Overstress

[...] the complete frame will withstand a standing and buffing load of 200 tons without overstressing.

“I think we better not catch him anymore right now,” said the vet. “We don’t want to overstress him.”

Susannah, I’m afraid my husband’s been ill for some time—a heart condition. I don’t want to overstress him.

‘And sir, what about my new schemes of things?’ ‘Try them. No harm if you do it along with regular medication, but don’t overstress her.’