Watt and HR variations

Hi.

Just wanted to share this.

Yesterday I did a endurance ride that lasted about 2 1/5 hours where I followed my trainer i ERG mode until 90 minutes had passed. The difference in Trainingpeaks between the first 90 minutes and last 60 mins was weird when I looked at the analysis. Although I had higher average watt the first 90 minutes (watt 175/hr avg 127) and lower avg watt the last 60 minutes 173 watts I had a staggering 135 avg HR. What I observe is that my power readings are fluctuating a lot when out of ERG mode and I makes med burn more matches.

I take with me that I might need to be more focused when out of ERG mode.

It’s not unreasonable to have your heart rate increase as a workout goes on for a couple hours, even z2. Hard to see the whole picture but 2 W isn’t much.

Yeah part of this could be cardiac drift as well. You are just fatiguing over time so your heart rate is going to increase throughout a workout at the same power. It is normal. It also is more likely to happen sooner indoors as your body will be hotter indoors.

You could just look at the 15 minutes just before you switched off erg to the 15 minutes after and compare those numbers. That would be a better comparison.