Isometric and dynamic exercise studied with echo planar magnetic resonance imaging (MRI)
Isometric and dynamic exercise studied with echo planar magnetic resonance imaging (MRI)
复制标题
DOI：
10.1097/00005768-199809000-00006
复制
发表时间：
1998-09-01
期刊：
影响因子：
--
通讯作者：
Gore, JC
中科院分区：
文献类型：
--
作者：
Price, TB;Kennan, RP;Gore, JC
目的：在匹配负荷和持续时间的动态和等长背屈运动期间和之后，研究不同类型的运动对回波平面（EP）磁共振（MR）图像的影响。方法：健康的未受过训练的受试者进行全范围运动和恒定阻力的动态运动，或在运动范围中心进行等距运动，恒定阻力为其测量的最大自愿收缩（MVC）的25%或70%。在运动前（4张）、运动中（27张）和运动后（29-65张）以1.5 T每4 s采集一次EP MR图像。自旋回波EP序列，TE = 30 ms。TR = 4000 ms, FOV = 20 × 40 cm， 64 × 128矩阵。根据运动期间和运动后不同时间的单个图像，计算质子横向弛豫率δ R-2， [s(-1)])相对于运动前的变化。结果：在70和25%的MVC中，动态运动后的最大Delta R-2 (-8.38 +/- 0.32 s(-1) (70%), -6.47 +/- 1.23 s（-1)(25%)）显著大于等长运动后(-5.91 +/- 0.67 s(-1) (70%) （P < 0.05）。-3.80 +/- 0.87 s（-1) (25%)）在监测恢复情况的整个期间，Delta R-2在两种工作负荷下进行等长运动和动态运动后的恢复模式保持平行。结论：我们得出结论，运动引起的MR图像变化不仅受工作量和运动时间的影响，还受运动类型的影响，我们假设这些差异是由不同类型的运动引起的不同生理反应引起的。
Purpose: The effect of different types of exercise upon echo planar (EP) magnetic resonance (MR) images was examined during and after both dynamic and isometric dorsi-flexion exercises at matched workloads and durations. Methods: Healthy untrained subjects performed either dynamic exercise through a full range of motion and against a constant resistance or isometric exercise at the center of the range of motion and against a constant resistance at 25 or 70% their measured maximum voluntary contraction (MVC). EP MR images were acquired at 1.5 T every 4 s before (4 images), during (27 images), and after (29-65 images) exercise. A spin echo EP sequence was employed with TE = 30 ms. TR = 4000 ms, FOV = 20 x 40 cm. 64 x 128 matrix. The changes in proton transverse relaxation rate Delta R-2, [s(-1)]) relative to values obtained before exercise were calculated from individual images at different times during and after exercise. Results: At both 70 and 25% of MVC, the maximum Delta R-2 after dynamic exercise (-8.38 +/- 0.32 s(-1) (70%), -6.47 +/- 1.23 s(-1) (25%)) was significantly greater (P less than or equal to 0.05) than after isometric exercise(-5.91 +/- 0.67 s(-1) (70%). -3.80 +/- 0.87 s(-1) (25%)). Throughout the period that recovery was monitored, the recovery patterns of Delta R-2 following isometric and dynamic exercise at both workloads remained parallel. Conclusions: We conclude that exercise-induced changes in MR images are influenced not only by workload and exercise duration but also by the type of exercise, and we postulate that these differences result from the different physiological responses elicited by the different types of exercise.