Takahashi H, Kuno S, Miyamoto T, Yoshioka H, Inaki M, Akima H, Katsuta S, Anno I, Itai Y
Department of Radiology, University of Tsukuba, Ibaraki, Japan.
Eur J Appl Physiol Occup Physiol. 1994;69(5):408-13. doi: 10.1007/BF00865404.
To investigate the time-course of changes in transverse relaxation time (T2) and cross-sectional area (CSA) of the quadriceps muscle after a single session of eccentric exercise, magnetic resonance imaging was performed on six healthy male volunteers before and at 0, 7, 15, 20, 30 and 60 min and 12, 24, 36, 48, 72 and 168 h after exercise. Although there was almost no muscle soreness immediately after exercise, it started to increase 1 day after, peaking 1-2 days after the exercise (P < 0.01). Immediately after exercise, T2 increased significantly in the rectus femoris, vastus lateralis and intermedius muscles (P < 0.05) and decreased quickly continuing until 60 min after exercise. At and after the 12th h, a significant increase was perceived again in the T2 values of the vastus lateralis and intermedius muscles (P < 0.01) [maximum 9.3 (SEM 2.8)% and 10.9 (SEM 2.2)%, respectively]. The maximal values were exhibited at 24-36 h after exercise. In contrast, the rectus femoris muscle showed no delayed-stage increase. Also, in CSA, an increase after 12 h was observed in addition to the one immediately after exercise in the vastus lateralis, intermedius and medialis and quadriceps muscles as a whole (P < 0.01), reaching the maximal values at 12-24 h after exercise. The plasma creatine kinase activity remained unchanged up to 24 h after and then increased significantly 48 h after exercise (P < 0.05). Beginning 12 h after exercise, the subjects whose T2 and CSA increased less than the others displayed a faster decrease in muscle soreness.(ABSTRACT TRUNCATED AT 250 WORDS)
为研究单次离心运动后股四头肌横向弛豫时间（T2）和横截面积（CSA）的时程变化，对6名健康男性志愿者在运动前、运动后0、7、15、20、30和60分钟以及12、24、36、48、72和168小时进行了磁共振成像检查。运动后即刻几乎没有肌肉酸痛，但在运动1天后开始增加，在运动后1 - 2天达到峰值（P < 0.01）。运动后即刻，股直肌、股外侧肌和股中间肌的T2显著增加（P < 0.05），并迅速下降，持续到运动后60分钟。在第12小时及之后，股外侧肌和股中间肌的T2值再次显著增加（P < 0.01）[分别最大增加9.3（标准误2.8）%和10.9（标准误2.2）%]。最大值出现在运动后24 - 36小时。相比之下，股直肌未显示出延迟期增加。此外，在CSA方面，股外侧肌、股中间肌、股内侧肌以及整个股四头肌在运动后即刻增加外，在12小时后也出现增加（P < 0.01），在运动后12 - 24小时达到最大值。血浆肌酸激酶活性在运动后24小时内保持不变，然后在运动后48小时显著增加（P < 0.05）。运动后12小时开始，T2和CSA增加少于其他人的受试者肌肉酸痛减轻得更快。（摘要截短于250字）
