I have always been obsessed with data manipulation and since 2008 when I returned to regular cycling after the children were less dependant on me, I have kept details of every ride. I have logged distance, time, climb, max speed, and average/max HR. The latter figures were useful in helping my AF diagnosis, but the others were just used as motivation.
After every ride I would log the data and then produce graphs of average speed, climbing, distance etc. for the month, quarter and full year; this was only for road or trail rides, I logged rollers and velodrome rides separately.
Up until 2015, I was generally averaging 16 mph over a rolling 12 month period. It then started to dip slightly to about 15.5mph although until I entered persistent AF in February 2016, I thought I was just starting to feel my age. I continued to ride under the guidance of the cardiologist and my 12 month rolling average dropped to 12.9mph just after my first ablation in April 2017.
Three months after my second ablation the average started to climb again, hitting 14mph in August 2018 and 14.5mph in July 2019. I am now (September 2020) finally back to 15mph and can see further improvements daily.
In the graph below, the blue line is each day’s average speed and the red is the average speed of all rides in the previous year.
Since my return to health, the key difference to my riding is my max HR. Before I developed AF, my rides were at an average HR of 155, with a maximum in the high 170s (ramp tested maximum was 185). In order not to place too much strain on my heart I am currently on a self-imposed maximum of 163, although it is usually less than 160, and my average is around 135.
I am now wondering whether I was as fit as I thought before AF kicked in, and my high HR was not me working to my limits, but my compromised heart struggling to keep up with demand.