title: Repeated bouts of fast eccentric contraction produce sciatic nerve damage in rats.
abstract: We evaluated sciatic nerve impairment after eccentric contractions (ECs) in rat triceps surae.
  
  
  
  Wistar rats were randomly assigned to different joint angular velocity: 180°/s (FAST), 30°/s (SLOW), or nontreated control (CNT). FAST and SLOW groups were subjected to multiple (1-4) bouts of 20 (5 reps, 4 sets) ECs. Nerve conduction velocity (NCV) and isometric tetanic ankle torque were measured 24 h after each ECs bout. We also assessed nerve morphology.
  
  
  
  After 4 ECs bouts, NCVs and isometric torque in the FAST group were significantly lower than those in the CNT (NCV: 42%, torque: 66%; P < 0.05). After 4 bouts, average nerve diameter was significantly smaller in the FAST group [2.39 ± 0.20 μm vs. 2.69 ± 0.20 μm (CNT) and 2.93 ± 0.24 μm (SLOW); P < 0.05] than that in other two groups.
  
  
  
  Chronic ECs with high angular velocity induce serious nerve damage. Muscle Nerve 54: 936-942, 2016.
authors.affiliation: Graduate School of Health and Sport Science, Nippon Sport Science University, 7-1-1, Fukasawa, Setagaya, Tokyo, 158-8508, Japan. kouzaki.karina@gmail.com.
authors.forename: Karina
authors.initials: K
authors.lastname: Kouzaki
authors.affiliation: Graduate School of Health and Sport Science, Nippon Sport Science University, 7-1-1, Fukasawa, Setagaya, Tokyo, 158-8508, Japan.
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Kobayashi
authors.affiliation: Division of Microscopic and Developmental Anatomy, Department of Anatomy, Kurume University School of Medicine, Kurume, Fukuoka, 830-0011, Japan.
authors.forename: Kei-Ichiro
authors.initials: KI
authors.lastname: Nakamura
authors.affiliation: Division of Microscopic and Developmental Anatomy, Department of Anatomy, Kurume University School of Medicine, Kurume, Fukuoka, 830-0011, Japan.
authors.forename: Keisuke
authors.initials: K
authors.lastname: Ohta
authors.affiliation: Graduate School of Health and Sport Science, Nippon Sport Science University, 7-1-1, Fukasawa, Setagaya, Tokyo, 158-8508, Japan.
authors.forename: Koichi
authors.identifier: 0000-0002-2479-5771
authors.initials: K
authors.lastname: Nakazato
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D000842:Ankle / Q000294:innervation; D001835:Body Weight; D004195:Disease Models, Animal; D007537:Isometric Contraction / Q000502:physiology*; D008297:Male; D008854:Microscopy, Electron; D018482:Muscle, Skeletal / Q000503:physiopathology* / Q000648:ultrastructure; D009186:Myelin Sheath / Q000473:pathology / Q000648:ultrastructure; D009412:Nerve Fibers / Q000473:pathology / Q000648:ultrastructure; D009431:Neural Conduction / Q000502:physiology; D009929:Organ Size; D051381:Rats; D017208:Rats, Wistar; D011930:Reaction Time / Q000502:physiology; D020426:Sciatic Neuropathy / Q000473:pathology* / Q000503:physiopathology; D019415:Torque
keywords: joint angle speed; muscle damage; muscular atrophy; myelin sheath thickness; nerve conduction impairment; nerve fiber diameter