HR super high at end of SS intervals

I recently gave Sweet Spot Base another shot as I wanted to see if that was the right plan for me, and I found that the length of the intervals was killer to me on the trainer, even with a freshly tested (and lowered) FTP. As an example, my max HR (race-tested) is around 185 - 190 bpm, and at the end of the last two intervals of Antelope I was over 180, which seems really high for Sweet Spot. On one hand I primarily race XC with shorter/punchier climbs, so 10 minute steady state intervals aren’t generally all that relevant, but still interested to see what others think about how I should address - thanks.

If you reach that close to max HR for 10 min sweetspot intervals, youre FTP is way too high. This percentage of max HR, you reach at VO2max intervals.
That workout you did was pretty good but i think the adapations you will reach are into vo2max development instead of muscular endurance

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I checked your workout and I see that your HR went up at the end of last interval where the fatigue is at the top and at 110 cadence. I think this is so normal. I dont see any issues. Your cadence is way to high :slight_smile: (This is a good thing, i guess)

Good luck

In every interval he reaches over 90% of max heartrate (185) and it are just 10 minutes ss-intervals which are really small. This is vo2max territory

OK but he is at 110rpm. He pushes his cardiovascular system more than normal.

@KatuskaMTB what is your HR between 90-95 rpm?

@markbrouns, apologizes that I directly responded to you. I meant to answer first entry.

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Not a problem.

If i look further into it, you accumulated a lot of time in +90% max HR :muscle::muscle::muscle:

But to me it is not a SS wo. Try Wright peak -1 when fresh and see if you are able to finish it. If you finish, I am wrong :wink:

I can try that for the next attempt at an SS workout, but this is generally my natural cadence on the trainer, even for much lower % FTP attempts I’m in the ~100 range. Do you think spinning this high has a negative effect on my training / adaptations? Thanks.

That’s what I was thinking too - but I had literally just retested FTP recently (and actually had dropped it ~20 watts vs sticking with my previous value out of stubbornness…even though I wanted to), so surprised that my body gets so worked up with a ~90% of FTP workout

No, I don’t think so but when you do high cadence, you basically force your cardio which is normal.

Do 95 rpm and you will see that you will finish the workout so easily

Air temperature? Fans?


I usually have about 90% max hr (afaik) during longer sweet spot intervals (did Tallac +2) yesterday and reached 177-8 midway through the intervals at least after the second interval. I’m at the end of a whole training cycle and I don’t tend to fail sweet spot intervals. In fact, looking at my notes for yesterday, I marked it with an RPE of 6, which I find easy.

I wonder if my hr is just higher. It’s also getting warmer these days. I’m a short power kind of person, so it’s been a while since I had to do threshold intervals but they’re not usually a problem either. I test as TR schedules it.

Same here. It slowly creeps up, but after an hour with long intervals at 85-90% of FTP, I’m around 90% max HR. That does not feel anormal to me. I was looking at Deerhorn, which I did a couple of weeks ago, for example.

My guess too. Cardiac drift from core temperature increases. Op do you observe these HRs riding outside at sweet spot or near threshold?

I normally hit around 90% of max HR at the end of long sweetspot interval workouts.

I find when I forget to open my windows, my heart rate and sweat increase by a lot. This makes sweetspot feel like threshold.

Keep in mind fatigue also increases your heart rate and RPE, I had trouble doing 8 minute sweetspot intervals last week because I only slept 4 hours. The week before I did 3x20 without bailing.


Are you running fans? AC? What’s the room temp?

I actually have a massive fan pointed right on me (one of those big industrial metal ones). For my 70% FTP endurance work, I can hold 135-104 HR all day long, so it’s odd to me that when I’m at only 10 minutes on these 90-92% intervals I’m at/over 180, seems like much too high a jump.

Based on the FasCat / Coggins charts I’ve seen, Sweet Spot should end up around 95% of LTHR, which for me is more like ~170-172 bpm, which seems more in line with my first interval and then way under my last four. I wonder if this is just a lack of muscular endurance / fitness due to focusing on polarized over sweet spot all winter…

Tried this today (on a threshold workout), definitely kept my HR down a bit, but PE was certainly higher (but workout was still doable). Think this is great advice - thanks!


That’s OK. Not sure which workout you did but longer intervals will increase the fatigue and SS are not easy at all.

Try to stay that range until your body adapts, then you can gradually increase your cadence if you want to.

Good luck

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