from 1 to 0.16 g and three modules at 0.07 g, and the modules were shared for both spatial and temporal components among the gravity conditions. The task-dependent variables of the modules acting on the supporting phase linearly decreased with decreasing gravity, whereas that of the module contributing to activation prior to foot contact showed nonlinear U-shaped modulation. Moreover, the profiles of the gravity-dependent modulation changed as a function of walking speed. In conclusion, reduced gravity walking was achieved by regulating the contribution of prescribed spatial and temporal coordination in muscle activities.
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Affiliation(s)
- Shota Hagio
- Laboratory of Neurophysiology, Graduate School of Human and Environmental Studies, Kyoto University, Yoshida-nihonmatsu-cho, Sakyo-ku, Kyoto, 606-8501, Japan.
- Unit of Synergetic Studies for Space, Kyoto University, Kyoto, 606-8502, Japan.
| | - Makoto Nakazato
- Laboratory of Neurophysiology, Graduate School of Human and Environmental Studies, Kyoto University, Yoshida-nihonmatsu-cho, Sakyo-ku, Kyoto, 606-8501, Japan
| | - Motoki Kouzaki
- Laboratory of Neurophysiology, Graduate School of Human and Environmental Studies, Kyoto University, Yoshida-nihonmatsu-cho, Sakyo-ku, Kyoto, 606-8501, Japan
- Unit of Synergetic Studies for Space, Kyoto University, Kyoto, 606-8502, Japan
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9
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Richter C, Braunstein B, Staeudle B, Attias J, Suess A, Weber T, Mileva KN, Rittweger J, Green DA, Albracht K. Gastrocnemius Medialis Contractile Behavior Is Preserved During 30% Body Weight Supported Gait Training. Front Sports Act Living 2021; 2:614559. [PMID: 33537667 PMCID: PMC7849151 DOI: 10.3389/fspor.2020.614559] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Accepted: 11/23/2020] [Indexed: 11/13/2022] Open
Abstract
Rehabilitative body weight supported gait training aims at restoring walking function as a key element in activities of daily living. Studies demonstrated reductions in muscle and joint forces, while kinematic gait patterns appear to be preserved with up to 30% weight support. However, the influence of body weight support on muscle architecture, with respect to fascicle and series elastic element behavior is unknown, despite this having potential clinical implications for gait retraining. Eight males (31.9 ± 4.7 years) walked at 75% of the speed at which they typically transition to running, with 0% and 30% body weight support on a lower-body positive pressure treadmill. Gastrocnemius medialis fascicle lengths and pennation angles were measured via ultrasonography. Additionally, joint kinematics were analyzed to determine gastrocnemius medialis muscle-tendon unit lengths, consisting of the muscle's contractile and series elastic elements. Series elastic element length was assessed using a muscle-tendon unit model. Depending on whether data were normally distributed, a paired t-test or Wilcoxon signed rank test was performed to determine if body weight supported walking had any effects on joint kinematics and fascicle-series elastic element behavior. Walking with 30% body weight support had no statistically significant effect on joint kinematics and peak series elastic element length. Furthermore, at the time when peak series elastic element length was achieved, and on average across the entire stance phase, muscle-tendon unit length, fascicle length, pennation angle, and fascicle velocity were unchanged with respect to body weight support. In accordance with unchanged gait kinematics, preservation of fascicle-series elastic element behavior was observed during walking with 30% body weight support, which suggests transferability of gait patterns to subsequent unsupported walking.
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Affiliation(s)
- Charlotte Richter
- Institute of Movement and Neurosciences, German Sport University Cologne, Cologne, Germany.,Department of Medical Engineering and Technomathematics, University of Applied Sciences Aachen, Aachen, Germany
| | - Bjoern Braunstein
- Institute of Movement and Neurosciences, German Sport University Cologne, Cologne, Germany.,Institute of Biomechanics and Orthopaedics, German Sport University Cologne, Cologne, Germany.,Centre for Health and Integrative Physiology in Space (CHIPS), Cologne, Germany.,German Research Centre of Elite Sport, Cologne, Germany
| | - Benjamin Staeudle
- Institute of Movement and Neurosciences, German Sport University Cologne, Cologne, Germany.,Department of Medical Engineering and Technomathematics, University of Applied Sciences Aachen, Aachen, Germany
| | - Julia Attias
- Centre of Human and Applied Physiological Sciences, King's College London, London, United Kingdom
| | - Alexander Suess
- European Astronaut Centre (EAC), European Space Agency, Space Medicine Team (HRE-OM), Cologne, Germany
| | - Tobias Weber
- European Astronaut Centre (EAC), European Space Agency, Space Medicine Team (HRE-OM), Cologne, Germany.,KBR GmbH, Cologne, Germany
| | - Katya N Mileva
- School of Applied Sciences, London South Bank University, London, United Kingdom
| | - Joern Rittweger
- Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany.,Department of Pediatrics and Adolescent Medicine, University of Cologne, Cologne, Germany
| | - David A Green
- Centre of Human and Applied Physiological Sciences, King's College London, London, United Kingdom.,European Astronaut Centre (EAC), European Space Agency, Space Medicine Team (HRE-OM), Cologne, Germany.,KBR GmbH, Cologne, Germany
| | - Kirsten Albracht
- Institute of Movement and Neurosciences, German Sport University Cologne, Cologne, Germany.,Department of Medical Engineering and Technomathematics, University of Applied Sciences Aachen, Aachen, Germany.,Institute for Bioengineering, University of Applied Sciences Aachen, Aachen, Germany
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10
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Dewolf AH, Sylos-Labini F, Cappellini G, Lacquaniti F, Ivanenko Y. Emergence of Different Gaits in Infancy: Relationship Between Developing Neural Circuitries and Changing Biomechanics. Front Bioeng Biotechnol 2020; 8:473. [PMID: 32509753 PMCID: PMC7248179 DOI: 10.3389/fbioe.2020.00473] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Accepted: 04/23/2020] [Indexed: 12/13/2022] Open
Abstract
How does gait-specific pattern generation evolve in early infancy? The idea that neural and biomechanical mechanisms underlying mature walking and running differ to some extent and involve distinct spinal and supraspinal neural circuits is supported by various studies. Here we consider the issue of human gaits from the developmental point of view, from neonate stepping to adult mature gaits. While differentiating features of the walk and run are clearly distinct in adults, the gradual and progressive developmental bifurcation between the different gaits suggests considerable sharing of circuitry. Gaits development and their biomechanical determinants also depend on maturation of the musculoskeletal system. This review outlines the possible overlap in the neural and biomechanical control of walking and running in infancy, supporting the idea that gaits may be built starting from common, likely phylogenetically conserved elements. Bridging connections between movement mechanics and neural control of locomotion could have profound clinical implications for technological solutions to understand better locomotor development and to diagnose early motor deficits. We also consider the neuromuscular maturation time frame of gaits resulting from active practice of locomotion, underlying plasticity of development.
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Affiliation(s)
- Arthur Henri Dewolf
- Department of Systems Medicine and Center of Space Biomedicine, University of Rome Tor Vergata, Rome, Italy
| | | | - Germana Cappellini
- Laboratory of Neuromotor Physiology, IRCCS Santa Lucia Foundation, Rome, Italy.,Department of Pediatric Neurorehabilitation, IRCCS Santa Lucia Foundation, Rome, Italy
| | - Francesco Lacquaniti
- Department of Systems Medicine and Center of Space Biomedicine, University of Rome Tor Vergata, Rome, Italy.,Laboratory of Neuromotor Physiology, IRCCS Santa Lucia Foundation, Rome, Italy
| | - Yury Ivanenko
- Laboratory of Neuromotor Physiology, IRCCS Santa Lucia Foundation, Rome, Italy
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Tatarelli A, Serrao M, Varrecchia T, Fiori L, Draicchio F, Silvetti A, Conforto S, De Marchis C, Ranavolo A. Global Muscle Coactivation of the Sound Limb in Gait of People with Transfemoral and Transtibial Amputation. SENSORS 2020; 20:s20092543. [PMID: 32365715 PMCID: PMC7249183 DOI: 10.3390/s20092543] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 04/24/2020] [Accepted: 04/27/2020] [Indexed: 12/25/2022]
Abstract
The aim of this study was to analyze the effect of the level of amputation and various prosthetic devices on the muscle activation of the sound limb in people with unilateral transfemoral and transtibial amputation. We calculated the global coactivation of 12 muscles using the time-varying multimuscle coactivation function method in 37 subjects with unilateral transfemoral amputation (10, 16, and 11 with mechanical, electronic, and bionic prostheses, respectively), 11 subjects with transtibial amputation, and 22 healthy subjects representing the control group. The results highlighted that people with amputation had a global coactivation temporal profile similar to that of healthy subjects. However, amputation increased the level of the simultaneous activation of many muscles during the loading response and push-off phases of the gait cycle and decreased it in the midstance and swing subphases. This increased coactivation probably plays a role in prosthetic gait asymmetry and energy consumption. Furthermore, people with amputation and wearing electronic prosthesis showed lower global coactivation when compared with people wearing mechanical and bionic prostheses. These findings suggest that the global lower limb coactivation behavior can be a useful tool to analyze the motor control strategies adopted and the ability to adapt to the prosthetic device.
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Affiliation(s)
- Antonella Tatarelli
- Department of Human Neurosciences, University of Rome Sapienza, 00185 Rome, Italy
- Department of Occupational and Environmental Medicine, Epidemiology and Hygiene, INAIL, Monte Porzio Catone, 00185 Rome, Italy; (T.V.); (F.D.); (A.S.); (A.R.)
- Correspondence:
| | - Mariano Serrao
- Department of Medico-Surgical Sciences and Biotechnologies, University of Rome Sapienza, 04100 Latina, Italy;
| | - Tiwana Varrecchia
- Department of Occupational and Environmental Medicine, Epidemiology and Hygiene, INAIL, Monte Porzio Catone, 00185 Rome, Italy; (T.V.); (F.D.); (A.S.); (A.R.)
| | - Lorenzo Fiori
- Department of Physiology and Pharmacology, University of Rome Sapienza, 00185 Rome, Italy;
| | - Francesco Draicchio
- Department of Occupational and Environmental Medicine, Epidemiology and Hygiene, INAIL, Monte Porzio Catone, 00185 Rome, Italy; (T.V.); (F.D.); (A.S.); (A.R.)
| | - Alessio Silvetti
- Department of Occupational and Environmental Medicine, Epidemiology and Hygiene, INAIL, Monte Porzio Catone, 00185 Rome, Italy; (T.V.); (F.D.); (A.S.); (A.R.)
| | - Silvia Conforto
- Department of Engineering, Roma TRE University, 00185 Rome, Italy; (S.C.); (C.D.M.)
| | - Cristiano De Marchis
- Department of Engineering, Roma TRE University, 00185 Rome, Italy; (S.C.); (C.D.M.)
| | - Alberto Ranavolo
- Department of Occupational and Environmental Medicine, Epidemiology and Hygiene, INAIL, Monte Porzio Catone, 00185 Rome, Italy; (T.V.); (F.D.); (A.S.); (A.R.)
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12
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Aoi S, Ohashi T, Bamba R, Fujiki S, Tamura D, Funato T, Senda K, Ivanenko Y, Tsuchiya K. Neuromusculoskeletal model that walks and runs across a speed range with a few motor control parameter changes based on the muscle synergy hypothesis. Sci Rep 2019; 9:369. [PMID: 30674970 PMCID: PMC6344546 DOI: 10.1038/s41598-018-37460-3] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 12/07/2018] [Indexed: 01/14/2023] Open
Abstract
Humans walk and run, as well as change their gait speed, through the control of their complicated and redundant musculoskeletal system. These gaits exhibit different locomotor behaviors, such as a double-stance phase in walking and flight phase in running. The complex and redundant nature of the musculoskeletal system and the wide variation in locomotion characteristics lead us to imagine that the motor control strategies for these gaits, which remain unclear, are extremely complex and differ from one another. It has been previously proposed that muscle activations may be generated by linearly combining a small set of basic pulses produced by central pattern generators (muscle synergy hypothesis). This control scheme is simple and thought to be shared between walking and running at different speeds. Demonstrating that this control scheme can generate walking and running and change the speed is critical, as bipedal locomotion is dynamically challenging. Here, we provide such a demonstration by using a motor control model with 69 parameters developed based on the muscle synergy hypothesis. Specifically, we show that it produces both walking and running of a human musculoskeletal model by changing only seven key motor control parameters. Furthermore, we show that the model can walk and run at different speeds by changing only the same seven parameters based on the desired speed. These findings will improve our understanding of human motor control in locomotion and provide guiding principles for the control design of wearable exoskeletons and prostheses.
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Affiliation(s)
- Shinya Aoi
- Department of Aeronautics and Astronautics, Graduate School of Engineering, Kyoto University, Kyoto daigaku-Katsura, Nishikyo-ku, Kyoto, 615-8540, Japan.
| | - Tomohiro Ohashi
- Department of Aeronautics and Astronautics, Graduate School of Engineering, Kyoto University, Kyoto daigaku-Katsura, Nishikyo-ku, Kyoto, 615-8540, Japan
| | - Ryoko Bamba
- Department of Aeronautics and Astronautics, Graduate School of Engineering, Kyoto University, Kyoto daigaku-Katsura, Nishikyo-ku, Kyoto, 615-8540, Japan
| | - Soichiro Fujiki
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo, 153-8902, Japan
| | - Daiki Tamura
- Department of Aeronautics and Astronautics, Graduate School of Engineering, Kyoto University, Kyoto daigaku-Katsura, Nishikyo-ku, Kyoto, 615-8540, Japan
| | - Tetsuro Funato
- Department of Mechanical Engineering and Intelligent Systems, Graduate School of Informatics and Engineering, The University of Electro-Communications, 1-5-1 Choufugaoka, Choufu-shi, Tokyo, 182-8585, Japan
| | - Kei Senda
- Department of Aeronautics and Astronautics, Graduate School of Engineering, Kyoto University, Kyoto daigaku-Katsura, Nishikyo-ku, Kyoto, 615-8540, Japan
| | - Yury Ivanenko
- Laboratory of Neuromotor Physiology, IRCCS Santa Lucia Foundation, 00179, Rome, Italy
| | - Kazuo Tsuchiya
- Department of Aeronautics and Astronautics, Graduate School of Engineering, Kyoto University, Kyoto daigaku-Katsura, Nishikyo-ku, Kyoto, 615-8540, Japan
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13
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Sylos-Labini F, d'Avella A, Lacquaniti F, Ivanenko Y. Human-Human Interaction Forces and Interlimb Coordination During Side-by-Side Walking With Hand Contact. Front Physiol 2018; 9:179. [PMID: 29563883 PMCID: PMC5850283 DOI: 10.3389/fphys.2018.00179] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Accepted: 02/20/2018] [Indexed: 01/03/2023] Open
Abstract
Handholding can naturally occur between two walkers. When people walk side-by-side, either with or without hand contact, they often synchronize their steps. However, despite the importance of haptic interaction in general and the natural use of hand contact between humans during walking, few studies have investigated forces arising from physical interactions. Eight pairs of adult subjects participated in this study. They walked on side-by-side treadmills at 4 km/h independently and with hand contact. Only hand contact-related sensory information was available for unintentional synchronization, while visual and auditory communication was obstructed. Subjects walked at their natural cadences or following a metronome. Limb kinematics, hand contact 3D interaction forces and EMG activity of 12 upper limb muscles were recorded. Overall, unintentional step frequency locking was observed during about 40% of time in 88% of pairs walking with hand contact. On average, the amplitude of contact arm oscillations decreased while the contralateral (free) arm oscillated in the same way as during normal walking. Interestingly, EMG activity of the shoulder muscles of the contact arm did not decrease, and their synergistic pattern remained similar. The amplitude of interaction forces and of trunk oscillations was similar for synchronized and non-synchronized steps, though the synchronized steps were characterized by significantly more regular orientations of interaction forces. Our results further support the notion that gait synchronization during natural walking is common, and that it may occur through interaction forces. Conservation of the proximal muscle activity of the contact (not oscillating) arm is consistent with neural coupling between cervical and lumbosacral pattern generation circuitries (“quadrupedal” arm-leg coordination) during human gait. Overall, the findings suggest that individuals might integrate force interaction cues to communicate and coordinate steps during walking.
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Affiliation(s)
- Francesca Sylos-Labini
- Laboratory of Neuromotor Physiology, Santa Lucia Foundation, Rome, Italy.,Centre of Space Bio-medicine, University of Rome Tor Vergata, Rome, Italy
| | - Andrea d'Avella
- Laboratory of Neuromotor Physiology, Santa Lucia Foundation, Rome, Italy.,Department of Biomedical and Dental Sciences and Morphofunctional Imaging, University of Messina, Messina, Italy
| | - Francesco Lacquaniti
- Laboratory of Neuromotor Physiology, Santa Lucia Foundation, Rome, Italy.,Centre of Space Bio-medicine, University of Rome Tor Vergata, Rome, Italy.,Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy
| | - Yury Ivanenko
- Laboratory of Neuromotor Physiology, Santa Lucia Foundation, Rome, Italy
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14
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Lacquaniti F, Ivanenko YP, Sylos-Labini F, La Scaleia V, La Scaleia B, Willems PA, Zago M. Human Locomotion in Hypogravity: From Basic Research to Clinical Applications. Front Physiol 2017; 8:893. [PMID: 29163225 PMCID: PMC5682019 DOI: 10.3389/fphys.2017.00893] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Accepted: 10/24/2017] [Indexed: 01/07/2023] Open
Abstract
We have considerable knowledge about the mechanisms underlying compensation of Earth gravity during locomotion, a knowledge obtained from physiological, biomechanical, modeling, developmental, comparative, and paleoanthropological studies. By contrast, we know much less about locomotion and movement in general under sustained hypogravity. This lack of information poses a serious problem for human space exploration. In a near future humans will walk again on the Moon and for the first time on Mars. It would be important to predict how they will move around, since we know that locomotion and mobility in general may be jeopardized in hypogravity, especially when landing after a prolonged weightlessness of the space flight. The combination of muscle weakness, of wearing a cumbersome spacesuit, and of maladaptive patterns of locomotion in hypogravity significantly increase the risk of falls and injuries. Much of what we currently know about locomotion in hypogravity derives from the video archives of the Apollo missions on the Moon, the experiments performed with parabolic flight or with body weight support on Earth, and the theoretical models. These are the topics of our review, along with the issue of the application of simulated hypogravity in rehabilitation to help patients with deambulation problems. We consider several issues that are common to the field of space science and clinical rehabilitation: the general principles governing locomotion in hypogravity, the methods used to reduce gravity effects on locomotion, the extent to which the resulting behavior is comparable across different methods, the important non-linearities of several locomotor parameters as a function of the gravity reduction, the need to use multiple methods to obtain reliable results, and the need to tailor the methods individually based on the physiology and medical history of each person.
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Affiliation(s)
- Francesco Lacquaniti
- Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy
- Center of Space BioMedicine, University of Rome Tor Vergata, Rome, Italy
- Laboratory of Neuromotor Physiology, IRCCS Santa Lucia Foundation, Rome, Italy
| | - Yury P. Ivanenko
- Laboratory of Neuromotor Physiology, IRCCS Santa Lucia Foundation, Rome, Italy
| | - Francesca Sylos-Labini
- Center of Space BioMedicine, University of Rome Tor Vergata, Rome, Italy
- Laboratory of Neuromotor Physiology, IRCCS Santa Lucia Foundation, Rome, Italy
| | - Valentina La Scaleia
- Center of Space BioMedicine, University of Rome Tor Vergata, Rome, Italy
- Laboratory of Neuromotor Physiology, IRCCS Santa Lucia Foundation, Rome, Italy
| | - Barbara La Scaleia
- Laboratory of Neuromotor Physiology, IRCCS Santa Lucia Foundation, Rome, Italy
| | - Patrick A. Willems
- Laboratory of Biomechanics and Physiology of Locomotion, Institute of NeuroScience, Université catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Myrka Zago
- Laboratory of Neuromotor Physiology, IRCCS Santa Lucia Foundation, Rome, Italy
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15
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Richter C, Braunstein B, Winnard A, Nasser M, Weber T. Human Biomechanical and Cardiopulmonary Responses to Partial Gravity - A Systematic Review. Front Physiol 2017; 8:583. [PMID: 28860998 PMCID: PMC5559498 DOI: 10.3389/fphys.2017.00583] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2017] [Accepted: 07/28/2017] [Indexed: 11/30/2022] Open
Abstract
The European Space Agency has recently announced to progress from low Earth orbit missions on the International Space Station to other mission scenarios such as exploration of the Moon or Mars. Therefore, the Moon is considered to be the next likely target for European human space explorations. Compared to microgravity (μg), only very little is known about the physiological effects of exposure to partial gravity (μg < partial gravity <1 g). However, previous research studies and experiences made during the Apollo missions comprise a valuable source of information that should be taken into account when planning human space explorations to reduced gravity environments. This systematic review summarizes the different effects of partial gravity (0.1-0.4 g) on the human musculoskeletal, cardiovascular and respiratory systems using data collected during the Apollo missions as well as outcomes from terrestrial models of reduced gravity with either 1 g or microgravity as a control. The evidence-based findings seek to facilitate decision making concerning the best medical and exercise support to maintain astronauts' health during future missions in partial gravity. The initial search generated 1,323 publication hits. Out of these 1,323 publications, 43 studies were included into the present analysis and relevant data were extracted. None of the 43 included studies investigated long-term effects. Studies investigating the immediate effects of partial gravity exposure reveal that cardiopulmonary parameters such as heart rate, oxygen consumption, metabolic rate, and cost of transport are reduced compared to 1 g, whereas stroke volume seems to increase with decreasing gravity levels. Biomechanical studies reveal that ground reaction forces, mechanical work, stance phase duration, stride frequency, duty factor and preferred walk-to-run transition speed are reduced compared to 1 g. Partial gravity exposure below 0.4 g seems to be insufficient to maintain musculoskeletal and cardiopulmonary properties in the long-term. To compensate for the anticipated lack of mechanical and metabolic stimuli some form of exercise countermeasure appears to be necessary in order to maintain reasonable astronauts' health, and thus ensure both sufficient work performance and mission safety.
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Affiliation(s)
- Charlotte Richter
- Space Medicine Office (HRE-AM), European Astronaut Centre Department (HRE-A)Cologne, Germany
- Institute of Biomechanics und Orthopaedics, German Sport UniversityCologne, Germany
| | - Bjoern Braunstein
- Institute of Biomechanics und Orthopaedics, German Sport UniversityCologne, Germany
- Centre for Health and Integrative Physiology in SpaceCologne, Germany
- German Research Centre for Elite SportCologne, Germany
| | - Andrew Winnard
- Faculty of Health and Life Sciences, Northumbria UniversityNewcastle upon Tyne, United Kingdom
| | - Mona Nasser
- Peninsula Dental School, Plymouth UniversityPlymouth, United Kingdom
| | - Tobias Weber
- Space Medicine Office (HRE-AM), European Astronaut Centre Department (HRE-A)Cologne, Germany
- KBRwyle, Wyle Laboratories GmbH, Science, Technology and Engineering GroupCologne, Germany
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16
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von Zitzewitz J, Asboth L, Fumeaux N, Hasse A, Baud L, Vallery H, Courtine G. A neurorobotic platform for locomotor prosthetic development in rats and mice. J Neural Eng 2016; 13:026007. [DOI: 10.1088/1741-2560/13/2/026007] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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17
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Vasudevan EV, Patrick SK, Yang JF. Gait Transitions in Human Infants: Coping with Extremes of Treadmill Speed. PLoS One 2016; 11:e0148124. [PMID: 26828941 PMCID: PMC4734668 DOI: 10.1371/journal.pone.0148124] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Accepted: 01/13/2016] [Indexed: 11/18/2022] Open
Abstract
Spinal pattern generators in quadrupedal animals can coordinate different forms of locomotion, like trotting or galloping, by altering coordination between the limbs (interlimb coordination). In the human system, infants have been used to study the subcortical control of gait, since the cerebral cortex and corticospinal tract are immature early in life. Like other animals, human infants can modify interlimb coordination to jump or step. Do human infants possess functional neuronal circuitry necessary to modify coordination within a limb (intralimb coordination) in order to generate distinct forms of alternating bipedal gait, such as walking and running? We monitored twenty-eight infants (7–12 months) stepping on a treadmill at speeds ranging between 0.06–2.36 m/s, and seventeen adults (22–47 years) walking or running at speeds spanning the walk-to-run transition. Six of the adults were tested with body weight support to mimic the conditions of infant stepping. We found that infants could accommodate a wide range of speeds by altering stride length and frequency, similar to adults. Moreover, as the treadmill speed increased, we observed periods of flight during which neither foot was in ground contact in infants and in adults. However, while adults modified other aspects of intralimb coordination and the mechanics of progression to transition to a running gait, infants did not make comparable changes. The lack of evidence for distinct walking and running patterns in infants suggests that the expression of different functional, alternating gait patterns in humans may require neuromuscular maturation and a period of learning post-independent walking.
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Affiliation(s)
- Erin V. Vasudevan
- Rehabilitation Research and Movement Performance (RRAMP) Lab, Health and Rehabilitation Sciences, School of Health Technology and Management, Stony Brook University, Stony Brook, New York, United States of America
- * E-mail:
| | - Susan K. Patrick
- Department of Physical Therapy, University of Alberta, Edmonton, Alberta, Canada
| | - Jaynie F. Yang
- Department of Physical Therapy, University of Alberta, Edmonton, Alberta, Canada
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada
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18
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Fennell J, Goodwin C, Burn JF, Leonards U. How visual perceptual grouping influences foot placement. ROYAL SOCIETY OPEN SCIENCE 2015; 2:150151. [PMID: 26587273 PMCID: PMC4632586 DOI: 10.1098/rsos.150151] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/17/2015] [Accepted: 06/09/2015] [Indexed: 06/05/2023]
Abstract
Everybody would agree that vision guides locomotion; but how does vision influence choice when there are different solutions for possible foot placement? We addressed this question by investigating the impact of perceptual grouping on foot placement in humans. Participants performed a stepping stone task in which pathways consisted of target stones in a spatially regular path of foot falls and visual distractor stones in their proximity. Target and distractor stones differed in shape and colour so that each subset of stones could be easily grouped perceptually. In half of the trials, one target stone swapped shape and colour with a distractor in its close proximity. We show that in these 'swapped' conditions, participants chose the perceptually groupable, instead of the spatially regular, stepping location in over 40% of trials, even if the distance between perceptually groupable steps was substantially larger than normal step width/length. This reveals that the existence of a pathway that could be traversed without spatial disruption to periodic stepping is not sufficient to guarantee participants will select it and suggests competition between different types of visual input when choosing foot placement. We propose that a bias in foot placement choice in favour of visual grouping exists as, in nature, sudden changes in visual characteristics of the ground increase the uncertainty for stability.
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Affiliation(s)
- John Fennell
- School of Experimental Psychology, University of Bristol, 12a Priory Road, Bristol BS8 1TU, UK
| | - Charlotte Goodwin
- School of Experimental Psychology, University of Bristol, 12a Priory Road, Bristol BS8 1TU, UK
| | - Jeremy F. Burn
- Department of Mechanical Engineering, Queen's Building, University of Bristol, University Walk, Bristol BS8 1TR, UK
| | - Ute Leonards
- School of Experimental Psychology, University of Bristol, 12a Priory Road, Bristol BS8 1TU, UK
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19
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Mari S, Serrao M, Casali C, Conte C, Martino G, Ranavolo A, Coppola G, Draicchio F, Padua L, Sandrini G, Pierelli F. Lower limb antagonist muscle co-activation and its relationship with gait parameters in cerebellar ataxia. THE CEREBELLUM 2014; 13:226-36. [PMID: 24170572 DOI: 10.1007/s12311-013-0533-4] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Increased antagonist muscle co-activation, seen in motor-impaired individuals, is an attempt by the neuromuscular system to provide mechanical stability by stiffening joints. The aim of this study was to investigate the co-activation pattern of the antagonist muscles of the ankle and knee joints during walking in patients with cerebellar ataxia, a neurological disease that strongly affects stability. Kinematic and electromyographic parameters of gait were recorded in 17 patients and 17 controls. Ankle and knee antagonist muscle co-activation indexes were measured throughout the gait cycle and during the sub-phases of gait. The indexes of ataxic patients were compared with those of controls and correlated with clinical and gait variables. Patients showed increased co-activity indexes of both ankle and knee muscles during the gait cycle as well as during the gait sub-phases. Both knee and ankle muscle co-activation indexes were positively correlated with disease severity, while ankle muscle co-activation was also positively correlated with stance and swing duration variability. Significant negative correlations were observed between the number of self-reported falls per year and knee muscle co-activation. The increased co-activation observed in these cerebellar ataxia patients may represent a compensatory strategy serving to reduce gait instability. Indeed, this mechanism allows patients to reduce the occurrence of falls. The need for this strategy, which results in excessive muscle co-contraction, increased metabolic costs and cartilage degeneration processes, could conceivably be overcome through the use of supportive braces specially designed to provide greater joint stability.
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20
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Human locomotion under reduced gravity conditions: biomechanical and neurophysiological considerations. BIOMED RESEARCH INTERNATIONAL 2014; 2014:547242. [PMID: 25247179 PMCID: PMC4163425 DOI: 10.1155/2014/547242] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Accepted: 06/12/2014] [Indexed: 12/26/2022]
Abstract
Reduced gravity offers unique opportunities to study motor behavior. This paper aims at providing a review on current issues of the known tools and techniques used for hypogravity simulation and their effects on human locomotion. Walking and running rely on the limb oscillatory mechanics, and one way to change its dynamic properties is to modify the level of gravity. Gravity has a strong effect on the optimal rate of limb oscillations, optimal walking speed, and muscle activity patterns, and gait transitions occur smoothly and at slower speeds at lower gravity levels. Altered center of mass movements and interplay between stance and swing leg dynamics may challenge new forms of locomotion in a heterogravity environment. Furthermore, observations in the lack of gravity effects help to reveal the intrinsic properties of locomotor pattern generators and make evident facilitation of nonvoluntary limb stepping. In view of that, space neurosciences research has participated in the development of new technologies that can be used as an effective tool for gait rehabilitation.
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21
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Sylos-Labini F, La Scaleia V, d'Avella A, Pisotta I, Tamburella F, Scivoletto G, Molinari M, Wang S, Wang L, van Asseldonk E, van der Kooij H, Hoellinger T, Cheron G, Thorsteinsson F, Ilzkovitz M, Gancet J, Hauffe R, Zanov F, Lacquaniti F, Ivanenko YP. EMG patterns during assisted walking in the exoskeleton. Front Hum Neurosci 2014; 8:423. [PMID: 24982628 PMCID: PMC4058900 DOI: 10.3389/fnhum.2014.00423] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2014] [Accepted: 05/27/2014] [Indexed: 12/30/2022] Open
Abstract
Neuroprosthetic technology and robotic exoskeletons are being developed to facilitate stepping, reduce muscle efforts, and promote motor recovery. Nevertheless, the guidance forces of an exoskeleton may influence the sensory inputs, sensorimotor interactions and resulting muscle activity patterns during stepping. The aim of this study was to report the muscle activation patterns in a sample of intact and injured subjects while walking with a robotic exoskeleton and, in particular, to quantify the level of muscle activity during assisted gait. We recorded electromyographic (EMG) activity of different leg and arm muscles during overground walking in an exoskeleton in six healthy individuals and four spinal cord injury (SCI) participants. In SCI patients, EMG activity of the upper limb muscles was augmented while activation of leg muscles was typically small. Contrary to our expectations, however, in neurologically intact subjects, EMG activity of leg muscles was similar or even larger during exoskeleton-assisted walking compared to normal overground walking. In addition, significant variations in the EMG waveforms were found across different walking conditions. The most variable pattern was observed in the hamstring muscles. Overall, the results are consistent with a non-linear reorganization of the locomotor output when using the robotic stepping devices. The findings may contribute to our understanding of human-machine interactions and adaptation of locomotor activity patterns.
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Affiliation(s)
- Francesca Sylos-Labini
- Laboratory of Neuromotor Physiology, Santa Lucia Foundation Rome, Italy ; Centre of Space Bio-medicine, University of Rome Tor Vergata Rome, Italy
| | - Valentina La Scaleia
- Laboratory of Neuromotor Physiology, Santa Lucia Foundation Rome, Italy ; Centre of Space Bio-medicine, University of Rome Tor Vergata Rome, Italy
| | - Andrea d'Avella
- Laboratory of Neuromotor Physiology, Santa Lucia Foundation Rome, Italy
| | - Iolanda Pisotta
- Spinal Cord Rehab Unit and CaRMA Lab, Santa Lucia Foundation Rome, Italy
| | | | - Giorgio Scivoletto
- Spinal Cord Rehab Unit and CaRMA Lab, Santa Lucia Foundation Rome, Italy
| | - Marco Molinari
- Spinal Cord Rehab Unit and CaRMA Lab, Santa Lucia Foundation Rome, Italy
| | - Shiqian Wang
- Biomechanical Engineering, Delft University of Technology Delft, Netherlands
| | - Letian Wang
- Biomechanical Engineering, University of Twente Enschede, Netherlands
| | | | - Herman van der Kooij
- Biomechanical Engineering, Delft University of Technology Delft, Netherlands ; Biomechanical Engineering, University of Twente Enschede, Netherlands
| | - Thomas Hoellinger
- Laboratory of Neurophysiology and Movement Biomechanics, Université Libre de Bruxelles Brussels, Belgium
| | - Guy Cheron
- Laboratory of Neurophysiology and Movement Biomechanics, Université Libre de Bruxelles Brussels, Belgium
| | | | | | - Jeremi Gancet
- Space Applications Services N.V./S.A. Zaventem, Belgium
| | | | | | - Francesco Lacquaniti
- Laboratory of Neuromotor Physiology, Santa Lucia Foundation Rome, Italy ; Centre of Space Bio-medicine, University of Rome Tor Vergata Rome, Italy ; Department of Systems Medicine, University of Rome Tor Vergata Rome, Italy
| | - Yuri P Ivanenko
- Laboratory of Neuromotor Physiology, Santa Lucia Foundation Rome, Italy
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22
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Sylos-Labini F, Ivanenko YP, MacLellan MJ, Cappellini G, Poppele RE, Lacquaniti F. Locomotor-like leg movements evoked by rhythmic arm movements in humans. PLoS One 2014; 9:e90775. [PMID: 24608249 PMCID: PMC3946538 DOI: 10.1371/journal.pone.0090775] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Accepted: 02/04/2014] [Indexed: 12/21/2022] Open
Abstract
Motion of the upper limbs is often coupled to that of the lower limbs in human bipedal locomotion. It is unclear, however, whether the functional coupling between upper and lower limbs is bi-directional, i.e. whether arm movements can affect the lumbosacral locomotor circuitry. Here we tested the effects of voluntary rhythmic arm movements on the lower limbs. Participants lay horizontally on their side with each leg suspended in an unloading exoskeleton. They moved their arms on an overhead treadmill as if they walked on their hands. Hand-walking in the antero-posterior direction resulted in significant locomotor-like movements of the legs in 58% of the participants. We further investigated quantitatively the responses in a subset of the responsive subjects. We found that the electromyographic (EMG) activity of proximal leg muscles was modulated over each cycle with a timing similar to that of normal locomotion. The frequency of kinematic and EMG oscillations in the legs typically differed from that of arm oscillations. The effect of hand-walking was direction specific since medio-lateral arm movements did not evoke appreciably leg air-stepping. Using externally imposed trunk movements and biomechanical modelling, we ruled out that the leg movements associated with hand-walking were mainly due to the mechanical transmission of trunk oscillations. EMG activity in hamstring muscles associated with hand-walking often continued when the leg movements were transiently blocked by the experimenter or following the termination of arm movements. The present results reinforce the idea that there exists a functional neural coupling between arm and legs.
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Affiliation(s)
- Francesca Sylos-Labini
- Laboratory of Neuromotor Physiology, Santa Lucia Foundation, Rome, Italy
- Centre of Space Bio-medicine, University of Rome Tor Vergata, Rome, Italy
| | - Yuri P. Ivanenko
- Laboratory of Neuromotor Physiology, Santa Lucia Foundation, Rome, Italy
| | - Michael J. MacLellan
- Laboratory of Neuromotor Physiology, Santa Lucia Foundation, Rome, Italy
- Louisiana State University, School of Kinesiology, Baton Rouge, Louisiana, United States of America
| | - Germana Cappellini
- Laboratory of Neuromotor Physiology, Santa Lucia Foundation, Rome, Italy
- Centre of Space Bio-medicine, University of Rome Tor Vergata, Rome, Italy
| | - Richard E. Poppele
- Department of Neuroscience, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Francesco Lacquaniti
- Laboratory of Neuromotor Physiology, Santa Lucia Foundation, Rome, Italy
- Centre of Space Bio-medicine, University of Rome Tor Vergata, Rome, Italy
- Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy
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23
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Sylos-Labini F, Ivanenko YP, Cappellini G, Portone A, MacLellan MJ, Lacquaniti F. Changes of gait kinematics in different simulators of reduced gravity. J Mot Behav 2013; 45:495-505. [PMID: 24079466 DOI: 10.1080/00222895.2013.833080] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Gravity reduction affects the energetics and natural speed of walking and running. But, it is less clear how segmental coordination is altered. Various devices have been developed in the past to study locomotion in simulated reduced gravity. However, most of these devices unload only the body center of mass. The authors reduced the effective gravity acting on the stance or swing leg to 0.16g using different simulators. Locomotion under these conditions was associated with a reduction in the foot velocity and significant changes in angular motion. Moreover, when simulated reduced gravity directly affected the swing limb, it resulted in significantly slower swing and longer foot excursions, suggesting an important role of the swing phase dynamics in shaping locomotor patterns.
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24
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Duysens J, De Groote F, Jonkers I. The flexion synergy, mother of all synergies and father of new models of gait. Front Comput Neurosci 2013; 7:14. [PMID: 23494365 PMCID: PMC3595503 DOI: 10.3389/fncom.2013.00014] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Accepted: 02/20/2013] [Indexed: 12/22/2022] Open
Abstract
Recently there has been a growing interest in the modular organization of leg movements, in particular those related to locomotion. One of the basic modules involves the flexion of the leg during swing and it was shown that this module is already present in neonates (Dominici et al., 2011). In this paper, we question how these finding build upon the original work by Sherrington, who proposed that the flexor reflex is the basic building block of flexion during swing phase. Similarly, the relation between the flexor reflex and the withdrawal reflex modules of Schouenborg and Weng (1994) will be discussed. It will be argued that there is large overlap between these notions on modules and the older concepts of reflexes. In addition, it will be shown that there is a great flexibility in the expression of some of these modules during gait, thereby allowing for a phase-dependent modulation of the appropriate responses. In particular, the end of the stance phase is a period when the flexor synergy is facilitated. It is proposed that this is linked to the activation of circuitry that is responsible for the generation of locomotor patterns (CPG, “central pattern generator”). More specifically, it is suggested that the responses in that period relate to the activation of a flexor burst generator. The latter structure forms the core of a new asymmetric model of the CPG. This activation is controlled by afferent input (facilitation by a broad range of afferents, suppression by load afferent input). Meanwhile, many of these physiologic features have found their way in the control of very flexible walking bipedal robots.
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Affiliation(s)
- Jacques Duysens
- Department of Kinesiology, KU Leuven Heverlee, Belgium ; Department of Research, Sint Maartenskliniek Nijmegen, Netherlands
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25
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Chong SY, Wagner H, Wulf A. Application of neural oscillators to study the effects of walking speed on rhythmic activations at the ankle. Theor Biol Med Model 2013; 10:9. [PMID: 23405859 PMCID: PMC3600020 DOI: 10.1186/1742-4682-10-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2012] [Accepted: 02/08/2013] [Indexed: 11/25/2022] Open
Abstract
Background Spinal pattern generators (SPG) are neural networks in the spinal cord that do not require a central input from the brain to generate a motor output. We wanted to determine whether SPG can adapt to the changing motor demands from walking at different speeds, and performing silly walks. Methods An SPG model consisting of an oscillator made up of two neurons was utilised in this study; one neuron activates the soleus and the other activates the tibialis anterior. The outputs of the SPG model therefore represent the electromyographic measurements from each muscle. Seven healthy subjects were requested to perform silly walks, normal walking at self-selected speed (4.8 ± 0.5 km/h), 3.5 km/h, 4.0 km/h and 4.5 km/h on a treadmill. Loading and hip angles were used as inputs into the model. Results No significant differences in the model parameters were found between normal walking at self-selected speed and other walking speeds. Only the adaptation time constant for the ankle flexor during silly walks was significantly different from the other normal walking trials. Conclusion We showed that SPG in the spinal cord can interpret and respond accordingly to velocity-dependent afferent information. Changes in walking speed do not require a different motor control mechanism provided there is no disruption to the alternating muscular activations generated at the ankle.
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Affiliation(s)
- Sook-Yee Chong
- Department of Motion Science, University of Muenster, Muenster, Germany
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26
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Functional Roles of Phase Resetting in the Gait Transition of a Biped Robot From Quadrupedal to Bipedal Locomotion. IEEE T ROBOT 2012. [DOI: 10.1109/tro.2012.2205489] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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27
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Maclellan MJ, Ivanenko YP, Cappellini G, Sylos Labini F, Lacquaniti F. Features of hand-foot crawling behavior in human adults. J Neurophysiol 2011; 107:114-25. [PMID: 21975454 DOI: 10.1152/jn.00693.2011] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Interlimb coordination of crawling kinematics in humans shares features with other primates and nonprimate quadrupeds, and it has been suggested that this is due to a similar organization of the locomotor pattern generators (CPGs). To extend the previous findings and to further explore the neural control of bipedal vs. quadrupedal locomotion, we used a crawling paradigm in which healthy adults crawled on their hands and feet at different speeds and at different surface inclinations (13°, 27°, and 35°). Ground reaction forces, limb kinematics, and electromyographic (EMG) activity from 26 upper and lower limb muscles on the right side of the body were collected. The EMG activity was mapped onto the spinal cord in approximate rostrocaudal locations of the motoneuron pools to characterize the general features of cervical and lumbosacral spinal cord activation. The spatiotemporal pattern of spinal cord activity significantly differed between quadrupedal and bipedal gaits. In addition, participants exhibited a large range of kinematic coordination styles (diagonal vs. lateral patterns), which is in contrast to the stereotypical kinematics of upright bipedal walking, suggesting flexible coupling of cervical and lumbosacral pattern generators. Results showed strikingly dissimilar directional horizontal forces for the arms and legs, considerably retracted average leg orientation, and substantially smaller sacral vs. lumbar motoneuron activity compared with quadrupedal gait in animals. A gradual transition to a more vertical body orientation (increasing the inclination of the treadmill) led to the appearance of more prominent sacral activity (related to activation of ankle plantar flexors), typical of bipedal walking. The findings highlight the reorganization and adaptation of CPG networks involved in the control of quadrupedal human locomotion and a high specialization of the musculoskeletal apparatus to specific gaits.
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Affiliation(s)
- M J Maclellan
- Laboratory of Neuromotor Physiology, IRCCS Fondazione Santa Lucia, 306 via Ardeatina, 00179 Rome, Italy.
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