长跑运动时有大量血液流到下吱。同时由于下肢肌肉交替收缩和舒张,可促使下肢静脉血液回流到心脏,可见,骨对静睬回流起到一种“泵”的作用,称为“肌肉泵”如果长跑到了终点就立刻停下来休息,肌肉停止收缩,“肌肉泵”的作用就会突然消失,之量的血液因重力关系停留在下肢,回心血液量就会突然急剧减少,心脏输出血量也会大大 A lot of blood flow to the next sigh when long-distance running. At the same time as the lower extremity muscle alternating contraction and relaxation, can promote lower extremity venous blood back to the heart, we can see that the bones on the quiet return play a “pump” effect, called “muscle pump” if the long-distance run to the end stop immediately to rest , The muscle stops contracting, the role of “muscle pump” will suddenly disappear, the amount of blood stays in the lower extremities due to the relationship of gravity, the blood back to the sudden sharp decline in blood output will be greatly cardiac output