title: Effects of plyometric training on passive stiffness of gastrocnemii and the musculo-articular complex of the ankle joint.
abstract: This study aimed to determine simultaneously the effects of plyometric training on the passive stiffness of the ankle joint musculo-articular complex, the gastrocnemii muscle-tendon complex (MTC) and the Achilles tendon in order to assess possible local adaptations of elastic properties. Seventeen subjects were divided into a trained (TG) group and a control (CG) group. They were tested before and after 8 weeks of a plyometric training period. The ankle joint range of motion (RoM), the global musculo-articular passive stiffness of the ankle joint, the maximal passive stiffness of gastrocnemii and the stiffness of the Achilles tendon during isometric plantar flexion were determined. A significant increase in the jump performances of TG relative to CG was found (squat jumps: +17.6%, P=0.008; reactive jumps: +19.8%, P=0.001). No significant effect of plyometric training was observed in the ankle joint RoM, musculo-articular passive stiffness of the ankle joint or Achilles tendon stiffness (P>0.05). In contrast, the maximal passive stiffness of gastrocnemii of TG increased after plyometric training relative to CG (+33.3%, P=0.001). Thus, a specific adaptation of the gastrocnemii MTC occurred after plyometric training, without affecting the global passive musculo-articular stiffness of the ankle joint.
authors.affiliation: Laboratoire Motricité, Interactions, Performance- EA 4334, UFR STAPS, Université de Nantes, Nantes Atlantique Universités, Nantes, Cedex, France.
authors.forename: A
authors.initials: A
authors.lastname: Fouré
authors.forename: A
authors.initials: A
authors.lastname: Nordez
authors.forename: M
authors.initials: M
authors.lastname: Guette
authors.forename: C
authors.initials: C
authors.lastname: Cornu
mesh_terms: D000843:Ankle Joint / Q000503:physiopathology*; D001696:Biomechanical Phenomena; D006801:Humans; D007537:Isometric Contraction / Q000502:physiology*; D008297:Male; D018482:Muscle, Skeletal / Q000503:physiopathology*; D010865:Pilot Projects; D016059:Range of Motion, Articular; D016896:Treatment Outcome; D055815:Young Adult