Strain or tension of mental or bodily powers; strained exertion. (Figurative use of 1g.) Chiefly in… Exhausting effort or strain of mind. Now rare.

Excessive exertion; exertion beyond one's strength or capacity. Also: an instance of this.

Excessive work; work beyond one's capacity or strength.

A spell of exercise taken to stimulate the breathing. Also: something that causes a person to be out of breath or exhausted. Cf. breathing, n. 5. Now…

A fatiguing or exhausting journey or effort; exhausting struggle or toil.

/ˈwɪndə(r)/ Something that takes one's breath away; a blow that ‘knocks the wind’ out of one; a run, climb, or other exertion that puts one out of…

figurative. ? An exhausting piece of exercise, something which ‘takes the wind out’ of one.