title: Torque-velocity and power-velocity relationships during isokinetic trunk flexion and extension.
abstract: BACKGROUND
  No study has reported the possibility of establishing torque-velocity and power-velocity relationships for both flexor and extensor trunk muscles. The present study therefore sought to assess these relationships during isokinetic exercise.
  
  
  METHODS
  Nine healthy male subjects performed series of isokinetic trunk flexions and extensions at six different velocities ranging from 45 degrees s(-1) to 120 degrees s(-1). Trunk flexor and extensor muscles were, respectively, assessed on two separate days. All experiments used a Biodex dynamometer.
  
  
  RESULTS
  Torque-velocity relationships were significantly well described by a linear relationship for both trunk flexor (P<0.01; r=0.92-0.99) and extensor muscles (P<0.05; r=0.82-0.97) in all subjects. Power-velocity relationships exhibited a parabolic shape for all subjects (P<0.05; r=0.96-0.99) for both muscle groups.
  
  
  CONCLUSIONS
  Results showed that trunk muscle torque- and power-velocity relationships can be assessed during isokinetic exercise. The findings were in agreement with previous studies of lower and upper limbs. This kind of measurement can therefore be applied in assessing low-back pain patients during rehabilitation.
authors.affiliation: Laboratoire des Activités Physiques et Sportives, Département STAPS, Université du Maine, Faculté des Sciences, Avenue Olivier Messiaen, 72089 Le Mans Cedex 9, France. m_ripamonti@hotmail.com
authors.forename: Mickaël
authors.initials: M
authors.lastname: Ripamonti
authors.forename: Denis
authors.initials: D
authors.lastname: Colin
authors.forename: Abderrahmane
authors.initials: A
authors.lastname: Rahmani
mesh_terms: D001415:Back / Q000502:physiology*; D003198:Computer Simulation; D006801:Humans; D008297:Male; D008954:Models, Biological; D009068:Movement / Q000502:physiology*; D009119:Muscle Contraction / Q000502:physiology*; D018482:Muscle, Skeletal / Q000502:physiology*; D013909:Thorax / Q000502:physiology*