Shortness of breath during exercise is your body's way of telling you a number of things. Before you start any exercise program, especially if you're overweight, haven't exercised recently or have been diagnosed with a medical condition, you should get a complete physical exam from your doctor. Discuss various forms of exercise with your doctor that provide a comprehensive workout to gradually increase your endurance and stamina.
One of the most common symptoms of shortness of breath is rapid, shallow breathing, according to Dr. Moira Fordyce, writing for The AGS Foundation for Health in Aging. Rapid breathing means you're not getting as much oxygen as you should. Your body needs adequate amounts of oxygen for optimal function. A feeling of light-headedness is also a symptom of shortness of breath that can be caused by exertion or exercise. The light-headedness or faintness you feel is because your cells aren't receiving adequate amounts of oxygen. When cells are lacking or starved for oxygen, they cease to function as they should.
Overdoing exercise when first starting a routine is one of the most common causes of shortness of breath while exercising. Your body needs to generally increase duration and exertion when exercising in order to increase aerobic benefits, burn fat, and increase muscular endurance and stamina. Trying to do too much too soon causes excess stress on the lungs and increases the heart rate as the heart and lungs try to maintain adequate oxygen- and nutrient-rich blood flow to the muscles.
Medical conditions such as heart disease, chronic obstructive pulmonary disease -- also known as COPD -- emphysema, asthma, or being overweight or obese may make you feel short of breath while exercising. When your body isn't healthy and you exercise, you place extra strain on the heart and lungs to supply the body's cells, tissues and organs with blood carrying oxygen and nutrients such as proteins that enhance muscle function. Smoking may also cause shortness of breath, due to the decreased function of the lungs smoking causes.
Your doctor will advise you on the types of exercises you should start out with, as well as the duration of your new exercise program. Follow your doctor's advice in regard to type, duration and number of exercises you start out with to help prevent shortness of breath, light-headedness and possible falls or accidents. By slowly increasing your duration and exertion levels, you can help your body benefit from stronger lungs, a stronger heart and stronger muscles.
Start off with a slow walk, either on a treadmill or outdoors. Walk several times a week to start, beginning with a duration of 20 to 30 minutes. Gradually increase your speed and distance until you notice a change in your ability to walk farther, faster and longer. Gradually add other forms of exercise to your routine, including strength training, stretching, and both low and high-impact aerobics to your weekly exercise programs.