Thoughts on heart palpitations and max HR
First post. In the process of training for a 70.3 in June and am experiencing some odd things with my heart, predominantly when cycling but also occasionally on the run as well. For reference, I'm a 27 year old male, my resting HR is 40/41 and my max is about 198 (despite rough calculations suggesting it shouldn't be much above 190 but I appreciate that is a very generic assessment).
A couple of times recently I have been getting heart palpitations while on the bike and once during a run. In the case of the bike it happens after about an hour with an average HR of roughly 175, then it jumps up to 235 but resettles as before after about a minute. I also go slightly light headed, with some visual disturbances. Have been to the doc about it who, not surprisingly, didn't have any immediate answers. He was surprised to learn that I am able to maintain a HR of 175 - 180 for a sustained period of time, which in turn surprised me because that's not all that difficult for me. Am booked in for blood tests and an ECG in a couple of weeks. Until then I've been told to take it easy and don't train too vigorously. All the usual questions were asked - non smoker, light drinker, good diet, not on any sports supplements etc.
Wondered if anyone has experienced the same symptoms or has any thoughts at all??