Open AccessModeling the Force-Velocity Relationship in Arm
Author(s) -
Ahti Rahikainen,
Janne Avela,
Mikko Virmavirta
Publication year - 2012
Publication title -
world journal of mechanics
Language(s) - English
Resource type - Journals
eISSN - 2160-0503
pISSN - 2160-049X
DOI - 10.4236/wjm.2012.22011
Subject(s) - moment (physics) , mechanics , constant (computer programming) , physics , motion (physics) , angular velocity , dynamics (music) , movement (music) , equations of motion , mathematics , classical mechanics , power (physics) , mathematical analysis , computer science , thermodynamics , acoustics , programming language
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 rotations and whole arm rotations were performed downwards and upwards at maximum velocity. According to the present theory the movement proceeds as follows: start of motion, movement proceeds at constant maximum rotational moment (Hypothesis 1), movement proceeds at constant maximum power (Hypothesis 2), and stopping of motion. Theoretically derived equation, in which the motion proceeds at constant maximum power, fitted well the experimentally measured results. The constant maximum rotational moment hypothesis did not seem to fit the measured results and therefore a new equation which would better fit the measured results is needed for this hypothesis