I have noticed that ~1 hour into a training session, my HR actually starts to DECREASE per a given power, either while on a steady power Z2 ride or a set of intervals. The decrease is on the order of 5-10 BPM and is seen by Garmin Connect as in increase in Performance Condition, but I am wondering if it really is. This happens on long rides outdoors as well. Any thoughts on why this is?
Thanks in advance!
I have observed similar things: I see it as warmup time.
Seems that I am warmed up the best after 1-2 hours of easy (but not too easy) cycling. Then I hit my best times.
Same. A good 40 minute into a workout and the engine finally hits its stride.
That’s pretty common. Interpreting heart rate data is not easy for this and many other reasons.
Look for negative decoupling.
Training Peaks have a few articles on decoupling - positive and negative
