Search results for "velocity"

Leg extension power asymmetry and mobility limitation in healthy older women

2005

Objective To investigate the association of asymmetry in leg extension power (LEP) with walking and standing balance. Design Cross-sectional analysis. Setting Research laboratory. Participants Healthy female twins (N=419), ages 63 to 75 years. Interventions Not applicable. Main Outcome Measures The LEP difference between the stronger and the weaker leg, measured with the Nottingham power rig, was calculated. Ten-meter maximal walking velocity was assessed in a laboratory corridor on a wide (170cm) and narrow (35cm) track, and the ability to maintain tandem stance for 20 seconds was recorded. Results The mean LEP difference ± standard deviation between the legs was 15%±9% (P<.001). Those wit…

Muscle conduction velocity, strength, neural activity, and morphological changes after eccentric and concentric training

2014

This study compared the effects of concentric and eccentric training on neuromuscular adaptations in young subjects. Twenty-two men and women were assigned to one of two groups: concentric (CON, n = 11) and eccentric (ECC, n = 11) training. Training consisted of 6 weeks of isokinetic exercise, performed twice weekly, starting with two sets of eight repetitions, and progressing to five sets of 10 repetitions. Subjects were tested in strength variables [concentric, eccentric, and isometric peak torque (PT), and rate of force development (RFD)], muscle conduction velocity (CV), neuromuscular activity, vastus lateralis (VL) muscle thickness, and echo intensity as determined by ultrasonography. …

Myoedema

1992

Stationary muscle mounding after muscle percussion without electrical muscle activity is called myoedema. Out of 105 patients with different neurological diseases, 88% had this phenomenon. Muscle conduction velocity and stimulated single fiber EMG disclosed no abnormalities. Myoedema is a normal physiological phenomenon, and its presence does not indicate a neuromuscular disorder.

A Velocity Estimation Technique for a Monocular Camera Using mmWave FMCW Radars

2021

Perception in terms of object detection, classification, and dynamic estimation (position and velocity) are fundamental functionalities that autonomous agents (unmanned ground vehicles, unmanned aerial vehicles, or robots) have to navigate safely and autonomously. To date, various sensors have been used individually or in combination to achieve this goal. In this paper, we present a novel method for leveraging millimeter wave radar’s (mmW radar’s) ability to accurately measure position and velocity in order to improve and optimize velocity estimation using a monocular camera (using optical flow) and machine learning techniques. The proposed method eliminates ambiguity in optical flow veloci…

Constant Power Model in Arm Rotation—A New Approach to Hill’s Equation

2014

The purpose of this study was to further develop the constant power model of a previous study and to provide the final solution of Hill’s force-velocity equation. Forearm and whole arm rotations of three different subjects were performed downwards (elbow and shoulder extension) and upwards (elbow and shoulder flexion) with maximum velocity. These arm rotations were recorded with a special camera system and the theoretically derived model of constant maximum power was fitted to the experimentally measured data. The moment of inertia of the arm sectors was calculated using immersion technique for determining accurate values of friction coefficients of elbow and whole arm rotations. The experi…

Modeling the force – velocity relationship in arm movement

2012

Modeling the force-velocity dependence of a muscle-tendon unit has been one of the most interesting objectives in the field of muscle mechanics. The so-called Hill’s equation [1,2] is widely used to describe the force-velocity relationship of muscle fibers. Hill’s equation was based on the laboratory measurements of muscle fibers and its application to the practical measurements in muscle mechanics has been problematic. Therefore, the purpose of this study was to develop a new explicit calculation method to determine the force-velocity relationship, and test its function in experimental measurements. The model was based on the motion analysis of arm movements. Experiments on forearm rotatio…

Modeling muscle mechanics of arm and leg movement : a new approach to Hill's equation

2015

M-mode Ultrasound Examination of Soleus Muscle in Healthy Subjects: Intra- and Inter-Rater Reliability Study

2020

Objective: M-mode ultrasound imaging (US) reflects the motion of connective tissue within muscles. The objectives of this study were to evaluate inter-rater and intra-rater reliability of soleus muscle measurements between examiners with different levels of US experience in asymptomatic subjects and to investigate the level of soleus muscle isometric activity in two positions (knee extended and knee flexed at 30&deg

Hill’s Equation in Arm Push of Shot Put and in Braking of Arm Rotation

2019

This chapter consists of the earlier study of shot put where A.V. Hill’s force-velocity relationship was transformed into a constant maximum power model consisting of three different components of power. In addition, the braking phase of the arm rotation movement was examined where Hill’s equation was applied for accelerated motions. Hill’s force-velocity relationship was tested by fitting it into two arm push measurements of shot put experiments and one braking phase of whole arm rotation. Theoretically derived equation for accelerated motions was in agreement with the measured data of shot put experiments and the braking phase of the whole arm rotation experiment. Maximum power in these e…

Gaia-ESO Survey: Cha I members

2017

Investigating the physical mechanisms driving the dynamical evolution of young star clusters is fundamental to our understanding of the star formation process and the properties of the Galactic field stars. The young (~2Myr) and partially embedded cluster Chamaeleon I is one of the closest laboratories to study the early stages of star cluster dynamics in a low-density environment. The aim of this work is to study the structural and kinematical properties of this cluster combining parameters from the high-resolution spectroscopic observations of the Gaia-ESO Survey with data from the literature. Our main result is the evidence of a large discrepancy between the velocity dispersion ({sigma}_…