Athlete Short of Breath in High Humidity

Patient: My daughter is a soccer player who is in very good shape. It is gets hot and the humidity is way up she gets a shotness of breath much more then she does normally. It seems that the high heat alone doesnt trigger it only when the humity is very high

Doctor: I understand your concern about this matter. Let me reassure you that this is normal, when hot and humid air is present the air is less dense, meaning that the oxygen molecules are more distanced one form the other.This would decrease the quantity of oxygen molecules in the same amount of air and would cause shortness of breath. On the other hand since your daughter is exercising, her oxygen requirements would increase and because of that she might feel short of breath and probably lightheaded. Her body would compensate for this increase requirement by increasing her heart rate and blood flow. I hope I could clear your doubt.