title: Postcontraction changes of muscle architecture in human quadriceps muscle.
abstract: Maximal voluntary contraction changes the mechanical properties of skeletal muscle. Using ultrasound, we investigated whether these changes are reflected by changes in muscle architecture in the vastus lateralis muscle of 8 healthy volunteers. The mean pennation angle during the time interval from 3 to 6 min after maximal voluntary contraction (late postcontraction state) was 14.4 +/- 1.11 degrees (mean +/- SEM) and differed significantly from the precontraction state (16.2 +/- 1.39 degrees ), but the pennation angle in the early postcontraction state did not change statistically from the precontraction angle. Thus, postcontraction changes of the muscle-tendon interface appeared for 6 min after a maximal contraction, which may be important for biomechanical optimization of force transmission in vivo.
authors.affiliation: Department of Orthopaedics, Otto von Guericke University, Leipziger Strasse 44, 39120 Magdeburg, Germany. konrad.mahlfeld@medizin.uni-magdeburg.de
authors.forename: Konrad
authors.initials: K
authors.lastname: Mahlfeld
authors.forename: Jörg
authors.initials: J
authors.lastname: Franke
authors.forename: Friedemann
authors.initials: F
authors.lastname: Awiszus
mesh_terms: D000328:Adult; D001696:Biomechanical Phenomena; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007537:Isometric Contraction / Q000502:physiology; D007866:Leg / Q000033:anatomy & histology / Q000502:physiology; D008297:Male; D009119:Muscle Contraction / Q000502:physiology*; D018482:Muscle, Skeletal / Q000033:anatomy & histology* / Q000000981:diagnostic imaging / Q000502:physiology*; D014463:Ultrasonography