Koh Timothy J, Peterson Jennifer M, Pizza Francis X, Brooks Susan V
School of Kinesiology, University of Illinois at Chicago, USA.
J Gerontol A Biol Sci Med Sci. 2003 Jul;58(7):592-7. doi: 10.1093/gerona/58.7.b592.
We tested the hypothesis that a single bout of training with passive stretches or isometric contractions protects the extensor digitorum longus muscle in old mice from contraction-induced injury. Lengthening contractions produced similar decreases in force (approximately 70%-80%) and numbers of overtly injured fibers (approximately 15%-20%) in adult and old mice, but twofold greater inflammatory cell accumulation above untreated control values in old versus adult mice. For both age groups, prior training with passive stretches improved postinjury force almost twofold compared with untrained muscles and reduced injured fibers by one half. Training with passive stretches or isometric contractions reduced inflammatory cell accumulation following lengthening contractions by as much as two thirds in old mice, but not in adult mice. The data indicate that passive stretches provide some protection against contraction-induced injury in old mice, and that accumulation of inflammatory cells does not correlate strongly with force deficit and number of injured fibers.
单次进行被动拉伸或等长收缩训练可保护老年小鼠的趾长伸肌免受收缩诱导损伤。在成年和老年小鼠中，延长收缩导致的力量下降幅度相似（约70%-80%），明显受损纤维数量也相似（约15%-20%），但老年小鼠炎症细胞积累量比成年小鼠未处理对照组的值高出两倍。对于两个年龄组，与未训练的肌肉相比，预先进行被动拉伸训练可使损伤后的力量提高近两倍，并使受损纤维数量减少一半。在老年小鼠中，被动拉伸或等长收缩训练可使延长收缩后的炎症细胞积累量减少多达三分之二，但在成年小鼠中则不然。数据表明，被动拉伸可为老年小鼠的收缩诱导损伤提供一定保护，且炎症细胞的积累与力量 deficit 和受损纤维数量并无强烈关联。 （注：原文中“force deficit”似乎有误，可能是“force decrease”之类的表述，这里按原文翻译）
