title: Explanatory models of muscle performance in acromegaly patients evaluated by knee isokinetic dynamometry: Implications for rehabilitation.
abstract: OBJECTIVE
  To evaluate the effects of demographics and hormonal variations on knee muscle performance in patients with acromegaly and develop explanatory models of peripheral muscle function in these individuals.
  
  
  METHODS
  This was a cross-sectional study in which 53 acromegalics and 27 healthy subjects underwent knee isokinetic dynamometry to evaluate the peak torque value for leg extension at 75°/s (PTE75) and 240°/s (PTE240). Separate multivariable linear regression models for the prediction of PTE75 and PTE240 were tested using variables commonly used as predictors in the clinical setting and other specific variables related to acromegaly.
  
  
  RESULTS
  The final prediction model for PTE75 (R(2)=0.888; adjusted R(2)=0.820, SE of bias=16.2Nm, p<0.001) was -0.221×growth hormone+36.791×sexmale=1-27.407×statusactive=1-0.690×age+148.071. The final prediction model for PTE240 (R(2)=0.816; adjusted R(2)=0.805, SE of bias=8.8Nm, p<0.001) was -0.174×growth hormone+12.522×sexmale=1-0.520×age+98.099.
  
  
  CONCLUSIONS
  In acromegalics, high growth hormone levels, female gender, and older age are associated with reduced muscle strength and endurance. Additionally, active disease negatively affects peripheral muscle strength in these patients.
authors.affiliation: Rehabilitation Sciences Post-Graduation Program, Augusto Motta University Center, Av. Paris 72, Bonsucesso, Rio de Janeiro, Brazil. Electronic address: phel.lop@uol.com.br.
authors.forename: Agnaldo José
authors.initials: AJ
authors.lastname: Lopes
authors.affiliation: Rehabilitation Sciences Post-Graduation Program, Augusto Motta University Center, Av. Paris 72, Bonsucesso, Rio de Janeiro, Brazil. Electronic address: arthurde@unisuamdoc.com.br.
authors.forename: Arthur Sá
authors.initials: AS
authors.lastname: Ferreira
authors.affiliation: Rehabilitation Sciences Post-Graduation Program, Augusto Motta University Center, Av. Paris 72, Bonsucesso, Rio de Janeiro, Brazil. Electronic address: evelynwalchan@yahoo.com.br.
authors.forename: Evelyn Mendes
authors.initials: EM
authors.lastname: Walchan
authors.affiliation: Admiral Adalberto Nunes Physical Education Center (Brazilian Navy), Av. Brasil, 10590, Penha, Rio de Janeiro, Brazil. Electronic address: mauricio-soares@hotmail.com.
authors.forename: Mauricio Santos
authors.initials: MS
authors.lastname: Soares
authors.affiliation: Admiral Adalberto Nunes Physical Education Center (Brazilian Navy), Av. Brasil, 10590, Penha, Rio de Janeiro, Brazil. Electronic address: priscilabunn@yahoo.com.br.
authors.forename: Priscila Santos
authors.initials: PS
authors.lastname: Bunn
authors.affiliation: Rehabilitation Sciences Post-Graduation Program, Augusto Motta University Center, Av. Paris 72, Bonsucesso, Rio de Janeiro, Brazil; Physical Therapy Department, Federal University of Rio de Janeiro, R. Prof. Rodolpho Paulo Rocco, 255, Cidade Universitária, Rio de Janeiro, Brazil. Electronic address: fguimaraes_pg@yahoo.com.br.
authors.forename: Fernando Silva
authors.initials: FS
authors.lastname: Guimarães
mesh_terms: D000172:Acromegaly / Q000175:diagnosis* / Q000503:physiopathology* / Q000534:rehabilitation; D000328:Adult; D000367:Age Factors; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007537:Isometric Contraction / Q000502:physiology*; D007719:Knee Joint / Q000503:physiopathology*; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D053580:Muscle Strength / Q000502:physiology; D053581:Muscle Strength Dynamometer; D018482:Muscle, Skeletal / Q000503:physiopathology*; D010807:Physical Endurance / Q000502:physiology; D052097:Quadriceps Muscle / Q000503:physiopathology; D012737:Sex Factors; D019415:Torque
keywords: Acromegaly; Muscle strength; Rehabilitation