Article
Physiology
Kenzo C. Kishimoto, Martin E. Heroux, Simon C. Gandevia, Jane E. Butler, Joanna Diong
Summary: This study demonstrated that maximal muscle activity can be estimated from muscle activity produced during submaximal voluntary activation. A simple mathematical relationship between voluntary muscle activation and muscle activity across a broad range of values was found, capable of estimating maximal muscle activity.
JOURNAL OF APPLIED PHYSIOLOGY
(2021)
Article
Biology
Anthony L. Hessel, Brent J. Raiteri, Michael J. Marsh, Daniel Hahn
Summary: The study found that under submaximal voluntary muscle contractions, the torque-angle and force-fascicle length curves of the soleus and lateral gastrocnemius muscles shifted towards more dorsiflexed ankle angles and longer fascicle lengths. This shift may have implications for human locomotion such as walking, as the operating range of fascicles shifts to the ascending limb where muscle force capacity is reduced by at least 15%.
JOURNAL OF EXPERIMENTAL BIOLOGY
(2021)
Article
Environmental Sciences
Yin Wang, Ming Xu, Lingling Wang, Sha Shi, Chenhui Zhang, Xiaobin Wu, Hua Wang, Xiahui Xiong, Chunling Wang
Summary: In this study, a three-dimensional internal wave (IW)-cylinder-terrain coupled numerical model is established to explore the IW mechanical characteristics of the cylinder and the flow field evolution around the cylinder over different types of terrains. The research results show that the waveform structures of IWs propagate over terrain are prone to continuous changes. The intense reverse alternating flow of the upper and the lower water, bounded by the pycnocline, results in huge IWs forces differences between the case without terrains and the cases with terrains.
Article
Sport Sciences
Kenneth G. Harlan, Roberto B. Merucci, Jalen J. Weaver, Thomas C. Windle, Moh H. Malek
Summary: This study investigated the influence of pre-exhaustion exercise on the electromyographic fatigue threshold (EMG(FT)), finding that EMG(FT) values decreased in healthy active subjects but remained unchanged in elite runners. These results suggest that the impact of pre-exhaustion exercise may be influenced by the subject's habitual exercise history.
JOURNAL OF STRENGTH AND CONDITIONING RESEARCH
(2021)
Article
Engineering, Biomedical
Jack Tchimino, Marko Markovic, Jakob Lund Dideriksen, Strahinja Dosen
Summary: This study investigated the impact of cutoff frequency and normalization value on the quality of closed-loop control with EMG feedback. The experiments showed that lower cutoff frequency and higher normalization value resulted in better control performance for EMG feedback, with the optimal combination being 40% MVC and 0.5 Hz cutoff frequency.
JOURNAL OF NEURAL ENGINEERING
(2021)
Article
Robotics
Minghan Wei, Volkan Isler
Summary: This letter introduces a data-driven approach for optimizing energy consumption in robot navigation on large, uneven terrains using a neural network model. Trained on field-collected data, this method demonstrates better generalization performance in new environments.
IEEE ROBOTICS AND AUTOMATION LETTERS
(2022)
Article
Neurosciences
Jack Tchimino, Jakob Lund Dideriksen, Strahinja Dosen
Summary: Closing the prosthesis control loop with artificial somatosensory feedback can enhance the functionality and user experience. This study compares the performance of EMG and force feedback in the presence of control disturbances and finds that EMG feedback outperforms force feedback in terms of reaction to disturbance and completion time.
FRONTIERS IN NEUROSCIENCE
(2022)
Article
Engineering, Biomedical
Xinyu Jiang, Xiangyu Liu, Jiahao Fan, Chenyun Dai, Edward A. Clancy, Wei Chen
Summary: Estimating finger forces from sEMG is important for various applications, but the performance of pre-trained models can degrade significantly on different days. This study investigates the effect of model regularization and explores the use of random channel masks to improve cross-day model performance. Results show that combining random channel masks with Moore-Penrose inverse model regularization can significantly enhance the model's performance in cross-day validation.
IEEE TRANSACTIONS ON NEURAL SYSTEMS AND REHABILITATION ENGINEERING
(2022)
Article
Neurosciences
Giovanni Martino, Owen N. Beck, Lena H. Ting
Summary: Muscle coactivation increases in challenging balance conditions, advanced age, and mobility impairments. However, the causal relationship between feedforward and feedback muscle coactivation remains elusive. In young adults, voluntary feedforward muscle coactivation does not increase feedback coactivation but enables faster joint torque generation through reciprocal agonist-antagonist muscle activity.
JOURNAL OF NEUROPHYSIOLOGY
(2023)
Article
Biophysics
Carlos De la Fuente, Eduardo Martinez-Valdes, Emmanuel S. da Rocha, Jeam M. Geremia, Marco A. Vaz, Felipe P. Carpes
Summary: Structural alterations of the triceps surae and Achilles tendon following a repair surgery can lead to plantarflexion weakness and influence the activation strategies of the Gastrocnemius Medialis (GM) muscle. This study aimed to investigate the spatial activation patterns of GM in patients with persistent plantar flexion weakness one-year post-surgery. The results showed increased distal overactivation in GM in patients with persistent weakness, indicating altered activation patterns in this muscle group following Achilles tendon repair.
JOURNAL OF BIOMECHANICS
(2023)
Article
Engineering, Electrical & Electronic
Yei Hwan Jung, Jae-Young Yoo, Abraham Vazquez-Guardado, Jae-Hwan Kim, Jin-Tae Kim, Haiwen Luan, Minsu Park, Jaeman Lim, Hee-Sup Shin, Chun-Ju Su, Robert Schloen, Jacob Trueb, Raudel Avila, Jan-Kai Chang, Da Som Yang, Yoonseok Park, Hanjun Ryu, Hong-Joon Yoon, Geumbee Lee, Hyoyeong Jeong, Jong Uk Kim, Aadeel Akhtar, Jesse Cornman, Tae-il Kim, Yonggang Huang, John A. Rogers
Summary: This technology allows for the transmission of vibro-tactile patterns on the skin to convey navigation instructions, translate music into tactile patterns, and provide sensory feedback for robotic prosthetics. The system is lightweight and flexible, offering full-body coverage for tactile sensations.
NATURE ELECTRONICS
(2022)
Article
Neurosciences
Anuj Ojha, Gordon Alderink, Samhita Rhodes
Summary: This study examined the neural correlations during muscle activation related to balance. The results showed greater coherence between muscle pairs in the same leg and in lower frequency bands. The coherence between different muscle pairs was higher in less stable positions. The findings suggest that coherence between EMG signals can be used as an independent indicator of the neural correlates for stability.
FRONTIERS IN HUMAN NEUROSCIENCE
(2023)
Article
Sport Sciences
Takehiro Kosaka, Shuhei Sasajima, Ayaka Yasuda, Soushi Mino, Keitaro Kubo
Summary: This study investigated the effects of tendon elastic energy and electromyographic activity patterns on jump performance. The results showed that jumping exercises with low pre-stretch intensity primarily benefited from tendon elastic energy, while those with high pre-stretch intensity primarily benefited from electromyographic activity patterns.
JOURNAL OF SPORTS SCIENCES
(2023)
Article
Engineering, Mechanical
H. Zhang, H. H. Ding, X. L. Cui, Y. Wang, Z. Y. Han, E. Meli, W. J. Wang
Summary: The effect of contact forces on rail uneven longitudinal wear was studied through rolling tests. The results showed that the tangential force had a greater impact on wear than the normal force. Under the same tangential force, wear was more severe under lower normal forces, and as the normal force increased, wear decreased. Similarly, under the same normal force, wear was more severe under higher tangential forces. The main types of damage observed were oxidative wear and fatigue wear.
Article
Engineering, Industrial
Jiyun Ahn, Caroline Simpkins, Feng Yang
Summary: This study examined the effects of anterior-loading on kinetics and muscle activities during walking. The results showed that increased load led to greater activation of the gluteus maximus, suggesting it may play a role in stabilizing the trunk during anterior-loaded walking.
INTERNATIONAL JOURNAL OF INDUSTRIAL ERGONOMICS
(2022)
Article
Clinical Neurology
Torsten Sauder, Philipp M. Keune, Roy Mueller, Thomas Schenk, Patrick Oschmann, Sascha Hansen
Summary: The study found a strong negative correlation between trait mindfulness and depression and fatigue in PwMS. However, further analysis revealed that depression mediated the relationship between mindfulness and fatigue. This suggests that mindfulness may have a primary association with depression and a secondary association with fatigue in PwMS.
Article
Biophysics
Johanna Vielemeyer, Roy Mueller, Nora-Sophie Staufenberg, Daniel Renjewski, Rainer Abel
Summary: Research has shown that in different support phases of human walking, the direction of ground reaction forces and the height of the virtual pivot point may vary due to the vertical movement of the center of mass and differences in contact time.
JOURNAL OF BIOMECHANICS
(2021)
Article
Clinical Neurology
Roy Mueller, Daniel Hamacher, Sascha Hansen, Patrick Oschmann, Philipp M. Keune
Summary: The study found that gait parameters obtained by wearable inertial sensors can sensitively detect gait disturbances in early multiple sclerosis patients and these parameters are significantly correlated with fatigue.
Article
Multidisciplinary Sciences
Lucas Schreff, Daniel F. B. Haeufle, Johanna Vielemeyer, Roy Mueller
Summary: Previous studies focused on reflexes and central pattern generators in reaction to step-down perturbations, while experiments also showed preparatory adaptations based on visual anticipation. This study proposes a high-level anticipatory strategy to enhance low-level muscle-reflex control, and simulations demonstrate that this strategy increases robustness.
SCIENTIFIC REPORTS
(2022)
Article
Clinical Neurology
Christian Lassmann, Winfried Ilg, Marc Schneider, Maximilian Voelker, Daniel F. B. Haeufle, Rebecca Schuele, Martin Giese, Matthis Synofzik, Ludger Schoels, Tim W. Rattay
Summary: This study found specific movement abnormalities in potential SPG4 patients before the manifestation of gait impairment, which were correlated with neurodegenerative biomarkers and could help in early interventions.
MOVEMENT DISORDERS
(2022)
Article
Clinical Neurology
Roy Mueller, Daniel Hamacher, Philipp M. Keune, Patrick Oschmann
Summary: Currently, studies have shown that wearable inertial sensors are highly sensitive in detecting gait disturbances in PwMS, with excellent reliability within a short time frame. However, it is unknown how stable these gait parameters remain over a longer period. This study found that after one year, the mean gait parameters remained stable, making them clinically relevant markers for evaluating treatment effects over a longer period of time in MS.
Rating: 8/10
Article
Neurosciences
Lucas Schreff, Daniel F. B. Haeufle, Rainer Abel, Roy Mueller
Article
Biophysics
Lucas Schreff, Daniel F. B. Haeufle, Alexander Badri-Sproewitz, Johanna Vielemeyer, Roy Mueller
Summary: The intersection point (IP) of ground reaction forces near the center of mass has been commonly assumed to provide postural stability for bipedal walking. However, this study challenges this assumption by finding stable walking patterns without the typical IP characteristics. The results suggest that the role of the IP in postural stability and the potential alternative or additional function of the IP should be further investigated.
JOURNAL OF BIOMECHANICS
(2023)
Article
Multidisciplinary Sciences
Johanna Vielemeyer, Cristina Sole, Manuela Galli, Matteo Zago, Roy Mueller, Claudia Condoluci
Summary: This study compared the dynamic gait function of individuals with Down Syndrome to healthy controls using the concept of the virtual pivot point (VPP). The results showed that individuals with Down Syndrome had an anteriorly located VPP compared to healthy controls, likely due to larger hip moments during the propulsive phase of stance. High R-2 values in individuals with Down Syndrome suggest a strong association between the VPP and dynamic stability during walking.
Article
Clinical Neurology
Annalena Zahn, Veronika Koch, Lucas Schreff, Patrick Oschmann, Juergen Winkler, Heiko Gassner, Roy Mueller
Summary: The study aimed to evaluate the validity of an inertial sensor-based gait analysis system in people with multiple sclerosis (PwMS), compared to a marker-based camera system. The results showed that the inertial sensor system accurately captured all examined gait parameters, with slightly discrepancies in stride time and swing time.
FRONTIERS IN NEUROLOGY
(2023)
Article
Multidisciplinary Sciences
Johanna Vielemeyer, Nora-Sophie Staufenberg, Lucas Schreff, Daniel Rixen, Roy Mueller
Summary: Research found that humans imitating the humanoid robot LOLA showed no significant differences in speed, posture, and mass distribution compared to LOLA. Most participants exhibited the common virtual pivot point (VPP) observed in human and animal walking, while two participants did not show VPP during LOLA-like walking. This could be attributed to the unbalanced horizontal ground reaction forces during the single support phase, which is likely the key variable for the absence of VPP.
ROYAL SOCIETY OPEN SCIENCE
(2023)
Article
Multidisciplinary Sciences
Johanna Vielemeyer, Lucas Schreff, Stefan Hochstein, Roy Mueller
Summary: This study investigated the effects of manipulating the center of pressure on the kinetics and kinematics of human walking and its influence on the virtual pivot point (VPP). The results showed that the majority of participants exhibited a VPP in various conditions, with the exception of one participant during handstand walking. There were no significant differences in the horizontal and vertical position of the VPP between the conditions.
Article
Surgery
Clara Oette, Roy Mueller, Lucas Schreff, Rainer Abel
Summary: This study aimed to examine the effects of postural changes on pressure measurements in wheelchair users with spinal cord injury (SCI) during daily life activity. Measurements were taken using a seat pressure mat on 34 patients, and the results showed significant differences between the initial measurement and the measurements at 30 and 90 minutes later, but stability was achieved after 30 minutes. The activity of the participants between measurements did not appear to have a significant impact on the results.
INTERNATIONAL JOURNAL OF SPINE SURGERY
(2023)
Meeting Abstract
Anthropology
Fotios Alexandros Karakostis, Daniel Haeufle, Ioanna Anastopoulou, Konstantinos Moraitis, Gerhard Hotz, Vangelis Tourloukis, Katerina Harvati
AMERICAN JOURNAL OF BIOLOGICAL ANTHROPOLOGY
(2022)
