title: Oxidative stress and inflammatory responses following an acute bout of isokinetic exercise in obese women with knee osteoarthritis.
abstract: BACKGROUND
  Obesity is associated with osteoarthritis and it is accompanied by chronic inflammation and elevated oxidative stress. Strengthening-type exercise is used in knee osteoarthritis (KOA) rehabilitation. This study determined how acute isokinetic exercise influences inflammatory responses of obese middle-aged women with KOA.
  
  
  METHODS
  Ten obese women with KOA and 10 age/weight-matched controls performed an isokinetic exercise protocol. Assessment of performance (knee extensor/flexor torque), muscle soreness (DOMS), knee flexibility (KJRM), and pain, and blood collection were performed pre-exercise, post-exercise, and at 24h post-exercise. Blood was analyzed for creatine kinase activity (CK), lactate dehydrogenase activity (LDH), CRP, leukocytes, uric acid, IL-6, TBARS, lipid hydroperoxides (LPX), protein carbonyls (PC), oxidized (GSH) and reduced glutathione (GSSG), total antioxidant capacity (TAC), catalase activity, and glutathione peroxidase activity (GPX).
  
  
  RESULTS
  Physical function remained unaltered by exercise (only torque at 90°/s decreased at 24h). Exercise increased DOMS throughout recovery but KJRM and pain remained unchanged. CK, LDH, and uric acid increased similarly in both groups. CRP remained unaffected by exercise while IL-6 increased only post-exercise. TBARS, PC, LPH, GSSG, and TAC increased only post-exercise in both groups. GSH and GSH/GSSG declined post-exercise and normalized thereafter. Catalase and GPX increased only in patients post-exercise.
  
  
  CONCLUSIONS
  Isokinetic exercise induces only a mild inflammatory response of very short duration (<24h) without affecting physical function and pain in KOA patients suggesting that moderate strengthening-type exercise may be safe for this patient cohort. These results indicate that KOA patients may be able to receive another exercise stimulus after only 48h.
  
  
  CONCLUSIONS
  Isokinetic exercise produces minimal inflammation and pain in knee osteoarthritis patients, could be performed every 48h during rehabilitation, and up-regulates patients' antioxidant system.
authors.affiliation: Democritus University of Thrace, Department of Physical Education & Sport Science, Komotini, Greece.
authors.forename: Evangelia I
authors.initials: EI
authors.lastname: Germanou
authors.forename: Athanasios
authors.initials: A
authors.lastname: Chatzinikolaou
authors.forename: Paraskevi
authors.initials: P
authors.lastname: Malliou
authors.forename: Anastasia
authors.initials: A
authors.lastname: Beneka
authors.forename: Athanasios Z
authors.initials: AZ
authors.lastname: Jamurtas
authors.forename: Christos
authors.initials: C
authors.lastname: Bikos
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Tsoukas
authors.forename: Apostolos
authors.initials: A
authors.lastname: Theodorou
authors.forename: Ioannis
authors.initials: I
authors.lastname: Katrabasas
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Margonis
authors.forename: Ioannis
authors.initials: I
authors.lastname: Douroudos
authors.forename: Asimenia
authors.initials: A
authors.lastname: Gioftsidou
authors.forename: Ioannis G
authors.initials: IG
authors.lastname: Fatouros
mesh_terms: D000368:Aged; D000886:Anthropometry; D015992:Body Mass Index; D003430:Cross-Sectional Studies; D005081:Exercise Therapy / Q000379:methods*; D005260:Female; D006801:Humans; D018836:Inflammation Mediators / Q000032:analysis / Q000097:blood*; D015850:Interleukin-6 / Q000097:blood; D007537:Isometric Contraction; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000378:metabolism; D009765:Obesity / Q000150:complications / Q000175:diagnosis*; D020370:Osteoarthritis, Knee / Q000150:complications / Q000175:diagnosis / Q000534:rehabilitation*; D018384:Oxidative Stress / Q000502:physiology*; D012016:Reference Values; D012720:Severity of Illness Index; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism
chemical_list: D018836:Inflammation Mediators; D015850:Interleukin-6; D017392:Thiobarbituric Acid Reactive Substances