Hi my age is 39 and for the last two years, I am on high bp medication. 2 years back I was regularly training in it with no issues. However, some times during hi it is used to feel out of breath but as soon as I stop and take a walk all turns normal. Nonetheless, I was always feared that someday this sob might go worst. One day after such out of breath experience and after talking 4 min. Rest I continued my hi it assuming it as a routine issue but sooner I restarted exercise I felt dizziness and got damn feared that today something would happen. I haphazardly rush for a home in fear and suddenly rapid breathing triggered. I got panicked and rushed for a hospital but doc found nothing suspicious in tmt, eco, ecostress, blood test, or any such test except raised bp. For 2-3 months I started turning winded even after few stairs, damn feared, and had fear of closed spaces. Situation recovered considerably since then; I do only outdoor fastwalk, for an hour, sometimes jog in chunks, do yoga and takes stairs with no sob but heavy breathing. My problems are that I am not able to run fast as when I increase my speed I feel that I am not able to breathe deeply (sometimes get sob for 10-15 seconds) but as soon I reduce intensity I get normal but heavy breathing. I used smart band and found my heart rate rise very quickly to 80-90% zone as I start increasing intensity. Pl, help me know why I am not able to run at my fun intensity.