title: Intermuscular pressure between synergistic muscles correlates with muscle force.
abstract: The purpose of the study was to examine the relationship between muscle force generated during isometric contractions (i.e. at a constant muscle-tendon unit length) and the intermuscular (between adjacent muscles) pressure in synergistic muscles. Therefore, the pressure at the contact area of the gastrocnemius and plantaris muscle was measured synchronously to the force of the whole calf musculature in the rabbit species Oryctolagus cuniculus Similar results were obtained when using a conductive pressure sensor, or a fibre-optic pressure transducer connected to a water-filled balloon. Both methods revealed a strong linear relationship between force and pressure in the ascending limb of the force-length relationship. The shape of the measured force-time and pressure-time traces was almost identical for each contraction (r=0.97). Intermuscular pressure ranged between 100 and 700 mbar (70,000 Pa) for forces up to 287 N. These pressures are similar to previous (intramuscular) recordings within skeletal muscles of different vertebrate species. Furthermore, our results suggest that the rise in intermuscular pressure during contraction may reduce the force production in muscle packages (compartments).
authors.affiliation: Science of Motion, Friedrich-Schiller-University Jena, Seidelstr. 20, Jena D-07749, Germany lars.reinhardt@uni-jena.de.
authors.forename: Lars
authors.identifier: 0000-0001-5054-5592
authors.initials: L
authors.lastname: Reinhardt
authors.affiliation: Institute of Sport and Motion Science, University of Stuttgart, Allmandring 28, Stuttgart D-70569, Germany.
authors.forename: Tobias
authors.initials: T
authors.lastname: Siebert
authors.affiliation: Institute of Solid Mechanics, Technical University Braunschweig, Schleinitzstr. 20, Braunschweig D-38106, Germany.
authors.forename: Kay
authors.initials: K
authors.lastname: Leichsenring
authors.affiliation: Science of Motion, Friedrich-Schiller-University Jena, Seidelstr. 20, Jena D-07749, Germany.
authors.forename: Reinhard
authors.initials: R
authors.lastname: Blickhan
authors.affiliation: Institute of Solid Mechanics, Technical University Braunschweig, Schleinitzstr. 20, Braunschweig D-38106, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Böl
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D007537:Isometric Contraction / Q000502:physiology; D016014:Linear Models; D008954:Models, Biological; D009132:Muscles / Q000502:physiology*; D011312:Pressure; D011817:Rabbits; D013997:Time Factors; D014159:Transducers
keywords: Calf muscles; Isometric contraction; Muscle compression; Oryctolagus cuniculus; Transversal muscle loading