to make too much physical or mental effort

She told me to get plenty of sleep and not overexert myself during the day.

If you overexert yourself, the wound may begin to bleed. 如果你用力过度，伤口可能会开始流血。

Never overexert yourself before you've properly warmed up.

If you put players under too much pressure, they have a tendency to overexert themselves and that's not good either.

Don't overexert yourself in this heat.

to make too much mental or physical effort, or to cause a person or an animal to do this

Horse owners should be careful not to overexert their ponies. 马主应该小心，不要让他们的小马过度劳累。

Overexerting mentally or physically can exacerbate symptoms.