时差N小时 肌肉生而不平等?(下)（在线收听）

So they can contract more slowly, but can keep going without burning themselves out.

所以，慢收缩肌肉纤维收缩更慢，但是持续时间更长。

Right, slow-twitch fibers have a lot of myoglobin, a protein that helps transfer oxygen into the mitochondria, the power houses of the cell that produce cellular energy.

慢收缩肌肉纤维含有大量的肌红蛋白，这是一种帮助氧气进入线粒体的蛋白质，线粒体是细胞产生细胞能量的能量屋。

So marathon runners must have a lot of slow twitch muscle fibers.

那么，马拉松选手肯定有很多慢收缩肌肉纤维了。

Exactly, since they have to keep going for long periods.

说的对，因为马拉松耗能耗时长。

So, sprinters must have a lot of fast-twitch muscle fibers.

所以，短跑运动员必须有很多快速收缩的肌肉纤维。

Right! Fast twitch fibers consume energy quickly and are good for short, powerful bursts of movement like sprinting and jumping.

对，快收缩肌肉纤维耗能快，特别适合短而有力的爆发性动作，比如短跑和跳跃，

World-class sprinters typically have about 80% fast twitchmuscle fiber.

世界级短跑健将体内80%肌肉都是快收缩肌肉纤维。

Luck dogs!

真是幸福!

And, of course, they train incredibly hard to develop their natural gifts. Olympic gold is not won by muscle fiber alone.

当然，他们不仅仅靠天赋，还有艰苦地训练来完善技能。获得奥运金牌可并非肌肉纤维就可以。

But it certainly helps!

但是不得不承认肌肉纤维起了作用。