Muscles come and go flab lasts.

A dry, self-deprecating joke about aging and the body’s tendency to lose hard-won fitness while retaining (or accumulating) fat. The line plays on the contrast between “muscles,” associated with effort, discipline, and temporary peak condition, and “flab,” associated with ease, inertia, and persistence. Vaughan’s humor turns a common frustration—how quickly conditioning fades compared with how stubborn weight can be—into a memorable aphorism. Implicitly, it also pokes fun at the optimism of fitness fads and the illusion of permanence in physical self-improvement, reminding readers that bodily change is often asymmetrical and time is undefeated.