Losing more sweat in peacetime (training, etc.) means shedding less blood in war.

平时多流汗，战时少流血。

《新英汉大辞典》

But that can mean less blood reaches muscles.

但这就意味着流入肌肉的血液会减少。

youdao

Data showed that when people were offered a stipend for their donation, less blood was given.

数据显示，如果向献血的人提供一定的奖金回报时，献血量就会减少。

youdao

Doctor Alderman says that eating less salt results in lower blood pressure.

VOA: special.2010.03.03

If he splits his head open and there's blood everywhere, I'm less likely to laugh unless I don't like him or something.

如果他摔个头破血流，我就笑不出，除非我很讨厌这个人。

耶鲁公开课 - 心理学导论课程节选

The peak occurs a little bit later and then there's a less rapid decline here, and then blood sugar actually ends up a little above this initial level, and therefore you're less likely to eat because you're less hungry.

峰值出现得比较晚,下降也较为缓慢,最后血糖结束在比起始值稍高的位置,因此人就没有那么想进食 因为不感觉饿

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选