title: Comparison in responses to maximal eccentric exercise between elbow flexors and knee extensors of older adults.
abstract: OBJECTIVE
  To compare the susceptibility of elbow flexors (EF) and knee extensors (KE) to eccentric exercise-induced muscle damage in older individuals, since ageing could modulate the difference in the susceptibility to muscle damage between muscles.
  
  
  METHODS
  Cross-sectional and cross-over study design.
  
  
  METHODS
  Eight older (61.6 ± 1.8 years) adults performed 5 sets of 6 maximal isokinetic (90° s(-1)) eccentric contractions of the EF (range of motion: 80-20°) and KE (30-90°) with the non-dominant limb in a randomised, counterbalanced order with 2 weeks between bouts. Maximal voluntary isometric (MVC-ISO) and concentric contraction torque, optimum angle, range of motion (ROM), muscle soreness and serum creatine kinase (CK) activity were measured before, immediately after (except CK), and 24, 48, 72 and 96 h following exercise. Normalised changes in the variables following exercise were compared between EF and KE by a mixed model analysis of variance.
  
  
  RESULTS
  Only MVC-ISO and ROM demonstrated significant group effects (p<0.05) for the comparison between EF and KE. Additionally, no significant group vs. time interactions (p>0.05) were found between EF and KE for any of the dependent variables changes.
  
  
  CONCLUSIONS
  These results suggest that the KE of older adults are relatively as susceptible to muscle damage as their EF, or at the very least, the difference between EF and KE are small for older adults.
authors.affiliation: School of Physical Education, State University of Campinas, Brazil. Electronic address: felipedamasfl@gmail.com.
authors.forename: Felipe Romano Damas
authors.initials: FR
authors.lastname: Nogueira
authors.affiliation: School of Physical Education, State University of Campinas, Brazil; School of Physical Education and Sport, University of São Paulo, Brazil.
authors.forename: Cleiton Augusto
authors.initials: CA
authors.lastname: Libardi
authors.affiliation: School of Exercise and Health Sciences, Edith Cowan University, Australia.
authors.forename: Kazunori
authors.initials: K
authors.lastname: Nosaka
authors.affiliation: School of Physical Education, State University of Campinas, Brazil; School of Physical Education and Sport, University of São Paulo, Brazil.
authors.forename: Felipe Cassaro
authors.initials: FC
authors.lastname: Vechin
authors.affiliation: School of Physical Education, State University of Campinas, Brazil.
authors.forename: Claudia Regina
authors.initials: CR
authors.lastname: Cavaglieri
authors.affiliation: School of Physical Education, State University of Campinas, Brazil.
authors.forename: Mara Patricia Traina
authors.initials: MP
authors.lastname: Chacon-Mikahil
mesh_terms: D000375:Aging / Q000502:physiology*; D018592:Cross-Over Studies; D003430:Cross-Sectional Studies; D006801:Humans; D035002:Lower Extremity / Q000502:physiology*; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000502:physiology*; D055070:Resistance Training; D034941:Upper Extremity / Q000502:physiology*
keywords: Ageing; Creatine kinase; Delayed onset muscle soreness; Maximal voluntary isometric contraction; Muscle damage; Range of motion