Exercise Metabolism Research Group, Department of Kinesiology, McMaster University, Hamilton, Ontario.
Muscle Nerve. 2012 Jul;46(1):42-50. doi: 10.1002/mus.23276. Epub 2012 May 29.
Structural evidence of exercise-induced muscle disruption has traditionally involved histological analysis of muscle tissue obtained by needle biopsy, however, there are multiple limitations with this technique. Recently, diffusion tensor magnetic resonance imaging (DT-MRI) has been successfully demonstrated to noninvasively assess skeletal muscle abnormalities induced by traumatic injury.
To determine the potential for DT-MRI to detect musculoskeletal changes after a bout of eccentric exercise, 10 healthy men performed 300 eccentric actions on an isokinetic dynamometer. DT-MRI measurements and muscle biopsies from the vastus lateralis were obtained before and 24 h post-exercise.
Z-band streaming was higher 24 h post-exercise compared with baseline (P < 0.05). The histological indices of damage coincided with changes in DT-MRI parameters of fractional anisotropy (FA) and apparent diffusion coefficient; reflecting altered skeletal muscle geometry (P < 0.05). Z-band streaming quantified per fiber correlated with FA (r = -0.512; P < 0.05).
DT-MRI can detect changes in human skeletal muscle structure following eccentric exercise.
传统上，运动引起的肌肉损伤的结构证据涉及通过针吸活检获得的肌肉组织的组织学分析，然而，该技术有多个局限性。最近，扩散张量磁共振成像（DT-MRI）已成功证明可无创评估外伤性损伤引起的骨骼肌肉异常。
为了确定 DT-MRI 在单次离心运动后检测运动系统变化的潜力，10 名健康男性在等速测力计上进行了 300 次离心运动。在运动前和运动后 24 小时，从股外侧肌获得 DT-MRI 测量值和肌肉活检。
与基线相比，运动后 24 小时的 Z 带流更高（P < 0.05）。损伤的组织学指数与 DT-MRI 参数各向异性分数（FA）和表观扩散系数的变化一致；反映骨骼肌肉几何形状的改变（P < 0.05）。每根纤维的 Z 带流定量与 FA 相关（r = -0.512；P < 0.05）。
DT-MRI 可以检测离心运动后人体骨骼肌结构的变化。
