<unk>  (aka residual<unk>  tension or tonus) is the continuous and passive partial contraction of the<unk> s. It helps maintain posture, and it declines during REM sleep. Note that muscular<unk>  is not defined as muscular shaping or the aspect of general Human physical appearance.
Muscle tone
Blood flow
Cardiac cycle
Hemodynamics
Respiratory rate
Heart rate
Thermoregulation
Cough reflex