Although mild leg pain and shortness of breath can be a normal side effect of an especially vigorous exercise session, severe symptoms can indicate more serious medical conditions that require prompt medical treatment. Seek emergency medical treatment if you experience severe shortness of breath along with chest pain and swollen legs and feet.
Pregnancy and hormonal birth control put women at an increased risk of developing deep vein thrombosis, a condition that occurs when a blood clot forms in the deep veins of your body, such as your legs. Other conditions that can cause deep vein thrombosis – DVT -- include hormone replacement therapy, a lack of regular exercise, smoking, long-distance travel, bed rest and lengthy surgeries. If the clot breaks loose, it can travel to your lungs and cause a life-threatening condition, known as pulmonary embolism, or a heart attack or stroke.
Exercise doesn't cause deep vein thrombosis and pulmonary embolism, although it might exacerbate the symptoms and make them more obvious. Only half of people suffering from deep vein thrombosis experience typical symptoms, according to the Vascular Disease Foundation. The most common symptoms of DVT include pain and swelling of one leg, pain or tenderness in the groin or calf muscle and fullness of the veins just beneath the skin. If it progresses to pulmonary embolism, you might experience sudden, severe shortness of breath along with sharp chest pain. The chest pain and shortness of breath doesn't go away when you stop exercising.
If you have deep vein thrombosis but not a pulmonary embolism, your treatment should focus on stopping the clot from getting bigger and preventing a recurrence. Your doctor may prescribe blood thinning medications, which you will probably need to take for three months or longer. You might also need to wear compression stockings, which gently squeeze your legs, to keep blood flowing more effectively through your veins. To prevent serious complications or death, doctors treat a pulmonary embolism immediately with anti-clotting medications, including anticoagulants and clot dissolvers. Clot dissolvers carry an increased risk of excessive bleeding, so doctors only use them in life-threatening situations. If these medications don't work, or if the clot is especially large, doctors might need to surgically remove the clot.
Regular exercise, especially during pregnancy and middle age, can help decrease your odds of developing DVT. Women should avoid smoking, especially while on hormonal birth control pills or hormone replacement therapy, and stay at a healthy weight. Seet your doctor for an annual well woman exam to ensure your medications and treatments remain safe and appropriate.