1) Heavily and strongly built 2) Sturdy 3) With nervous energy 
strong; robust; morbidly active
• (a.) Strong; active; -- said especially of morbid states attended with excessive action of the heart and blood vessels, and characterized by strength and activity of the muscular and nervous system; as, a sthenic fever.
(sthen´ik) active; strong.
Sthen'ic adjective [ Greek ... strength: confer French sthénique .] (Medicine) Strong; active; -- said especially of morbid states attended with excessive action of the heart and blood vessels, and characterized by strength and activity of the muscular and nervous system; as, a sthenic
Type: Term Pronunciation: sthen′ik Definitions: 1. Active; marked by sthenia; said of a fever with strong bounding pulse, high temperature, and active delirium.
Strong of body or function, even to an excess.
sturdy; heavily and strongly built.