Is there any risk in lowering your heart rate temporarily? My normal resting heart rate is around 50 bpm, but I can lower it to below 30 for well over a minute. Is there any medical risk to this? I feel kind of weird after a minute so I try not to go beyond that.
I'm having a very hard time believing you are actually doing this, considering I have very in depth knowledge of how the heart works.
But let's assume you are actually slowing your resting heart rate.
Yes, it's bad. Your heart pumps autonomously because your body regulates amount of oxygen in your blood. Need more profusion, your heart beats faster. If you are somehow consciously denying your body the proper oxygen it is demanding to function, then you are basically suffocating yourself.
But again your heart is controlled by your SA node, not your brain directly. Unless you have mastery over two autonomous functions, I believe you are mistaken.