Abstract: Electronic device which may be worn by a user while moving about. Senses muscle actions of lower leg by switch under foot and is capable of monitoring ankle motion. Signals to user when ankle flexing motion is not of sufficient amplitude or leg muscle action is not performed frequent enough to enhance the circulation of blood, which helps to prevent vascular stasis and dependent edema associated with prolong periods of sitting or standing without muscle activity. Signals to user when ankle flexing motion is not of sufficient amplitude or leg muscle action is not performed frequently enough to enhance the circulation of blood, which helps to prevent vascular stasis and dependent edema associated with prolonged periods of sitting or standing without muscle activity. One embodiment may be worn while standing or sitting in a vehicle.