Kept fit by exercise; able to withstand physical exertion without becoming out of breath; strong, untiring; (also) fully or well rested. Also in…

Capable of continuing in action for a long time without becoming out of breath; (hence) healthy, fit, robust. Also: prolix, tediously lengthy. Cf. l…

= fit, adj.

Capable of doing something for a long time without becoming breathless; long-breathed, robust, enduring. Also: characteristic of prolonged effort or…

In colloquial phrases: as fine as a fiddle = as fit as a fiddle. as fit as a fiddle: in good ‘form’ or condition. to hang up one's fiddle: to…

Of body or mind: Brought into tone (tone, n. 7); braced, strung. Chiefly with adverb, as toned-up. well-toned: see well-toned, adj.

Firmly supported or reinforced; (also) thoroughly prepared mentally.

In Horse Racing or Athletics: In good ‘form’ or condition; hence colloquial in good health, perfectly well. fit as a fiddle: see fiddle, n. phrases.

Colloquial phrase (as) fit as a flea, fine, very fit. Cf. as fit as a fiddle at fiddle, n. phrases.

fit to fight; fit enough to take part in a fight.

colloquial. Fit, well, thriving. Cf. pink, n.5 3b. rare.

Physically toned by aerobic exercise.