Low Power, Low Heart Rate (HR), High RPE?

Either my power meter is broken or something is up with my body.

I was having trouble holding zone 2 power.

Sick or overly fatigued?


What kind of load (TSS) did you do the past week? How does that compare with the week prior (i.e. how big of a ramp did you undertake)? How well/how much time did you allow your body to recover?


Your body will also react to mental stress, caused by work, studies, for example.

I had a pretty hard period at work a year ago and had similar symptoms: I was not able to do any demanding workouts during that time. For several weeks I did just short and easy workouts and the situation got better eventually.

If you use a dual-sided pedal PM, and one of the batteries runs out or it isn’t connecting properly, it can just display power from one pedal which would be 50% of what you’re actually doing.

But that would be really noticeable, so I suspect either calibration issue or simple fatigue is more likely the cause.

Whats TSS like in the weeks leading up to this vs. historical norms? are you over your 6 week average?

Whenever I get this its late in the season and its straight up over training for me personally. If this repeats after a few workouts take time off, copy a recovery week and resume with the recovery week.

This may be completely off for you but I had a similar issue with chronic inability to drive heart rate in workouts. The numbers were down a bit but I could not get higher heart rates no matter how hard i tried. I saw my doctor and he recommended magnesium. One week later… problem solved. Turns out athletes lose quite a bit while exercising, and more so if you drink caffeine and/or alcohol. Made me take a look at my diet as well. Consult your physician first.

Also wouldn’t affect his ability to raise his HR. If anything, HR would be higher at lower powers if one side of power meter was malfunctioning.

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Early signs of over training. Pay attention to your rest/recovery.