Deficient in physical strength; weak; infirm; debilitated.

Wanting force, vigor, or efficiency in action or expression; not full, loud, bright, strong, rapid, etc.; faint; as, a feeble color; feeble motion.

pathetically lacking in force or effectiveness; "a feeble excuse"; "a lame argument"

Back peg grinding with front tire on top of obstacle.

Back peg grinding while the front tire is on top of the obstacle.

To make feble; to enfeeble.

What old fencers eventually become.