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1.
PeerJ ; 10: e14412, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36447512

RESUMEN

Background: Studies on motor imagery (MI) practice based on different designs and training protocols have reported changes in maximal voluntary contraction (MVC) strength. However, to date, there is a lack of information on the effects of MI training on contractile properties of the trained muscle. Methods: Forty-five physically active sport science students (21 female) were investigated who trained three times per week over a 4-week period in one of three groups: An MI group conducted MI practice of maximal isometric contraction of the biceps brachii; a physical exercise (PE) group physically practiced maximal isometric contractions of the biceps brachii in a biceps curling machine; and a visual imagery (VI) group performed VI training of a landscape. A MVC test of the arm flexors was performed in a biceps curling machine before and after 4 weeks of training. The muscular properties of the biceps brachii were also tested with tensiomyography measurements (TMG). Results: Results showed an interaction effect between time and group for MVC (p = 0.027, η 2 = 0.17), with a higher MVC value in the PE group (Δ5.9%) compared to the VI group (Δ -1.3%) (p = 0.013). MVC did not change significantly in the MI group (Δ2.1%). Analysis of muscle contractility via TMG did not show any interaction effects neither for maximal radial displacement (p = 0.394, η 2 = 0.05), delay time (p = 0.79, η 2 = 0.01) nor contraction velocity (p = 0.71, η 2 = 0.02). Conclusion: In spite of MVC-related changes in the PE group due to the interventions, TMG measurements were not sensitive enough to detect concomitant neuronal changes related to contractile properties.


Asunto(s)
Contracción Muscular , Músculo Esquelético , Humanos , Femenino , Electromiografía/métodos , Músculo Esquelético/fisiología , Contracción Muscular/fisiología , Brazo/fisiología , Estudiantes
2.
Exp Brain Res ; 240(9): 2435-2457, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35930013

RESUMEN

Reaching movements of the arms are accompanied by anticipatory (APM) and compensatory postural motion (CPM) that counteract the resulting perturbations to body stability. Recent research has shown that these postural actions are also observable in the context of imagined arm movements. As motor imagery (MI) shares many neurophysiological and behavioral characteristics with physical movements, and MI training can affect subsequent performance, MI tasks provide a good setting for studying the anticipatory aspects of postural control. This study investigated APMs and CPMs of the head and hip of healthy young and older adults in the temporal vicinity of physical and imagined forward raises of the dominant and non-dominant arm. When MI of the dominant arm was self-initiated, both age groups showed APM in the anteroposterior plane. When the self-initiated MI was of the non-dominant arm, only the older group showed anteroposterior APM. The older group did not show APM when an expected arm movement (or MI) was made to an external signal. This suggests an age-related deficit in coordinating postural preparation with external events. Only the older group showed mediolateral APM, and only for dominant arm MI, indicating sensitivity to potential perturbation to the weaker, non-dominant side of the body. Overall, the older group showed more anticipatory postural motion at the head. Systematic APM for manual MI suggests that MI training may be an effective intervention for anticipatory postural control. An integrated model of postural support for executed and imagined limb movements is suggested.


Asunto(s)
Brazo , Movimiento , Anciano , Brazo/fisiología , Electromiografía , Humanos , Imágenes en Psicoterapia , Movimiento/fisiología , Equilibrio Postural/fisiología
3.
Comput Intell Neurosci ; 2022: 2586716, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35755753

RESUMEN

In order to explore the kinematics and muscle force characteristics of competitive Taijiquan arm manipulation, and solve the problems of arm trajectory and control in the process of manipulation, this study puts forward the sports biomechanical analysis of arm manipulation in competitive Taijiquan. The technical characteristics and muscle force characteristics of 15 athletes from the competitive Taijiquan team of Xi'an Institute of physical education were studied. Use Excel 2007 and SPSS17.0 to statistically analyze and process the original data. According to the actual needs, the data indicators are summarized. The combined movements of competitive Taijiquan arm manipulation are captured through high-speed photography, and the kinematic data are statistically analyzed, mainly from the two aspects of action amplitude change and action braking. The results show the action track length, relative track length, and action track length of each plane of the two combined hands. The order of the two combined action tracks is: combination 1 > combination 2, in which the action track in the sagittal plane is the longest in combination 1, and it can also be considered that the motion amplitude in the sagittal plane is the largest in combination 1. The average acceleration of group A in the first beat is 0.51 m/s2 smaller than that of group B, and the value is 0.22 m/s2 smaller. Therefore, the deceleration of group A is larger than that of group B, and the braking capacity of group A is slightly stronger than that of group B. In the second beat, the average acceleration of group B is 1.5722 m/s2 larger than that of group A, and the value is 0.210 m/s2 larger. The average acceleration of group A in the third, fourth, fifth, and sixth beats is 0.9, 3.728, 0.57, and 0.837 m/s2 smaller than that of group B, and the values are 0.466, 0.174, 0.250, and 0.003 m/s2 smaller, indicating that the braking capacity of group A in the third, fourth, fifth, sixth, and eighth beats is slightly stronger than that of group B. In the braking of each beat in combination 1 and combination 2 of group AB, the braking ability of arm manipulation of group A is stronger than that of group B. In competitive Taijiquan, the movement techniques of manipulation include: bouncing technology, braking technology, and control technology. For arm manipulation, athletes should have the ability of "braking" technology. In the correlation analysis of movement track length, RMS and I EMG, the score of athletes in group A is high, and there is no correlation between movement track length and RMS. There is a significant correlation between RMS and movement track length in group B, and the correlation degree is moderate. This shows that when the movement of group B athletes is completed, the muscles are in a state of tension, the movement skills are not mastered well, and the energy saving is not achieved. During training, we should pay more attention to the proprioception of muscles and form a correct way of muscle exertion.


Asunto(s)
Brazo , Taichi Chuan , Aceleración , Brazo/fisiología , Fenómenos Biomecánicos , Humanos , Movimiento/fisiología
4.
Artículo en Inglés | MEDLINE | ID: mdl-34898436

RESUMEN

Cervical spinal cord injuries frequently cause paralysis of all four limbs - a medical condition known as tetraplegia. Functional electrical stimulation (FES), when combined with an appropriate controller, can be used to restore motor function by electrically stimulating the neuromuscular system. Previous works have demonstrated that reinforcement learning can be used to successfully train FES controllers. Here, we demonstrate that transfer learning and curriculum learning can be used to improve the learning rates, accuracies, and workspaces of FES controllers that are trained using reinforcement learning.


Asunto(s)
Terapia por Estimulación Eléctrica , Traumatismos de la Médula Espinal , Brazo/fisiología , Humanos , Músculo Esquelético/fisiología , Cuadriplejía
5.
PLoS One ; 15(11): e0242552, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33211773

RESUMEN

Restoration of upper limb motor function and patient functional independence are crucial treatment targets in neurological rehabilitation. Growing evidence indicates that music-based intervention is a promising therapeutic approach for the restoration of upper extremity functional abilities in neurologic conditions such as cerebral palsy, stroke, and Parkinson's Disease. In this context, music technology may be particularly useful to increase the availability and accessibility of music-based therapy and assist therapists in the implementation and assessment of targeted therapeutic goals. In the present study, we conducted a pre-clinical, single-arm trial to evaluate a novel music-based therapeutic device (SONATA) for upper limb extremity movement training. The device consists of a graphical user interface generated by a single-board computer displayed on a 32" touchscreen with built-in speakers controlled wirelessly by a computer tablet. The system includes two operational modes that allow users to play musical melodies on a virtual keyboard or draw figures/shapes whereby every action input results in controllable sensory feedback. Four motor tasks involving hand/finger movement were performed with 21 healthy individuals (13 males, aged 26.4 ± 3.5 years) to evaluate the device's operational modes and main features. The results of the functional tests suggest that the device is a reliable system to present pre-defined sequences of audiovisual stimuli and shapes and to record response and movement data. This preliminary study also suggests that the device is feasible and adequate for use with healthy individuals. These findings open new avenues for future clinical research to further investigate the feasibility and usability of the SONATA as a tool for upper extremity motor function training in neurological rehabilitation. Directions for future clinical research are discussed.


Asunto(s)
Brazo/fisiología , Retroalimentación Sensorial , Trastornos del Movimiento/rehabilitación , Musicoterapia/instrumentación , Enfermedades Neuromusculares/rehabilitación , Modalidades de Fisioterapia/instrumentación , Estimulación Acústica , Adulto , Sistemas de Computación , Estudios de Factibilidad , Femenino , Dedos/fisiología , Mano/fisiología , Humanos , Masculino , Trastornos del Movimiento/fisiopatología , Música , Enfermedades Neuromusculares/fisiopatología , Estimulación Luminosa , Desempeño Psicomotor , Tiempo de Reacción , Valores de Referencia , Conducta Espacial , Interfaz Usuario-Computador , Adulto Joven
6.
Hum Mov Sci ; 74: 102715, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33227568

RESUMEN

Falls contribute to injuries and reduced level of physical activity in older adults. During falls, the abrupt sensation of moving downward triggers a startle-like reaction that may interfere with protective response movements necessary to maintain balance. Startle reaction could be dampened by sensory pre-stimulation delivered immediately before a startling stimulus. This study investigated the neuromodulatory effects of pre-stimulation on postural/startle responses to drop perturbations of the standing support surface in relation to age. Ten younger and 10 older adults stood quietly on an elevated computer-controlled moveable platform. At an unpredictable time, participants were dropped vertically to elicit a startle-like response. Reactive drop perturbation trials without a pre-stimulus (control) were alternated with trials with acoustic pre-stimulus tone (PSI). A two-way mixed design analysis of variance comparing condition (control vs. PSI) X group (younger vs. older) was performed to analyze changes in muscle activation patterns, ground reaction force, and joint angular displacements. Compared to younger adults, older adults showed lower neck muscle electromyography amplitude reduction rate and incidence of response. Peak muscle activation in neck, upper arm, and hamstring muscles were reduced during PSI trials compared to control trials in both groups (p < 0.05). In addition, knee and hip joint flexion prior to ground contact was reduced in PSI trials compared to control (p < 0.05). During post-landing balance recovery, increased knee and hip flexion displacement and time to peak impact force were observed in PSI trials compared to control condition (p < 0.05). PSI reduced startle-induced muscle activation at proximal body segments and likely decreased joint flexion during abrupt downward vertical displacement perturbations of the body. Older adults retained the ability to modulate startle and postural responses but their neuromodulatory capacity was reduced compared with younger adults. Further research on the potential of applying PSI as a possible therapeutic tool to reduce the risk of fall-related injury is needed.


Asunto(s)
Estimulación Acústica , Envejecimiento/fisiología , Equilibrio Postural/fisiología , Reflejo de Sobresalto/fisiología , Posición de Pie , Adulto , Anciano , Brazo/fisiología , Fenómenos Biomecánicos , Electromiografía , Femenino , Humanos , Articulaciones/fisiología , Pierna/fisiología , Masculino , Músculo Esquelético/fisiología , Músculos del Cuello/fisiología , Adulto Joven
7.
Eur J Appl Physiol ; 120(12): 2657-2664, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32892320

RESUMEN

PURPOSE: Spirulina has previously been reported to improve high-intensity exercise performance and hemoglobin. However, spirulina's effect on arm cycling exercise has yet to be investigated. The purpose of this study was to investigate the responses of spirulina supplementation on hemoglobin and on oxygen uptake, RER and HR during seated arm cycling exercise. METHODS: In a double-blinded randomized crossover design, eleven males untrained in arm cycling ingested 6 g/day of spirulina or placebo for seven days. Seated on the Arm Crank Ergometer, each participant performed a baseline V̇O2max test, and then after supplementation, 2 × 30-min submaximal exercise bouts corresponding to 55% of their V̇O2max, followed by an incremental test to fatigue. A seven-day wash-out period was required between conditions. Oxygen uptake, RER and HR were measured continuously during exercise and hemoglobin measured prior to exercise after both conditions. RESULTS: Spirulina significantly (p < 0.05) increased Hb in comparison to Placebo (144.1 g/l ± 10.5 Vs 154.5 g/l ± 6.9). After spirulina supplementation, during the 30-min exercise bouts, oxygen uptake and HR were significantly lower (2170 ml/min ± 173 Vs 2311 ml/min ± 189 and 154 bpm ± 14 Vs 149 bpm ± 17), RER was not significantly different. In comparison to placebo, Spirulina significantly increased oxygen uptake at time of fatigue (34.10 ml/min/kg ± 6.03 Vs 37.37 ml/min/kg ± 5.98). Time taken to fatigue was not different. CONCLUSION: Spirulina supplementation significantly reduces oxygen uptake and HR during arm cycling submaximal exercise, allowing for an increased oxygen uptake during an incremental test to fatigue.


Asunto(s)
Brazo/fisiología , Ejercicio Físico/fisiología , Consumo de Oxígeno/efectos de los fármacos , Oxígeno/metabolismo , Spirulina/química , Adulto , Estudios Cruzados , Suplementos Dietéticos , Método Doble Ciego , Fatiga/fisiopatología , Frecuencia Cardíaca/efectos de los fármacos , Humanos , Masculino , Adulto Joven
8.
J Manipulative Physiol Ther ; 43(4): 276-283, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32723666

RESUMEN

OBJECTIVE: The aim of this study was to assess the between-day reliability of the scapular locator for measuring scapular rotations during arm elevation in patients without shoulder pain/conditions/disorders. METHODS: Twenty-three asymptomatic individuals were measured during 2 sessions separated by 24 hours. One observer measured scapular position with a scapular locator while participants held their arms at 30°, 60°, 90°, and 120° elevation in the scapular plane. Three trials were performed for each arm position. RESULTS: At 30°, between-day intraclass correlation coefficients (ICCs) for all scapular rotations were poor (ICC 0.10-0.40). At higher arm elevations (60°, 90°, and 120°), ICCs ranged from 0.73 to 0.93 for scapular upward rotation, 0.80 to 0.87 for posterior tilt, and 0.37 to 0.62 for scapular internal rotation. For all scapular rotations, the standard error of measurement was less than 6°, and the smallest detectable difference ranged from 11° to 18°. CONCLUSION: The findings indicate good to excellent reliability for measuring scapular upward/downward rotation and anterior/posterior tilt between 60° and 120° of shoulder elevation in the scapular plane. However, low reliability was found for all scapular rotations at 30° elevation, and for scapular internal rotation at higher arm elevation.


Asunto(s)
Brazo/fisiología , Escápula/fisiología , Articulación del Hombro/fisiología , Adulto , Fenómenos Biomecánicos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Hombro
9.
J Bodyw Mov Ther ; 24(1): 263-268, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31987555

RESUMEN

INTRODUCTION: The purpose of this study was to investigate the effect of different rest intervals within paired sets (PS) on total work and training volume, efficiency (training volume load/session duration time), and myoelectric activity. METHOD: Fifteen trained men participated in this study. Four experimental protocols were applied: P30 (30 s rest), P60 (60 s rest), P90 (90 s rest), and P120 (120 s rest). The PS bout consisted of a bench press (BP)/lat pull down (LPD), 30° incline bench press (BP30)/wide-grip seated row (SR), and triceps extension (TE)/biceps curl (BC) exercises. Surface electromyography (sEMG) activity of the biceps and triceps brachii were recorded. RESULTS: Volume load (repetitions x number of exercise sets x loads) was significantly lower for the P30 (5385.8 ±â€¯1224 kg) versus the P60 (6755.6 ±â€¯1398.5 kg), P90 (7358.3 ±â€¯1490.3 kg), and P120 (7463 ±â€¯1310 kg) protocols. No significant differences in sEMG activity was noted between protocols. The efficiency (kg·min-1) of P30 (633.6 ±â€¯144) was significantly higher versus P60 (397.4 ±â€¯82.2), P90 (288.5 ±â€¯58.4), and P120 (219.5 ±â€¯38.5). CONCLUSION: Short intra-set rest intervals (60 s) within PS may be a potential alternative for increasing the volume load, since longer intra-rest (90 s and 120 s) intervals do not provide additional benefits.


Asunto(s)
Músculo Esquelético/fisiología , Entrenamiento de Fuerza/métodos , Descanso/fisiología , Adulto , Brazo/fisiología , Presión Sanguínea , Estudios Cruzados , Electromiografía , Frecuencia Cardíaca/fisiología , Humanos , Contracción Isométrica/fisiología , Masculino , Factores de Tiempo , Adulto Joven
10.
Nutr Cancer ; 72(1): 62-73, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31135225

RESUMEN

Background and Aims: Synbiotics found to be beneficial in breast cancer survivors (BCSs) through its antioxidant properties. The aim of this study was to assess the effects of synbiotic supplementation on edema volume and some oxidative markers among obese and overweight patients with BCRL.Method: This randomized double-blind, placebo-controlled trial was conducted on 88 overweight and obese BCSs aged 18-65 years. All the subjects were given a specified low-calorie diet (LCD) and were randomly assigned into two groups to intake 109 CFU/day synbiotic supplement (n = 44) or placebo (n = 44) for 10 wk. Edema volume and serum total antioxidant capacity (TAC), malondialdehyde (MDA), glutathione peroxidase (GPx), and superoxide dismutase (SOD) concentration were measured at baseline and after the 10-wk intervention.Results: Ten-wk supplementation with synbiotics leads to a significant reduction in serum MDA levels (P = 0.001) and an increase in serum SOD concentration (P = 0.007) compared to placebo. No significant changes were observed in serum GPx, TAC, and edema volume between groups.Conclusion: Our findings reveal that 10-wk synbiotic supplementation along with a LCD program-reduced serum MDA levels and elevate the activity of SOD in overweight and obese patients with BCRL. However, its effect on serum GPx, TAC, and edema volume was not significant.


Asunto(s)
Antioxidantes/metabolismo , Brazo/fisiología , Neoplasias de la Mama/complicaciones , Supervivientes de Cáncer/estadística & datos numéricos , Linfedema/dietoterapia , Estrés Oxidativo/fisiología , Simbióticos/administración & dosificación , Adolescente , Adulto , Biomarcadores/sangre , Neoplasias de la Mama/patología , Proteína C-Reactiva/metabolismo , Restricción Calórica/normas , Suplementos Dietéticos , Método Doble Ciego , Femenino , Humanos , Linfedema/etiología , Linfedema/patología , Malondialdehído/sangre , Persona de Mediana Edad , Superóxido Dismutasa-1/sangre , Adulto Joven
11.
J Neural Eng ; 17(1): 016064, 2020 02 18.
Artículo en Inglés | MEDLINE | ID: mdl-31791027

RESUMEN

OBJECTIVE: Neuromuscular electrical stimulation can help activate muscles of individuals with neurological disorders. However, conventional electrical stimulation targets distal branches of motor axons, and activates muscles non-physiologically. For example, stimulation at the muscle belly activates muscles in a highly synchronized manner. Accordingly, we investigated whether the muscle activation pattern was more asynchronized through transcutaneous stimulation near the cervical spinal cord (tsCSC). APPROACH: A stimulation array was placed on the posterior side near the cervical spinal cord, to target the arm and hand muscles. Stimulation trains of 10 Hz and 30 Hz were delivered. Electromyogram signals were recorded to quantify the muscle activation patterns. Arm and finger joint kinematics were also recorded using a motion capture system. MAIN RESULTS: After an initial synchronized activation prior to 35 ms after stimulation onset, we observed substantial asynchronized muscle activities with a long latency (>35 ms). The asynchronized activation is also more evident in distal muscles compared with the proximal muscles. In addition, the decreased synchronization level of muscle activities correlated with a reduced fluctuation of joint movement. The highly asynchronized muscle activities indicated an activation of the sensory axons and/or dorsal roots as well as a possible involvement of some spinal-supraspinal circuitry. SIGNIFICANCE: Our tsCSC approach can improve the muscle activation pattern during electrical stimulation with a possible involvement of the spinal and supraspinal pathways, which can facilitate applications on rehabilitation/assistance of individuals with impaired motor function.


Asunto(s)
Médula Cervical/fisiología , Electromiografía/métodos , Contracción Muscular/fisiología , Músculo Esquelético/inervación , Músculo Esquelético/fisiología , Estimulación Eléctrica Transcutánea del Nervio/métodos , Adulto , Brazo/inervación , Brazo/fisiología , Humanos , Masculino , Adulto Joven
12.
Sensors (Basel) ; 19(23)2019 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-31771131

RESUMEN

Currently, with the satisfaction of people's material life, sports, like yoga and tai chi, have become essential activities in people's daily life. For most yoga amateurs, they could only learn yoga by self-study, like mechanically imitating from yoga video. They could not know whether they performed standardly without feedback and guidance. In this paper, we proposed a full-body posture modeling and quantitative evaluation method to recognize and evaluate yoga postures to provide guidance to the learner. Back propagation artificial neural network (BP-ANN) was adopted as the first classifier to divide yoga postures into different categories, and fuzzy C-means (FCM) was utilized as the second classifier to classify the postures in a category. The posture data on each body part was regarded as a multidimensional Gaussian variable to build a Bayesian network. The conditional probability of the Gaussian variable corresponding to each body part relative to the Gaussian variable corresponding to the connected body part was used as criterion to quantitatively evaluate the standard degree of body parts. The angular differences between nonstandard parts and the standard model could be calculated to provide guidance with an easily-accepted language, such as "lift up your left arm", "straighten your right forearm". To evaluate our method, a wearable device with 11 inertial measurement units (IMUs) fixed onto the body was designed to measure yoga posture data with quaternion format, and the posture database with a total of 211,643 data frames and 1831 posture instances was collected from 11 subjects. Both the posture recognition test and evaluation test were conducted. In the recognition test, 30% data was randomly picked from the database to train BP-ANN and FCM classifiers, and the recognition accuracy of the remaining 70% data was 95.39%, which is highly competitive with previous posture recognition approaches. In the evaluation test, 30% data were picked randomly from subject three, subject four, and subject six, to train the Bayesian network. The probabilities of nonstandard parts were almost all smaller than 0.3, while the probabilities of standard parts were almost all greater than 0.5, and thus the nonstandard parts of body posture could be effectively separated and picked for guidance. We also tested separately the trainers' yoga posture performance in the condition of without and with guidance provided by our proposed method. The results showed that with guidance, the joint angle errors significantly decreased.


Asunto(s)
Monitoreo Ambulatorio/instrumentación , Postura/fisiología , Adulto , Algoritmos , Brazo/fisiología , Teorema de Bayes , Fenómenos Biomecánicos/fisiología , Estudios de Evaluación como Asunto , Retroalimentación , Femenino , Humanos , Masculino , Movimiento/fisiología , Redes Neurales de la Computación , Dispositivos Electrónicos Vestibles , Yoga , Adulto Joven
13.
J Neural Eng ; 17(1): 016002, 2019 12 05.
Artículo en Inglés | MEDLINE | ID: mdl-31610530

RESUMEN

OBJECTIVE: Haptic feedback is crucial when we manipulate objects. Information pertaining to an object's stiffness in particular can help facilitate fine motor control. In this study, we seek to determine whether objects of different stiffness levels can be recognized using haptic feedback provided by transcutaneous electrical stimulation of peripheral nerves. APPROACH: Using a stimulation electrode grid placed along the medial side of the upper arm, the median and ulnar nerve bundles were targeted to evoke haptic sensation on the palmar side of the hand. Stimulation current amplitude was modulated in real-time with the fingertip force recorded from a sensorized prosthetic hand. In order to evaluate which stimulation pattern was more critical, object stiffness was encoded either by the rate of change of the stimulus amplitude or the level of peak stimulus amplitude, as the prosthesis grasped the objects. MAIN RESULTS: Both encoding methods allowed the subjects to differentiate objects of different stiffness levels with >90% accuracy. No significant difference was observed between the two encoding methods, which indicated that both the rate of change of the stimulation amplitude and the peak stimulation amplitude could effectively provide stiffness information of the objects. SIGNIFICANCE: The outcomes suggest that it is possible to elicit haptic sensations describing various object stiffness levels using transcutaneous nerve stimulation. The haptic feedback associated with object stiffness can facilitate object manipulation/interactions. It may also improve user experience during human-machine interactions, when object stiffness information is incorporated.


Asunto(s)
Miembros Artificiales , Retroalimentación Sensorial/fisiología , Nervio Mediano/fisiología , Percepción del Tacto/fisiología , Estimulación Eléctrica Transcutánea del Nervio/métodos , Nervio Cubital/fisiología , Adulto , Brazo/inervación , Brazo/fisiología , Femenino , Humanos , Masculino , Adulto Joven
14.
IEEE Int Conf Rehabil Robot ; 2019: 1153-1158, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31374785

RESUMEN

Individuals with paralyzed limbs due to spinal cord injuries lack the ability to perform the reaching motions necessary to every day life. Functional electrical stimulation (FES) is a promising technology for restoring reaching movements to these individuals by reanimating their paralyzed muscles. We have proposed using a quasi-static model-based control strategy to achieve reaching controlled by FES. This method uses a series of static positions to connect the starting wrist position to the goal. As a first step to implementing this controller, we have completed a simulated study using a MATLAB based dynamic model of the arm in order to determine the suitable parameters for the quasi-static controller. The selected distance between static positions in the path was 6 cm, and the amount of time between switching target positions was 1.3 s. The final controller can complete reaches of over 30 cm with a median accuracy of 6.8 cm.


Asunto(s)
Brazo/fisiología , Parálisis/terapia , Muñeca/fisiología , Terapia por Estimulación Eléctrica , Humanos , Músculo Esquelético/fisiología , Traumatismos de la Médula Espinal/fisiopatología
15.
Neuroscience ; 418: 82-95, 2019 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-31442568

RESUMEN

Action observation (AO) alone or combined with motor imagery (AO + MI) has been shown to engage the motor system. While recent findings support the potential relevance of both techniques to enhance muscle function, this issue has received limited scientific scrutiny. In the present study, we implemented a counterbalanced conditions design where 21 participants performed 10 maximal isometric contractions (12-s duration) of elbow flexor muscles against a force platform. During the inter-trial rest periods, participants completed i) AO of the same task performed by an expert athlete, ii) AO + MI, i.e. observation of an expert athlete while concurrently imagining oneself performing the same task, and iii) watching passively a video documentary about basketball shooting (Control). During force trials, we recorded the total force and integrated electromyograms from the biceps brachii and anterior deltoideus. We also measured skin conductance from two finger electrodes as an index of sympathetic nervous system activity. Both AO and AO + MI outperformed the Control condition in terms of total force (2.79-3.68%, p < 0.001). For all conditions, we recorded a positive relationship between the biceps brachii activation and the total force developed during the task. However, only during AO was a positive relationship observed between the activation of the anterior deltoideus and the total force. We interpreted the results with reference to the statements of the psycho-neuromuscular theory of mental practice. Present findings extend current knowledge regarding the priming effects of AO and AO + MI on muscle function, and may contribute to the optimization of training programs in sports and rehabilitation.


Asunto(s)
Imaginación/fisiología , Contracción Isométrica/fisiología , Actividad Motora/fisiología , Músculo Esquelético/fisiología , Adulto , Brazo/fisiología , Articulación del Codo/fisiología , Electromiografía/métodos , Femenino , Humanos , Masculino
16.
Medicine (Baltimore) ; 97(43): e12922, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30412097

RESUMEN

This study compared muscle oxygenation (StO2) during arm cranking (ACE), functional electrical stimulation-evoked leg cycling (FES-LCE), and hybrid (ACE+FES-LCE) exercise in spinal cord injury individuals. Eight subjects with C7-T12 lesions performed exercises at 3 submaximal intensities. StO2 was measured during rest and exercise at 40%, 60%, and 80% of subjects' oxygen uptake (VO2) peak using near-infrared spectroscopy. StO2 of ACE showed a decrease whereas in ACE+FES-LCE, the arm muscles demonstrated increasing StO2 from rest in all of VO2) peak respectively. StO2 of FES-LCE displayed a decrease at 40% VO2 peak and steady increase for 60% and 80%, whereas ACE+FES-LCE revealed a steady increase from rest at all VO2 peak. ACE+FES-LCE elicited greater StO2 in both limbs which suggested that during this exercise, upper- and lower-limb muscles have higher blood flow and improved oxygenation compared to ACE or FES-LCE performed alone.


Asunto(s)
Brazo/fisiología , Pierna/fisiología , Músculos/metabolismo , Consumo de Oxígeno/fisiología , Traumatismos de la Médula Espinal/rehabilitación , Adulto , Brazo/irrigación sanguínea , Terapia por Estimulación Eléctrica/métodos , Ejercicio Físico/fisiología , Prueba de Esfuerzo/métodos , Humanos , Pierna/irrigación sanguínea , Extremidad Inferior/fisiopatología , Masculino , Espectroscopía Infrarroja Corta/métodos , Traumatismos de la Médula Espinal/fisiopatología
17.
Complement Ther Med ; 40: 191-194, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30219447

RESUMEN

INTRODUCTION: Raynaud's phenomenon is the earliest manifestation of systemic sclerosis. Nitroglycerin gel is the only proven topical therapy. METHODS: A 53-year-old woman with systemic sclerosis had topical Rosamarinus officinalis (rosemary) oil, often used in anthroposophic medicine, applied to her hands over 3days and then, separately, olive oil. RESULTS: Thermography images showed significant warming of fingers after rosemary oil, but not after olive oil, coinciding with the patient's subjective experience. CONCLUSIONS: Topical Rosamarinus officinalis oil had a vasodilator and warming effect in a patient with systemic sclerosis and Raynaud's phenomenon.


Asunto(s)
Aceites Volátiles/uso terapéutico , Enfermedad de Raynaud/tratamiento farmacológico , Enfermedad de Raynaud/etiología , Esclerodermia Sistémica/complicaciones , Brazo/fisiología , Femenino , Humanos , Persona de Mediana Edad , Termografía
18.
Pediatrics ; 142(3)2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30143567

RESUMEN

BACKGROUND: In moderate acute malnutrition programs, it is common practice to not measure mid-upper arm circumference (MUAC) of children whose length is <67 cm. This is based on expert opinion that supplementation of shorter children with low MUAC and weight-for-height z score ≥-2 may increase risk of excessive fat accumulation. Our aim was to assess if shorter children gain more fat than taller children when treated for moderate acute malnutrition diagnosed by low MUAC alone. METHODS: In this observational study, we included children aged 6 to 23 months with a MUAC between 115 and 125 mm and a weight-for-height z score ≥-2. On the basis of length at admission, children were categorized as short if <67 cm and long if ≥67 cm. Linear mixed-effects models were used to assess body composition on the basis of deuterium dilution and skinfold thickness. RESULTS: After 12 weeks of supplementation, there was no difference in change in fat mass index (-0.038 kg/m2, 95% confidence interval [CI]: -0.257 to 0.181, P = .74) or fat-free mass index (0.061 kg/m2, 95% CI: -0.150 to 0.271, P = .57) in short versus long. In absolute terms, the short children gained both less fat-free mass (-230 g, 95% CI: -355 to -106, P < .001) and fat mass (-97 g, 95% CI: -205 to 10, P = .076). There was no difference in changes in absolute subscapular and triceps skinfold thickness and z scores (P > .5). CONCLUSIONS: Short children with low MUAC do not gain excessive fat during supplementation. With these data, we support a recommendation for policy change to include all children ≥6 months with low MUAC in supplementary feeding programs, regardless of length. The use of length as a criterion for measuring MUAC to determine treatment eligibility should be discontinued in policy and practice.


Asunto(s)
Tejido Adiposo/fisiopatología , Composición Corporal/fisiología , Suplementos Dietéticos/efectos adversos , Trastornos de la Nutrición del Lactante/diagnóstico , Brazo/fisiología , Estatura/fisiología , Peso Corporal , Burkina Faso , Estudios de Cohortes , Femenino , Humanos , Lactante , Trastornos de la Nutrición del Lactante/fisiopatología , Trastornos de la Nutrición del Lactante/terapia , Fenómenos Fisiológicos Nutricionales del Lactante , Masculino , Estudios Prospectivos
19.
Sci Rep ; 8(1): 10583, 2018 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-30002452

RESUMEN

Motor deficit is among the most debilitating aspects of injury to the central nervous system. Despite ongoing progress in brain-machine interface (BMI) development and in the functional electrical stimulation of muscles and nerves, little is understood about how neural signals in the brain may be used to potentially control movement in one's own unconstrained paralyzed limb. We recorded from high-density electrocorticography (ECoG) electrode arrays in the ventral premotor cortex (PMv) of a rhesus macaque and used real-time motion tracking techniques to correlate spatial-temporal changes in neural activity with arm movements made towards objects in three-dimensional space at millisecond precision. We found that neural activity from a small number of electrodes within the PMv can be used to accurately predict reach-return movement onset and directionality. Also, whereas higher gamma frequency field activity was more predictive about movement direction during performance, mid-band (beta and low gamma) activity was more predictive of movement prior to onset. We speculate these dual spatiotemporal signals may be used to optimize both planning and execution of movement during natural reaching, with prospective relevance to the future development of neural prosthetics aimed at restoring motor control over one's own paralyzed limb.


Asunto(s)
Brazo/fisiología , Interfaces Cerebro-Computador , Corteza Motora/fisiología , Movimiento/fisiología , Animales , Brazo/inervación , Conducta Animal/fisiología , Terapia por Estimulación Eléctrica/métodos , Electrocorticografía/instrumentación , Electrodos Implantados , Macaca mulatta , Masculino , Modelos Animales , Parálisis/rehabilitación
20.
Folia Med (Plovdiv) ; 60(1): 158-163, 2018 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-29668461

RESUMEN

Mobilization and Stimulation of Neuromuscular Tissue (MASONT) is a newly invented somatosensory intervention used for the recovery of function in stroke patients. This paper aims to offer a more spherical view on the new technique. To that end, a basic manual of MASONT's application is provided, along with its rational of use. Moreover, clinical observations on the application of the technique and its effects on neurological patients are presented, as well as, a report on its safety.


Asunto(s)
Músculo Esquelético , Manipulaciones Musculoesqueléticas/métodos , Rehabilitación de Accidente Cerebrovascular/métodos , Anciano , Brazo/inervación , Brazo/fisiología , Femenino , Humanos , Masculino , Músculo Esquelético/inervación , Músculo Esquelético/fisiología
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