Common asthma symptoms are shortness of breath, cough, chest tightness, and wheezing.

Exercise, especially in cold air, is often a trigger for asthma. Aspirin can trigger asthma in adults who are sensitive to it. Laughing, crying, or hyperventilating can also trigger asthma. Tobacco smoke and viral infections are also possible triggers.

Each person's asthma triggers are different. Outdoor allergens like pollen may be triggers for some people. Indoor allergens and molds are triggers for others. Exposure to dust mites also triggers asthma. To keep dust mites under control, keep indoor humidity as low as possible and use special mattress and pillow covers. Ragweed pollen also is a potent asthma trigger.

Food allergies usually don't cause asthma. But children with food allergies can have asthma-like symptoms if they are exposed to their food allergen.

Sports played in warm and humid environments and those that involve shorter periods of activity cause the fewest problems. Swimming is a great exercise for children with asthma. Children with asthma that's well controlled should be able to play most sports without trouble.

Don't exercise outdoors in cold weather and on high-pollution days. Camping or hiking trips during the height of the pollen season are not advisable.

Wearing a scarf to cover the nose and mouth helps to warm cold air when breathing in. Cold air can be an asthma trigger. Pollution tends to be worse on hot, humid days, rather than in cold weather.

Many people with asthma have pets. Their pets may trigger asthma symptoms. To lower the chance of worsening symptoms or a flare-up, keep pets out of your child's bedroom, and off sofas and chairs. Brush and bathe your pets every week. Have your child wash his or her hands after touching your pets.