Humans rely on the leg muscles for innumerable activities. Whether standing motionless or engaging in a competitive sprint, the leg muscles support the body. A variety of temporary or chronic conditions and diseases can interfere with the normal activity of the leg muscles, leading to pain and cramps. Persistent leg muscle pain and cramps warrant a medical evaluation to determine the underlying cause.
Dehydration and Electrolyte Abnormalities
Working or playing in a warm environment may cause dehydration due to excess fluid loss from perspiring. Sweat contains high concentrations of body salts, or electrolytes, including sodium and potassium. The combination of dehydration and loss of electrolytes may lead to painful leg muscle cramps, according to the American Academy of Orthopaedic Surgeons. Holding the muscle in a stretched position and gently rubbing the area may help the cramped muscle relax. Drinking fluids while exercising in a warm environment helps prevent dehydration.
Muscle Fatigue
Painful muscle cramps may develop in the legs during or after overexertion, according to the University of Iowa Hospitals and Clinics. Physical exertion beyond a person's level of conditioning can lead to an accumulation of metabolic byproducts in the muscle tissue, which triggers muscle contractions. A nerve-mediated reflex sends signals to the muscle to hold the contraction, resulting in a painful cramp. Warming up and stretching before exercise may help reduce the likelihood of leg pain and cramps.
Peripheral Arterial Disease
Buildup of fat and calcium in the arteries that supply blood to the legs causes peripheral arterial disease, a condition that affects approximately 8 million to 12 million adults in the United States, according to the National Heart, Lung and Blood Institute. The areas of fatty buildup, known as plaques, partially obstruct blood flow to the legs. The obstructed blood vessels cannot deliver sufficient blood to the leg muscles to meet the cells' oxygen demands during exercise. Painful leg cramps or aching pain commonly results, affecting the muscles of the calves, thighs and buttocks. Patients with peripheral arterial disease can often improve their condition by stopping smoking, following a low-fat diet and participating in a prescribed exercise program.
Amyotrophic Lateral Sclerosis
Painful leg cramps, weakness and twitching may be early symptoms of amyotrophic lateral sclerosis, also known as Lou Gehrig's disease or ALS. The disorder causes a progressive degeneration and loss of the nerve cells that direct muscle movement. As these cells deteriorate and die, patients gradually lose control of their muscles and eventually experience paralysis, says the National Institute of Neurological Disorders and Stroke. Although biomedical researchers continue to study ALS, effective treatment and cure remain elusive.
Metabolic Myopathy
Metabolic myopathies are uncommon inherited disorders that disrupt normal muscle metabolism. Patients with these disorders may experience severe pain and muscle cramps involving the legs or other muscle groups with physical exertion, according to the American College of Rheumatology. Patients with these conditions may benefit from a prescribed aerobic exercise program.
References
- American Academy of Orthopaedic Surgeons: Muscle Cramp
- University of Iowa Hospitals and Clinics: Charley Horse-Muscle Cramps
- National Heart, Lung and Blood Institute: Peripheral Arterial Disease
- National Institute of Neurological Disorders and Stroke: Amyotrophic Lateral Sclerosis
- American College of Rheumatology: Metabolic Myopathies
