The dizziness and shortness of breath happens several hours or sometimes the next day. This is after a moderate or intense exercise. I can exercise at a low intensity for a long time without any problem. For example I walked 5 miles in 90mins on Sunday and had no issues. Then on Tuesday I walked 2 miles but half of it was on high hill. I was feeling dizzy and out of breath the following day. I have tried drinking enough water/electrolyte, eating sugar and breathing properly. This has not helped. My bloodpressure during these episodes is usually a bit lower around 104/64 or similar. Otherwise I always have ideal bp. No other health problems. I am a 40 year old female.