title: Assessment of functional impairment after knee anterior cruciate ligament reconstruction using cardiorespiratory parameters: a cross-sectional study.
abstract: BACKGROUND
  A dynamic sub-maximum exercise with the same absolute intensity, performed with different muscle groups, may present exacerbated cardiorespiratory responses. Therefore, cardiorespiratory responses to unilateral exercise may identify bilateral differences. The purpose of this study was to verify whether the cardiorespiratory responses to lower limb exercise display counter-lateral differences, and if they could be used to assist athletes and health professionals involved in rehabilitation.
  
  
  METHODS
  Nine individuals participated in this cross-sectional study. They had been treated in a private rehabilitation clinic and submitted to intra-articular reconstruction of the anterior cruciate ligament. The cycling exercise with the same sub-maximal intensity and with one lower limb was used to gather data. Cardiorespiratory responses to exercise were compared between exercises performed with the involved and uninvolved limb after five minutes of exercise.
  
  
  RESULTS
  Cardiorespiratory responses to exercise performed with the involved limb presented higher values after five minutes of cycling: oxygen uptake (+7%), carbon dioxide production (+10%), minute ventilation (+20%), breathing frequency (+19%), ventilatory equivalent for oxygen (+14%), end-tidal pressure of O2 oxygen (+4%), end-tidal pressure of O2 carbon dioxide (-9%) and heart rate (+9%).
  
  
  CONCLUSIONS
  The exacerbated responses, including increase of the ventilatory equivalent and decrease of end-tidal pressure of carbon dioxide, indicate that this exercise protocol may be useful in the characterization of the functional deficit of the surgical limb during rehabilitation.
authors.affiliation: Departamento de Fisiologia, Universidade Federal de São Paulo, São Paulo, Brazil. marilia1707@gmail.com.
authors.forename: Marília Santos
authors.initials: MS
authors.lastname: Andrade
authors.forename: Claudio Andre Barbosa
authors.initials: CA
authors.lastname: de Lira
authors.forename: Rodrigo Luiz
authors.initials: RL
authors.lastname: Vancini
authors.forename: Fernanda Patti
authors.initials: FP
authors.lastname: Nakamoto
authors.forename: Moisés
authors.initials: M
authors.lastname: Cohen
authors.forename: Antonio Carlos
authors.initials: AC
authors.lastname: da Silva
mesh_terms: D000328:Adult; D059549:Anterior Cruciate Ligament Reconstruction / Q000379:methods*; D005080:Exercise Test / Q000379:methods*; D005260:Female; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D007718:Knee Injuries / Q000503:physiopathology / Q000601:surgery*; D008297:Male; D012123:Pulmonary Ventilation / Q000502:physiology*; D020127:Recovery of Function / Q000502:physiology*; D012129:Respiratory Function Tests / Q000379:methods; D015656:Respiratory Mechanics / Q000502:physiology