untoned
Soft and slack
Untoned describes something lacking tone or firmness, most often applied to muscles that haven't been shaped through exercise: untoned arms, an untoned midsection.
The word also appears in photography and printing for images that haven't undergone toning—a process that alters color or contrast.
Absence of tautness
jiggly · squishy · doughy · floppy · undefined · shapeless · unfit · sedentary
slack
Absence of tautness
flaccid · jiggly · squishy · doughy · floppy · undefined · shapeless · unfit · sedentary · neglected
washed-out
Lacking original vibrancy
flat · colorless · lifeless · drab · wan · pallid · lackluster · desaturated · bleached · neutral
feeble
Weak and ineffective
enervated · sapped · exhausted · depleted · fragile · delicate · powerless · ineffectual · debilitated · frail
tone, tonic, toned, monotone, intonation, intone, toning, undertone, detonation