> I don't know how true it is, but I've heard that some cyclists had/have to set alarms throughout the night so they wake up to do jumping jacks to get their heart rates back up above the "artificial" 15bpm that their training + cocktail of drugs has caused.
Even as a casual runner (top 20% in a marathon, def not competitive), I have had to silence low heart rate alarms on my apple watch because my heart rate regularly drops below 40bpm at night. When I’m in peak condition for a race, I’ve seen it drop as low as 30.
Professional cyclists have the highest VO2max of any athlete. Even without drugs I would be completely unsurprised if their heart rate gets to 20bpm in deep sleep.
Definitely some amount of it is natural, I'm even less competitive with running than you, but seeing my resting heart rate go down as you ramp up distances is a satisfying thing when you realize the hard work is paying off in a "tangible" way :)
I did a little more googling after the above comment, and it seems like another factor that (in theory) plays into the issue for the anecdote is that their blood can get thicker from doping. So it's a recipe of very low heart rate + extra viscous blood to pump that = danger.
Regardless, it's some pretty interesting/freaky stuff!
Even as a casual runner (top 20% in a marathon, def not competitive), I have had to silence low heart rate alarms on my apple watch because my heart rate regularly drops below 40bpm at night. When I’m in peak condition for a race, I’ve seen it drop as low as 30.
Professional cyclists have the highest VO2max of any athlete. Even without drugs I would be completely unsurprised if their heart rate gets to 20bpm in deep sleep.