If the brain's blood supply is decreased too much, the person may pass out (syncope). Symptoms may worsen when changing position from lying down or sitting, to standing up. In addition to feeling dizzy, associated symptoms may include: 1  Sweating. 2  Weakness. 3  Nausea and vomiting. 4  Shortness of breath. 5  Chest pain.
Although most muscle cramps are harmless, some may be related to an underlying medical condition, such as: 1  Inadequate blood supply. Narrowing of the arteries that deliver blood to your legs (arteriosclerosis of the extremities) can produce cramp-like pain in your legs and feet while you're exercising. 2  Nerve compression.
Painful experience. A few days after the race I did some research on leg cramps. My notes from then are the basis of this article. So why did I get those calf cramps? There is no clear cause for leg cramps. Surprising answer? But yes, the running experts are still uncertain. Eventhough a number of factors possibly causing calf cramps have been identified.