If you have exercise-induced asthma, also called sports-induced asthma or activity-induced asthma, it doesn't matter if you are training for triathlons or simply walking your dog: Exerting yourself in the wrong environment or in the wrong way can trigger an asthma attack. But by taking a few precautions and following your asthma treatment plan, you can still do the activities you enjoy. How Does Exercise Trigger Asthma Symptoms? When you exercise or physically exert yourself, you breathe harder and your body needs more oxygen. Exercise causes you to inhale air more through your mouth than through your nose. Normally, your nose warms and moisturizes the air you breathe before it reaches your lungs. But when you breathe through your mouth, your lungs inhale colder, drier air. Breathing in cold, dry air is the main cause of exercise-induced asthma. Cold, dry air can cause inflammation and swelling of your airway passages. This reaction makes it harder for air to flow into your lungs. The surrounding muscles in your lungs react by tightening and your body makes more mucus, both of which further block airflow. Asthma symptoms include: Chest tightness Coughing Shortness of breath and difficulty breathing Wheezing, a high-pitched whistling sound that happens when you breathe What Conditions Trigger Exercise-induced Asthma? Certain sports and activities are more likely to set off your exercise-induced asthma symptoms. These include activities or exercises that expose you to other common asthma triggers, such as: Air pollution: Swimming in chlorinated pools may expose you to air contaminated with chlorine and other chemical irritants. Skating or playing hockey in an indoor ice rink may expose you to air pollution from ice grooming equipment. Outdoor activities, such as running and soccer, can expose you to outdoor air pollution, such as ozone and carbon monoxide. Cold air: Winter activities and sports, such as skiing, sledding, or even building a snowman can expose you to dry, cold air. Dander: Horseback riding and ranch work can expose you to animal dander, another potential asthma trigger. Pollen: Hiking, gardening or performing other outdoor activities can trigger an asthma attack when pollen counts are high. Are Some Activities Better Than Others? You don't have to forgo all exercise and sports out of fear it will trigger an asthma attack. In fact, regular exercise is important to maximize your lung capacity and your overall health. Asthma and exercise can fit together. You just need to take a few precautions. The key to preventing an asthma attack is to not perform activities when it is really cold out or when the air quality is bad. Some types of exercises—when performed under the right conditions—are less likely to trigger asthma symptoms and include: Hiking Leisure biking Walking Swimming (assuming the pool chemicals don't bother you) Team sports that require short bursts of energy, such as baseball, football, and short-distance running Tips to Prevent Exercise-Induced Asthma Here are some steps you can take to lower your risk of developing asthma symptoms when exercising: Ask questions: If you regularly visit an indoor sporting facility, such as an indoor pool or ice rink, ask the manager of the facility about precautions they take to minimize indoor air pollution. Avoid using facilities with outdated equipment and poor ventilation. If you are interested in swimming, you may want to find pools in your area that use saline instead of chlorine to sanitize the water. Check the weather: Avoid exercising outdoors on days with high ozone or other types of air pollution. You can find this out by checking the Air Quality Index. It is available through your daily local weather or at www.airnow.gov. Dress smart: If you are a winter sports enthusiast, try not to exercise outside on extremely cold days. When you do exercise outside in the winter, wear a face mask or scarf over your mouth and nose to help warm the air you breathe. Ease into it: Warm up slowly with 10 to 15 minutes of stretching and mild to moderate exercise before beginning vigorous exercise. Talk to your doctor: Tell your doctor about all the activities you do, and where and how you do them. Together you can work out a plan that allows you to enjoy these activities and still keep your asthma symptoms in check. Follow your treatment plan: Take your medications exactly as directed. Your doctor may also recommend that you use your asthma inhaler 15 minutes before exercise to prevent asthma symptoms. You don't have to let asthma slow you down. By choosing your exercises wisely, following your doctor's instructions, and taking a few precautions, you can still do the things you enjoy.