Just done my 3rd ride with mine, on a wee hill loop (“Rapha-man” hill for my followers) with a steady 3-4m climb.

The powercal figures had seemed pretty odd previously (reacting to rate of change of heart rate it seems) and this got worse today – so heart rate goes from 135 to 165, power goes up to 380W, heart remains steady at 160-165, power goes down to 200W-odd.

I’m not sure if it’s any better than heart rate? I mean it doesn’t know my age, weight, HRM min/max, FTP, does it even read my speed from my Garmin?

If you want to measure how much power you’re putting out over a climb, forget it. It is all over the place (usually much higher or lower than actual power.) However still find over a ride of a decent length it does tend to average out to give a reasonable figure for NP and TSS that isn’t too far out (usually within about 10%.)

TA.

“Normalised Power”…and…toxic shock syndrome?

Unless you are climbing for a few minutes, it will not be reliable. I only look at powercal data with 30 second smoothing, and even then it is not that useful. I try and climb at 300 watts, but will see fluctuations even with constant perceived effort.

The algorithm uses changes on millisecond timings, so is very (too?) sensitive.

Normalised (read average filtering out zeros) will be a good reliable measure of your ride summary. TSS is just another measure of how hard the ride was overall. I don’t use it, just NP.

I think it assumes a sudden increase in heart rate would indicate an increase in power but that a steady high heart rate wouldn’t necessarily indicate a sustained high power.

Thanks, sounds like it’s not really for me.

*waits for cheap power meter*

Unless you are climbing for a few minutes, it will not be reliable. I only look at powercal data with 30 second smoothing, and even then it is not that useful.

I don’t even bother showing power if I’m using the PowerCal, too distracting. Find that anything more than about 3 second power, even with a proper PM, just has too much lag for me to effectively ride to. Funny to see the power jump up because of some hill that you’re over and past a few seconds ago!

*waits for cheap power meter*

How cheap do you want it? With some of deals out there you could get a Stages for around 500 quid. Hopefully the 4iiii will be sub 400.