By current standards Stuart was physically a small, wiry man, but in fact he was of average build of western European men at that time.
Many years of hard conditions combined with malnutrition, scurvy, trauchoma and other illnesses had rendered him practically blind, in pain and in such poor health that he spent some (900 km) of the return journey of his last expedition (1861-1862) being carried on a litter between two horses.