Now, remember those tiny myofibrils that bundle up to form your muscle fibers?

现在，那些微小肌原捆绑形成你肌肉吗？

Thousands of tiny, parallel threads called myofibrils squish together to form muscle fibers, which are your actual muscle cells — cells with mitochondria, multiple nuclei, and a cellular membrane called a sarcolemma.

数以千计被称为肌原微小平行线挤压在一起形成肌肉，这就是你真正肌肉细胞——具有线粒体、多个细胞核和称为肌膜细胞膜细胞。