they stop briefly between short breaths of anywhere from 2 to 12 strides 句子分析?

they stop briefly between short breaths of anywhere from 2 to 12 strides 句子分析?
还有这句话说得是他们在什么时候停?stop between breaths是在呼吸之间停,还是呼吸的时候停?（我理解的是在呼吸之间停,可是按照常理来说应该是呼吸的时候停）求帮助~
前后文是这样的：reptiles can not run and breathe the same time,they stop briefly between short breaths of anywhere from two to twelve strides,because when they move from side to side,the muscles of the left and right sides contract at different time,to breathe though,these muscles have to contract the same time,mammals do not have these problem,because they do not move from side to side,their feetare in the different position.还有they stop 是停止呼吸还是停止爬行？怎么看出来的？