man-strength

Used to describe the suprising ability of older men (e.g. your father in his 40-50s) to out-lift, out-drink, and generally out-work younger and more physically fit men.

Strength a man is bestowed with in his mid 30's that isn't physically apparent to an outside observer. A man needs to do nothing to recieve it other than grow old. Many unsuspecting sons and young males looking to prove them selves "manly" aren't aware of this phenomenon and underestimate the middle aged man.

Physical strength which is accompanied by intellect and experience which allows a man to totally demolish an opponent of equal strength yet many years younger.

The common strength of a man that seems superhuman to all those who do not possess it. In middle school recess, if you got dared into a friendly wrestling match with that guy (every school has one)who was held-back 2 years and already had a full beard and drove himself to school, you would experience the force of man strength. The fingers seem made of steel and grapple with other-worldly force. Eventually, you will be in a full nelson so tight, you wont be able to get the air out of your constricted neck to muster a vocal signal of capitulation.

the crazy insane strength you gain when you become an old man

when one has hidden strength that only a full grown adult would have.

The uncanny ability of older men to lift copious amounts of lumber, heavy furniture, and beat their sons in arm wrestling.