title: On the correlation between T(2) and tissue diffusion coefficients in exercised muscle: quantitative measurements at 3T within the tibialis anterior.
abstract: OBJECTIVE
  To assess the transverse relaxation time T(2) and diffusion coefficient D before and following exercise in the tibialis anterior muscle and determine whether T(2) and D values were correlated.
  
  
  METHODS
  Measurements of T(2) and D were performed at 3 T within axial slices through the calf muscles of six healthy volunteers at 95 s intervals before and for 10-12 min after a dorsiflexion exercise to exhaustion.
  
  
  RESULTS
  The mean +/- standard deviation (SD) of T(2) and D before exercise were 32 +/- 1.55 ms and 1.52 +/- 0.15 mum(2)/ms, and after exercise were 43 +/- 2.5 ms and 1.72 +/- 0.13 mum(2)/ms, respectively. The mean +/- SD inter-individual recovery times of the % change in T(2) and D after exercise were 7.9 +/- 4.2 and 10.9 +/- 7.0 min, respectively. The T(2) and D values showed a significant correlation throughout the experiments (r (2) = 0.45).
  
  
  CONCLUSIONS
  The increase in T(2) of skeletal muscle after exercise is correlated with the increase of the diffusion coefficient D and the recovery times appear similar, indicating that any model used to explain T(2) increases with exercise must also account for increased diffusion coefficients.
authors.affiliation: Department of Physics, Yarmouk University, Irbid, Jordan. zababneh@yu.edu.jo
authors.forename: Zaid Q
authors.initials: ZQ
authors.lastname: Ababneh
authors.forename: Riad
authors.initials: R
authors.lastname: Ababneh
authors.forename: Stephan E
authors.initials: SE
authors.lastname: Maier
authors.forename: Carl S
authors.initials: CS
authors.lastname: Winalski
authors.forename: Koichi
authors.initials: K
authors.lastname: Oshio
authors.forename: Anas M
authors.initials: AM
authors.lastname: Ababneh
authors.forename: Robert V
authors.initials: RV
authors.lastname: Mulkern
mesh_terms: D000328:Adult; D015444:Exercise / Q000502:physiology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009119:Muscle Contraction / Q000502:physiology*; D018482:Muscle, Skeletal / Q000033:anatomy & histology / Q000502:physiology*