But patients with asthma had a significant decrease in lung function when they were dehydrated, even when they weren't exercising. This occurs because dehydration causes airways in the lung to constrict, making breathing more difficult. Doctors at UT Southwestern Medical Center at Dallas say hydration is important for everybody, but especially for those who have asthma. Drink plenty of liquid before exercising, and replenish your fluids during exercise. If you wait until you're thirsty, your body is already lacking fluid.
Water is the best fluid for hydration.
Avoid caffeinated beverages such as tea, coffee or cola and alcoholic beverages when you're trying to remain hydrated because these are diuretics, making you need even more water. Other Topics Health Watch is intended to provide general information only and should not replace the advice of a medical professional. You should contact your physician if you have questions about any of these topics.