Heart Rate Variability (HRV), Threshold Training, Healthy Nutrition and More – Ask a Cycling Coach 354

Amber, Ivy, and Coach Jonathan discuss what HRV is, how it’s used in endurance sports, what it means if your HRV is low or high, what your HRV should be, the objective of threshold training and pro tips on how to get better at it, how to have productive conversations on sensitive nutrition issues with endurance athletes and much more. Join us live on YouTube for Episode 354 of the Ask a Cycling Coach Podcast and share this episode with your friends!

Tune in Thursday at 8:00am Pacific!

Youtube Live Video:

Topics Covered in This Episode

  • What is the point of over-unders?
  • Why threshold training is crucial for cyclists
  • Pro tips on how to get better at threshold training
  • What is HRV?
  • How Heart Rate Variability is used in endurance training
  • What does it mean if your HRV is too low or too high?
  • What should your HRV be?
  • Other ways to measure fatigue that are more accessible
  • Tips on how to recover better between workouts
  • How to have a conversation about food with endurance athletes you care about
  • Mixing group rides with your training plan
  • Picking complementary events for your goals


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I want to thank @IvyAudrain for the great comments on the live question about bike sizing. She hit well on the more nuanced issue of actual rider proportions as a key factor beyond the simple height guidelines. Her comments on stem length related to handling are spot on. @Jonathan hitting on Reach as the more important dimensional consideration is key for just about all bike sizing, at least initially. Coupling that with Stem Length and even Handlebar Reach are the finer details that all play together to give the final fit.

And the mention of the great sites was very worthwhile:

As I’ve mentioned in another sizing thread recently, there can be these cases where someone hits the borderline between sizing. Pure fit matters to a degree, but the Up/Down option can lean towards the handling results as well. Just another place where the details can be interesting and a challenge to nail down :smiley:


I just gotta say it’s pretty classic when you are doing a Trainerroad over-under workout, and you cue up the day’s podcast, and everyone is talking about how much over-unders suck and what you can do about it. :slight_smile: I eventually had to switch away from the lengthy discussion on HRV to some Psychadelic Porn Crumpets to make it through the final block, though. But 10 out of 10, would recommend!


Thanks so much Chad!!! Its a complex topic so unique to each person, glad I did okay!


As every Saturday, I was doing my 90 minute session. This week was Indianhouse -1 which is an over/under. It was good to hear from the team how hard it was going to be, the unders would not be the rest you want :grinning:. Talk about mental strength training.

“Come on man you can do this, @ambermalika, @Jonathan and @IvyAudrain are all telling you right now no one like these, they aren’t easy, but I am sure you can do it! :grinning:

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On surviving the unders, I find that the best way for me is to tell myself at the start of the under “Here comes the hard part! You will hurt and it will be hard, but you are recovering!”

Ironically, once I’ve made my peace with it they actually feel much better. I notice with some amusement that I usually feel better during the over (due to the delay in recovering).

Same thing with 30-30s for example. Often I feel strongest in the middle part of the working spike, as at that point I have fully recovered from the last spike and my body hasn’t fully realized it’s working again yet :man_shrugging:t4:

Over-unders are magical!

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I agree. I feel the same. I do enjoy them, more as it seems more mental than anything else.

Why did you leave us hanging again? Now all of us are wondering whether your grandma has led out your mom or not?!? :wink:
(This story still makes my eyes tear up.)

On the podcast you claimed that only Spotify has chapter markers. That’s not true, support for chapters/time stamps is not a Spotify-exclusive feature. Apple’s podcast client and the biggest third-party clients on iOS, Overcast and Castro, all support chapters.

Here is an episode of The Talk Show with chapters on my iOS podcast client of choice, Castro:

Here is how chapters/time stamps are accessible in Apple’s Podcast client:

Third-party client also support links for chapter markers (those are the white arrows) and custom chapter art (i. e. instead of the podcast’s default thumbnail/icon, you can select custom ones). You could use that feature to send listeners to particular references, a TR blog post or a special page that contains links to the references of a specific chapter.

Chapters can be added with freely available, professional software. Marco Arment, the creator of the biggest third-party iOS client Overcast and podcaster for over 12 years, has released Forecast, which he uses for his own podcasts.


This is an option on android as well, the popular podcast apps will show and filter chapters.

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This is really true for me. I am 189ish cm and what Ivy calls “all legs”, but my reach is not that great. Which means that the 60cm Supersix I’ve been riding has been causing me back problems. It’s a particular issue as the bikes I crave tend to have long reach and low stack. So now I’m looking at replacements and thinking I could even go to 56cm in some models if the seatpost goes high enough for my legs…


This is what I see in Downcast on my iOS devices.

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Only just occurred to me reading this thread that one podcast app reminds you of depression (Downcast), and another of wet cloudy weather (Overcast). They obviously think having “cast” in the name is worth it…

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Same here, although in the opposite direction. I am a giraffe and even though I am only 1,78 m tall, I need a size 56/large on road and mountain bikes. I had to pass up on a few very good deals, including a BMC Teammachine SLR01 with Rotor cranks for half price — size 54 cm. Bummer.

Felt a wee bit short-changed on the HRV discussion…it’s so much more than yet another golden bullet to tell you whether you’re fresh enough to go hard or not. Other than the daily HRV indicator (which needs properly trended & analysed to be of any use), there’s also in-exercise HRV which can provide live insight on aerobic and anaerobic threshold - I’m hoping that this is a data-field that TR can eventually incorporate

For those interested, there’s more on the in-exercise measurements here, including a custom data field for Garmin IQ (still in beta but looks promising) Muscle Oxygen Training: AlphaHRV - the first native Garmin DFA a1 data field


I agree that the HRV aspect of the podcast was lacking. I don’t know how well it is understood, but I do suggest the presenters touch base with an expert such as Marco Altini who has numerous publications on HRV and how to use it to determine readiness. In effect HRV is a trend analysis and without sufficient data to see what the trend lines look like knowing how to react to any given piece of data is difficult. For instance HRV4Training has a daily questionnaire and one question is are you sick today… believe me it likely can show it in trend view but it is nice to see it correlated on a graph. stopped listening to the Podcast due to frustration on this point. DFA a1 is an even fuzzier notion. It works for a certain group of people but again not everyone. Though I think it can be calibrated to give an individual an idea of where Aet 1 and 2 occur. It is still a work in progress but Bruce Rogers and others are doing some great work in the area.

My bottom line is that I think the presenters gave HRV a poor review and may have misinformed the listeners on the best options for using it, where it applies and what other things need to be assessed in addition to the raw data… and maybe a redo with an expert could really help out here.


Yeah, the challenge with handling the Reach related issues, is that the Stack is changed in conjunction with it. Sizing down leads to lower Stack, while sizing up leads to higher Stack. There is usually more adjustability with the functional stack with use of spacers under stems, and even the range of stem angles that are available.

But some combos lead to interesting setups with more extreme stem height and/or angles. It doesn’t really matter as long as the rider is properly positioned, but I’ve had some people revert from that good setup because they didn’t like the look of the final setup that was “right” for them.

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I’ll agree give that they didn’t have extensive experience with HRV it’s not a topic they should have included on the podcast unless they had an expert to discuss it with.

My issue with HRV is not so much with HRV itself but with it being just another cycling or endurance sport metric to track and try to comprehend. And it sounds like Ivy and Amber had the same feeling. Like what do I do with this.

As an amateur and not at the elite level there’s only so much data I’m going to look at and track. I feel like that’s part of the appeal for TR training plans. Pick a plan. Follow it.

So I don’t doubt HRV could be useful but I wonder if it’s getting buried in the piles of other data that cyclists look at and people really aren’t sure what to do with it or if they trust what it’s telling them

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@BikeTampa It is as you say one more thing to track… I think like anything, it depends upon the user and why they want to use it. For me it was mostly curiosity at first, then as time goes on and the data is better populated (better trends due to more data) it starts to make some sense and can inform me if due to stress noted in HRV that maybe a hard workout would be counter productive on that day. You need to still think it over but it is useful in that context to me. Then again I am not a pro athlete with years of finely tuned feel metrics where I know these things intuitively.

I’ve tried to track it a couple times but I was never consistent enough to track my heart rate first thing in the morning. I don’t know if whoop or oura track it but I don’t want to spend money on that.

Should add this site to the list:

Makes it easy to see by picture how the frame diminsions differ.

If only there was a moderator who liked to link to other threads on the forum… :-p Maybe this:

I agree. Here is his into to it:

and more info in his blog here:

I think this is right on. I think it can be a useful metric but can be hard to use well in that it has to be taken in the context of other things. Plus it can be tricky to measure consistently

If you assume a road bike with a carbon steerer tube with all things being equal (i.e. handlebar drop is kept the same and handlebars are still the same height off the ground) wouldn’t having more spacers under your stem be more comfortable then a slammed stem. So a smaler frame with more spacers vs a larger frame with a slammed stem. The thinking being that the longer the carbon steerer the more flex there is in the steerer tube absorbing bumps/vibration in the road. From research I was doing into my next bike (still undecided) I’ve heard people say the SL7 became much firmer in the front due to the recall with the longer metal insert (i.e. decreases how much the steerer tube can flex)

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