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Fascial Manipulation®
Published in David Lesondak, Angeli Maun Akey, Fascia, Function, and Medical Applications, 2020
In FM, specific areas within the fascia of the MFU are identified and referred to as Centers of Coordination (CCs). The CC is the site where unidirectional forces or muscular vectors converge. It’s located between the deep fascia layers and it coordinates the action of unidirectional mono-articular and biarticular muscle fibers. It is the point where the vector forces act within each MFU. These are the points where FM treatment is performed. The CC points are specified by the six movement directions ante (an), retro (re), lateral (la), medial (me), external rotation (er), internal rotation (ir), and by the segment. For example, RE-CL refers to the point that functions in backward motion of the neck (CL = collum).
Conceptual Frameworks for Interpreting Motor Cortical Function: New Insights from a Planar Multiple-Joint Paradigm
Published in Alexa Riehle, Eilon Vaadia, Motor Cortex in Voluntary Movements, 2004
A key feature of both of these studies was that we could load the shoulder and elbow joints independently. It seems reasonable to assume that these single-joint loads would selectively influence the response of muscles that span that joint. We were mistaken. Many muscles that only spanned one of the two joints modified their activity for loads applied to the other joint. For example, brachioradialis, an elbow flexor muscle, increased its activity when the monkey generated either an elbow flexor or a shoulder extensor muscular torque (Figure 6.7). The greatest activity level was observed when the monkey generated an elbow flexor and a shoulder extensor torque simultaneously. At first, this seems paradoxical, but it simply reflects the action of biarticular muscles that span both joints. Changes in a biarticular muscle's activity for loads applied at one joint necessarily create torque at the other joint. As a result, the activity of muscles spanning this second joint must change to compensate for the change in activity of the biarticular muscles.7980
The Influence of Countermovements on Inter-Segmental Coordination and Mechanical Energy Transfer during Vertical Jumping
Published in Journal of Motor Behavior, 2021
Devon H. Frayne, John L. Zettel, Tyson A. C. Beach, Stephen H. M. Brown
Movement strategies during the propulsive phase of vertical jumping are sensitive to the mechanism by which elastic potential energy is delivered to the muscle tendon units during countermovements. Previous researchers found that when matched for external work demand, performing CMJs while wearing additional mass results in a higher contribution by the ankle relative to total limb work done compared to unloaded CMJs (Wade et al., 2018). The additional mass condition was thought to have elicited an increased storage of elastic potential energy in the Achilles tendon by way of larger gravitational forces and was associated with increased work done at the ankle. In a follow-up study using electromyography and ultrasound imaging techniques, the same authors observed longer periods of muscle activity and slowed fascicle shortening velocity of triceps surae muscles during loaded compared to unloaded jumps (Wade et al., 2019). When taken together, the results of both studies suggest that the timing and nature of muscle activity used during propulsion is sensitive to the source of elastic potential energy in muscle-tendon units. The authors also suggested that inter-segmental energy transferred via biarticular muscle-tendon units plays a role in the re-proportioning of mechanical work done by the lower limb joints (Wade et al., 2018). Uniarticular muscles possessing elastic tendons are also very much active during maximal vertical jumps and can additionally contribute to inter-segmental energy transfer (Bobbert & van Ingen Schenau, 1988).
The Influence of Contraction Types on the Relationship Between the Intended Force and the Actual Force
Published in Journal of Motor Behavior, 2020
Takeshi Miyamoto, Tomohiro Kizuka, Seiji Ono
The isometric force at the ankle joint in plantar flexion was measured using a customized dynamometer. This dynamometer consisted of a 15 × 30 cm footplate which is attached to a load cell transducer (LUR-A-1KNSA1; Kyowa Electronic Instruments, Tokyo, Japan). The reason for using the plantar flexion of the ankle joint was that there is no study to examine the relationship between the intended force and the actual force using the isometric plantar flexion, and the plantar flexion is comparable with dynamic movements such as jumping movements. The subjects were seated and their right thigh and ankle were fastened to the dynamometer. The knee and the ankle joint were placed at an angle of 90˚. The arms were folded across the chest during testing (Figure 1). The agonist for the ankle plantar flexion is the triceps surae (i.e., medial and lateral gastrocnemius and soleus). However, because the gastrocnemius is a biarticular muscle that acts both as a plantar flexor and a knee flexor, it is less involved in ankle plantar flexion when the knee is flexed 90˚. Therefore, EMG activity was recorded by surface electrodes (Bagnoli-2, Delsys, Boston, Massachusetts, USA) from the soleus of the right leg in this study. A reference electrode was placed over the head of fibula. Prior to application of electrodes, the skin was prepared using paste and alcohol to reduce skin impedance. The EMG signal was amplified 1000 times. The detected force and EMG signals were digitized at 1 kHz using Micro 1401-2 (Cambridge Electronic Design, Cambridge, UK) (Figure 2).
Toward bio-kinematic for secure use of rehabilitation exoskeleton
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2019
J. Charafeddine, D. Pradon, S. Alfayad, S. Chevallier, M. Khalil
Gait Laboratory (Raymond Poincaré Hospital, Garches, France). A bio-kinematics study was conducted in a large room; where the patients walked a straight line for 10 meters. The acquisition system includes:Video equipment to record the front and the profile of the patient.An optoelectronic system to measure the segment kinematics and the joint angles of the knee and the hip steps with respect to each foot (left and right).Ground force platforms to record dynamics (recording of ground reaction forces and the moments).An electromyographic system to record muscle activity. Electrodes were placed at the level of two biarticular muscle groups (quadriceps and hamstrings) for the knee and the hip on each leg (left and right). Everything was synchronized and connected to a computer for data acquisition. Kinematic measurements and electromyographic data were taken and recorded for three rhythms velocities (fast, normal and slow) and for 11 walking cycles at each velocity.