I have a feeling that your all gonna say go to a doctor thats not right... but i feel fine so i thought i'd run it past you guys to see if its normal.
I cycle like a maniac for an hour a day, so am quite anaerobically fit. My resting heart rate is 36bpm and my max is 197bpm. I cruise at about 170bpm on my way to work but spin up to 190+ for overtaking cars and stuff. I'm 23, so its not totally weird to have such a decent range.
I seem to have dizzy spells, or borderline blackouts when i have been resting and then jump into action. My problem comes when i want to do something quickly; get up off the sofa, jump out a car, spring off the floor and run ect ect and my vision will go black/dark, i feel weak and dizzy and lose my balance, often ending up sitting where i began. This only lasts for like 3-5 seconds and bang my hearts up to speed and i am off on a mission.
Does anyone else experience this?