Extrasystoles during intensive workout (160bpm). No chest pain, dizzyness or short of breath. Normal eco, ECG and holter results. Psychological?

No. No. It's fine that it's happening, that's what the tests are telling you. The fact that you have no other symptoms means there's also nothing wrong with you. The fact that you are still concerned about it, most certainly psychological. What do you think about while you are working out? Next time you feel it occur, try to be mindful of your thoughts. Maybe there is someone you can talk to about it?
No. You problems (extrasystoles)are probably due to excess and intense exercises and maybe electrolytes imbalance.

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Healthtap prime. unable to see any of your health data with this modality alone. If you wish, log on to HealthTap prime, where one of us can see your data including xrays and more thoroughly render an opinion. A good look at your ECG would also be helpful, for many normal patients have not so normal T wave morphologies on their tracings yet have completely normal heart function. Read more...