Heart Rate high for Sweet Spot

Hi, been a TR user for over 3 years now. Older rider. My max HR is about 171, and LTHR is about 166. When doing SS intervals my HR in the later intervals starts getting into the mid 160’s, while zone calculations suggest it should be mid 150’s. The intervals, especially once get over 10 minutes are hard, and I have to concentrate, but are completable, so I think FTP is right. Using a fan, but doesn’t seem to help enough. Not panting or breathing excessively hard. Should I be concerned and lower the effort? Any input appreciated.

Sounds like regular (expected) fatigue to me. Natural as your workout progresses. I wouldn’t be concerned.

Presumably you’re not using true power?

Consider more fans and extra/better hydration.

High temperatures can cause your heart rate to rise above what the exercise itself warrants, as the body tries to circulate blood to the small blood vessels close to the skin to get rid of excess heat.

I’d suggest an extra/more powerful fan.

As an aside, an LTHR of 97% of MHR sounds quite high - 86-92% is more common (at the higher end of this for trained athletes), although 96-98% does occur in some individuals. How confident are you that 171 is your true max?

Thanks for the feedback.

yes I am using “true” power, from a tacx, but was similar to stages (which I am not using for various reasons).

I cannot be certain of 171 as my absolute max, but it is a rate rarely reached and only all out on a hill, and at my limit. Although I know not good, 220 - age would be closer to 160. LTHR of 166 seems okay, as what I have experienced in 20 min tests, and was my Anaerobic threshold from a real VO2 test with the mask and all, although a few years ago. As an aside, measured VO2 max is pretty darn close to that from Garmin.

Would not be a problem if I did not see the HR during the intervals, just a little worrisome given age, and target zones.

I agree it should not be a problem, and heating/cooling is the problem, as not in the best of shape, and my HR does notably elevate on hotter outdoor rides.

Will see what happens when get to the threshold workouts!

@ralph2train it does sound high, and I’ve had the same experience recently.

Last winter (year 1 trainerroad) my ftp went from 242 to 275. This winter, starting 4 weeks ago, my ramp test said my starting ftp is 275! I’m 54.

I carried on with ssblv1 but now that I’m into the long 3x12 sweetspot sessions I’m coming unstuck. My max HR is 185. My 10 mile TT HR is 168. I did Geiger on Friday and was well into threshold at 164bpm, proof that I probably should’ve turned down the intensity really.

I guess there’s nothing wrong with doing a workout at threshold even if it was intended to be at a sweet spot intensity but it would take your overall plan out of kilter, I would think. Tonight is an over under workout, there is no way I’ll be on 100% given my level of pain on Geiger.

Hope that helps.

HI Darkgerbil, you sound like we are in similar situations. I also just did Geiger and while manageable my HR was higher than I am comfortable with - for me psychological as much as physiological. I looked at last year and had to turn down Warlow, which is up for me this week.

I will try changing the fan position, and either turn down the intensity or take breaks, or see if I can just survive it.

At some point it seems that doing high intensity (eg the overs) does not really increase my HR as already at maybe a set point even in the unders.

Something I’ve been doing as winter sets in here is open a window. The fan sucks some of that cold air in and over me. I’ve noticed a considerable ‘better’ HR performance since.

Thanks for the suggestions. I move my bike closer to a window and open it, and tilted my fan up and it definitely helped. Lowered HR by about 5 bpm.

Hardest part is not used to grabbing things (eg tv remote) with other hand!

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It’s always interesting to watch HR when I am in the middle of an effort and try to change the video, or have to respond to an urgent message or something… HR always up a few beats from just the change in focus (or the irritation someone dares message or call during my training time lol )

Evening all,

How “hard” is sweet spot for you guys? Relatively speaking, how far over AeT does the lower end (round bald /mountfield etc) of sweetspot take you?

These threads might help, a lot of discussion around this recently…



Cheers, I key word searched for heartrate and sweetspot but couldnt see the wood for the trees!

Was just a little worried (in a good way) that sweetspot was tempo heartrate

If you are well trained it should certainly start in tempo range for the first 5 mins or so and slowly drift up if you’re towards the middle of SS if you determined your LTHR as the avg 20 mins of a 30 min threshold effort

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The sweetspot segments earlier topped out at 148bpm (I’ve had a lactate test, AeT @150bpm. I trimmed sets 2&3 down 2%, but looking back I didn’t need to.

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Is it normal my heart rate is 178-180 during sweetspot intervals ?
Just finished my first sweetspot workout while hard it felt doable.
But it just feels like my Hr is to high.
Any thoughts on this ?

Do you know what your max heart rate is?

Have not really tested this but following the 220-age method it should be 195.

That method is very likely to be erroneous. It’s best to ignore that and use real data from your own experience.

Alright, so my max heart rate is 185 (even though I haven’t been at that rate in a year or so, but let’s roll with that, for now). During my last long sweet spot workout, Juneau-1, my max heart rate was 164, at the end of the very last interval. That’s 88% of max.

If your max HR is really 195, then 180 would put you at 92% of that.

Now, Sweet Spot, especially extended ones, are notoriously taxing, but if your heart rate is consistently near 180, that does seem a bit high, to me.

Not that there’s anything you can do about it other than keep working and get used to the effort. I’d be curious to see where others end up, as a percentage of max HR.

So as long as i can finish my workouts it is not an indicator that my ftp might be set to high.