I'm currently dealing with my seasonal pollen allergies, and currently the right side of my nose is simultaneously blocked and runny. But when I start exercising, for example five situps, the blockage clears right up and I can breathe clearly. If I stop exercising, it comes back as suddenly as it left. Why is this?Apparently exercise causes your nasal membranes to constrict helping you breathe easier. After you exercise the effects wear off and the symptoms return. Membranes in the nose have an abundant supply of arteries, veins, and capillaries, which have the ability to expand and constrict. Normally these blood vessels are in a half-constricted or half-open state. But when a person exercises vigorously, hormone (adrenaline) levels increase. Adrenaline causes constriction of the nasal membranes so that the air passages open up and the person breathes freely. The opposite takes place when an allergic attack or a cold develops. During a cold, blood vessels expand, membranes become congested, and the nose becomes stuffy, or blocked. In addition to allergies and infections, certain circumstances can cause nasal blood vessels to expand, leading to vasomotor rhinitis. fitnessandwellnessnews.com, also make a valid argument. However, there's pertains less to the situation. Exercise can temporarily relieve nasal congestion. The increase in circulation clears sinus pressure and allows for easier breathing. An aerobic workout is especially successful in clearing congestion with its cardio focus. Although you may want to blend in with the bedding, movement provides the best relief. A stuffed nose is worse when lying down. Sinuses don’t have gravity working with them to drain cavities blocked by mucus. Sinus congestion is also loosened by increased temperature in the body’s core. A runny nose may ensue, which, although annoying, relieves sinus pressure and stuffiness.