Why does my nose run when I exercise?
It’s called runner’s rhinitis and it’s a common malady for exercisers, particularly those who run outdoors. When you engage in cardiovascular exercise, you typically begin to breathe faster and take in more air through your nasal passages. If you’re outdoors, you are also breathing in pollutants and irritants, and one way for your body to prevent these contaminants from reaching your lungs is to produce mucus in your nose, which will trap these agents.
Consider spraying some saline spray in each nostril before you go for your next outdoor run. You can also try a non-drowsy antihistamine if you have no health or medicine contraindications. If the dripping is persistent or really bothersome, consult with your doctor who may refer you to an allergist.