Heart rate vs Cadence

After two weeks only riding on Saturdays outside, 197 and 242 TSS, I came back to the trainer and did a sweet spot session.
My RPE was normal to low.
My power was good.
Heart rate was at threshold level, ±90% HRmax

After toning down my power to match the max sweet spot HR of 85% I finished my workout.

I compared that workout to the same workout twee weeks back and three weeks back and found that my cadence was 5-6 RPM lower the weeks before

Old RPM - 92-93
Last RPM - 96-97

Can my HR be explained by the increase in cadence or did I lose some fitness???

Probably because you were well rested.

When I’m tired, my heartrate is 10 beats lower than when I’m well rested


I have to say it is other way around, for me anyway, during warm up if I see my HR being higher than normal, I know this session will suck big time, and it does.

I noticed it very early so I dropped the power before it started to feel like threshold work.
When my HR is far off from 85% at 5-6 minutes into a sweet spot interval I know something is off, I know that much after 10 weeks of sweet spot intervals.

I just really would like to know what it is. I’m going to try my old cadence tomorrow see if that changes anything.

To clarify: This regards efforts starting from Tempo until VO2max

Well it is a good place to start messing around with effort levels, cadence and the effect it has on HR.

A jump of 2-3 RPM in cadence should barely affect you heart rate. There are some workouts where the text calls for a small cadence increase, on the proviso that it does not impact your heart rate more than 1-2 BPM.

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You were right!
I redid my ftp test and got 4 watts more :grin:
I got my powermeter in the middle of a training block so that was probably it.

You have a sample of 2 rides - very hard to make definitive statements based on that.

When I am tired my HR goes down as I cannot put the effort in to lift it up. YMMV. My cadence fluctuates anyway. Sometimes I spend more time trying to spin, others I just use my natural cadence which is about 76-80.

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Well I have a sample of 5 rides with that 15 intervals and I have concluded that my cadence did not influence my HR. I tried three different cadences during 3 workouts in different orders. 82-85, 90-92 and 95-98. HR variability was not significant in any of the workouts. Tho I must say somehow with a higher cadence it did tent to rise faster but leveled out at about the same. This did influence the results in the way you should expect. That being that the average HR did go up a bit. But after taking out ramp up part the HR in all intervals was the same with a standard deviation of only 1. No significant correlation between cadence and HR was found for me in this test data. The power difference was like 97% of the HR variance in SPSS.

And yes I really did throw in the data in SPSS to find what really caused this.
I almost never use the licence for school so I thought might as well try.

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Maybe I’m an oddball.

But if I do sweet spot intervals with 80 average cadence (say 3x15) my HR is high 140s low 150s.

If i ride them around 95 RPM my HR is high 160s low 170s.

Same wattage.

I’ve even tried a workout where I did the first intervals around 95 RPM and the last one in the low 80s and saw the same drop.


No you’re pretty much normal. Higher cadence = higher HR same power.