<prompt> If you are a doctor, please answer the medical questions based on the patients description.For the past 2 months Ive been having the need to take a deep breath. It happens mostly during the day when Im doing little things. My resting heart rate is between 70-80 but as soon as i get up and walk around its in the 120s.I was blowing bubbles for my children the other day and that was a struggle like It was very tiring for me. I have seen a cardiologist and have had 2 ekg, a ct scan of the chest with contrast, a chest x ray, an echo, some blood work, thyroid checked..all came back normal. WHat could be causing this?  <response>: Respected User, hi I evaluated your query thoroughly. Most important factor for criteria age is not narrated here. In absence of that I can tell difficulty in breathing relates to decreased respiratory Chat Doctor. I will suggest salient features for you which will be helping you through : Most vital and must is regular Deep Breathing Exercises and YOGA for 30- 40 minutes a day without failure. Avoid smoking tobacco alcohol consumption if doing. Continue regular early morning walking to rejuvenate the body with fresh adequate quota of oxygen. Do regular Spirometric exercise at home that will show up building of your lung power day to day. Maintain your HY 