What Causes Shortness of Breath & Dizziness When Exercising?

These days, we hear more and more about the benefits of exercise. Exercise helps maintain the health of our heart, can aid in weight loss, and may even be beneficial for those who are suffering from depression. In some cases, though, people can develop shortness of breath and dizziness while engaging in their exercise routine. Understanding the causes and dangers of these symptoms is crucial for maintaining safety during your workout.

Shortness of breath during exercise can be a symptom of a more serious condition. (Image: Jupiterimages/Creatas/Getty Images)

Intense Exercise

During exercise, our bodies undergo strain and stress, often resulting in increases in heart rate, blood pressure and respiratory rate. Depending on the difficulty of the exercises, these vital signs may increase only moderately, or to a significant level. Shortness of breath during intense exercise, therefore, is not only a common side effect, but an expected occurrence. In fact, those who do not become short of breath while exercising are often engaging in only mild bouts of activity. During especially intense exercise, peak heart rate levels can also lead to mild to moderate cases of dizziness.

High Blood Pressure

As the difficulty of exercise increases, exercisers can expect to experience an increase in their blood pressure levels. While a moderate bump in blood pressure can be beneficial for the heart, significant rises can be quite dangerous -- and may actually result in the development of shortness of breath and dizziness. Those who have a history of hypertension should evaluate their blood pressure immediately if shortness of breath and dizziness occurs. The American Council on Exercise reports that exercise with blood pressure levels above 200/100 can be dangerous.

Low Blood Sugar

Low blood sugar, otherwise known as hypoglycemia, is another common cause behind the development of shortness of breath and dizziness while exercising. During exercise, the body relies on blood glucose as a form of fuel -- and when levels of this compound are too low, signs and symptoms of hypoglycemia often become evident. Diabetics may want to consider checking their blood sugar before exercising to make sure that levels are in a safe range. According to the American Council on Exercise, diabetics should not begin an exercise session if their blood sugar level is less than 100 mg/dL.

Pulmonary Dysfunction

While the health of the heart is crucial for those who are participating in an exercise program, the lungs also play an important role. In fact, the lungs assist in the provision of oxygen to all parts of the body -- including working muscles. Those who have been diagnosed with a form of pulmonary disease, including chronic obstructive pulmonary disease, emphysema, or others may development shortness of breath and dizziness as oxygen supply is limited. For these individuals, supplemental oxygen may be required during moderate to intense bouts of exercise.