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.
Leg cramps may happen for several reasons: lack of fluids, injury, muscle strain, or staying in the same position for a long period of time. Blood circulation problems or pressure on the nerves in the spine can also cause cramp-like pains in your legs. Other common causes include: 1  Pregnancy. 2  Diabetes. 3  Decreased potassium level. 4  Neuromuscular disorders, such as Parkinsonâs disease. 5  Certain medications. 6  Alcohol and excess caffeine use. 7  Several vitamin deficiencies may directly or indirectly lead to muscle cramps including thiamine, pantothenic acid, and vitamin B6.