title: Neuromuscular adaptations to electrostimulation resistance training.
abstract: A combination of in vivo and in vitro analyses was performed to investigate muscular and neural adaptations of the weaker (nondominant) quadriceps femoris muscle of one healthy individual to short-term electrostimulation resistance training. The increase in maximal voluntary strength (+12%) was accompanied by neural (cross-education effect and increased muscle activation) and muscle adaptations (impairment of whole-muscle contractile properties). Significant changes in myosin heavy chain (MHC) isoforms relative content (+22% for MHC-2A and -28% for MHC-2X), single-fiber cross-sectional area (+27% for type 1 and +6% for type 2A muscle fibers), and specific tension of type 1 (+67%) but not type 2A fibers were also observed after training. Plastic changes in neural control confirm the possible involvement of both spinal and supraspinal structures to electrically evoked contractions. Changes at the single muscle fiber level induced by electrostimulation resistance training were significant and preferentially affected slow, type 1 fibers.
authors.affiliation: Schulthess Klinik, Lengghalde 2, 8008 Zürich, Switzerland.
authors.forename: Nicola A
authors.initials: NA
authors.lastname: Maffiuletti
authors.forename: Raphael
authors.initials: R
authors.lastname: Zory
authors.forename: Danilo
authors.initials: D
authors.lastname: Miotti
authors.forename: Maria A
authors.initials: MA
authors.lastname: Pellegrino
authors.forename: Marc
authors.initials: M
authors.lastname: Jubeau
authors.forename: Roberto
authors.initials: R
authors.lastname: Bottinelli
mesh_terms: D000222:Adaptation, Physiological; D000328:Adult; D001707:Biopsy, Needle; D004558:Electric Stimulation; D004576:Electromyography; D006801:Humans; D007537:Isometric Contraction; D008297:Male; D018656:Muscle Fibers, Fast-Twitch / Q000473:pathology; D018657:Muscle Fibers, Slow-Twitch / Q000473:pathology; D018482:Muscle, Skeletal / Q000294:innervation* / Q000378:metabolism* / Q000473:pathology; D018995:Myosin Heavy Chains / Q000378:metabolism; D010806:Physical Education and Training / Q000379:methods*; D020033:Protein Isoforms / Q000378:metabolism; D019415:Torque
chemical_list: D020033:Protein Isoforms; D018995:Myosin Heavy Chains