Today, I was looking back at my HR during bike rides. My records go back to January 2010; I never recorded anything from my previous stand alone monitor. My max recorded HR at the time (ramp test) was 185, or perhaps slightly higher. I remember years previously at the gym, I couldn’t use the rowing machine effectively with a HR monitor as it would not allow me to break sweat; it would cut the resistance trying to keep my HR down to an arbitrary figure.
I discovered that there were heart spikes back from October 2010, from when I first bought the Garmin. Here is the heart trace from 19/02/2010. Max at 185 and average at 164. I am guessing that this is probably normal for me.
There was a trace for 23/01/2011, with a max of 196 and an average of 166. This was high but did not consider it an issue at the time. In retrospect, the second half is consistently high and there is no evidence of recovery on downhills.
There are a few more of these with high sections that generally correspond to long hills in the peak. The first seriously high one was 31/07/2011 with a maximum of 224 right at the end (downhill section). I don’t know how I didn’t notice this at the time.
None of this was causing any noticeable issues; in addition, my HR strap broke in May 2014 and I didn’t get a new one until December. The new one appeared to work perfectly until April 2015. With hindsight, this was not a failure of the strap, but possibly due to me entering persistent AF. On 06/04/2015 was the first ride where I was noticeably affected; although the HR is low (160) at the 50 minute mark, this is where I left my fellow riders and rode home slowly. I actually felt quite good while not pushing myself, and considered that I simply must be getting less fit.
Typical trace just before diagnosis on 06/02/2016 max 213 with average 174