title: The immediate effect of long-distance running on T2 and T2* relaxation times of articular cartilage of the knee in young healthy adults at 3.0 T MR imaging.
abstract: OBJECTIVE
  To quantitatively assess the immediate effect of long-distance running on T2 and T2* relaxation times of the articular cartilage of the knee at 3.0 T in young healthy adults.
  
  
  METHODS
  30 healthy male adults (18-31 years) who perform sports at an amateur level underwent an initial MRI at 3.0 T with T2 weighted [16 echo times (TEs): 9.7-154.6 ms] and T2* weighted (24 TEs: 4.6-53.6 ms) relaxation measurements. Thereafter, all participants performed a 45-min run. After the run, all individuals were immediately re-examined. Data sets were post-processed using dedicated software (ImageJ; National Institute of Health, Bethesda, MD). 22 regions of interest were manually drawn in segmented areas of the femoral, tibial and patellar cartilage. For statistical evaluation, Pearson product-moment correlation coefficients and confidence intervals were computed.
  
  
  RESULTS
  Mean initial values were 35.7 ms for T2 and 25.1 ms for T2*. After the run, a significant decrease in the mean T2 and T2* relaxation times was observed for all segments in all participants. A mean decrease of relaxation time was observed for T2 with 4.6 ms (±3.6 ms) and for T2* with 3.6 ms (±5.1 ms) after running.
  
  
  CONCLUSIONS
  A significant decrease could be observed in all cartilage segments for both biomarkers. Both quantitative techniques, T2 and T2*, seem to be valuable parameters in the evaluation of immediate changes in the cartilage ultrastructure after running.
  
  
  CONCLUSIONS
  This is the first direct comparison of immediate changes in T2 and T2* relaxation times after running in healthy adults.
authors.affiliation: 1 Department of Diagnostic and Interventional Radiology, University Medical Center, Hamburg-Eppendorf, Hamburg, Germany.
authors.forename: Cyrus
authors.initials: C
authors.lastname: Behzadi
authors.affiliation: 2 Department of Sports Medicine, University Medical Center, Hamburg-Eppendorf, Hamburg, Germany.
authors.forename: Goetz H
authors.initials: GH
authors.lastname: Welsch
authors.affiliation: 1 Department of Diagnostic and Interventional Radiology, University Medical Center, Hamburg-Eppendorf, Hamburg, Germany.
authors.forename: Azien
authors.initials: A
authors.lastname: Laqmani
authors.affiliation: 1 Department of Diagnostic and Interventional Radiology, University Medical Center, Hamburg-Eppendorf, Hamburg, Germany.
authors.forename: Frank O
authors.initials: FO
authors.lastname: Henes
authors.affiliation: 1 Department of Diagnostic and Interventional Radiology, University Medical Center, Hamburg-Eppendorf, Hamburg, Germany.
authors.forename: Michael G
authors.initials: MG
authors.lastname: Kaul
authors.affiliation: 3 Department of Medical Biometry and Epidemiology, University Medical Center, Hamburg-Eppendorf, Hamburg, Germany.
authors.forename: Gerhard
authors.initials: G
authors.lastname: Schoen
authors.affiliation: 1 Department of Diagnostic and Interventional Radiology, University Medical Center, Hamburg-Eppendorf, Hamburg, Germany.
authors.forename: Gerhard
authors.initials: G
authors.lastname: Adam
authors.affiliation: 1 Department of Diagnostic and Interventional Radiology, University Medical Center, Hamburg-Eppendorf, Hamburg, Germany.
authors.forename: Marc
authors.initials: M
authors.lastname: Regier
mesh_terms: D000293:Adolescent; D000328:Adult; D002358:Cartilage, Articular / Q000000981:diagnostic imaging* / Q000502:physiology*; D005240:Feasibility Studies; D006801:Humans; D007719:Knee Joint / Q000000981:diagnostic imaging* / Q000502:physiology*; D008279:Magnetic Resonance Imaging; D008297:Male; D012016:Reference Values; D012420:Running / Q000502:physiology*; D013997:Time Factors; D055815:Young Adult