LTHR gains

After doing FF yesterday I had a question for everyone regarding their LTHR resutls from FF/HM.

What has your experience been on LHTR and how it has changed over time with your various FF attempts?

When I took my first ever test I got an LTHR from FF of 141. I saw very good and rapid gains in the months after this test though so I susepct I had the usual beginner’s low-ball results and perhaps 141 isn’t that relevant (that said I just checked my notes on that workout and it simply aid “Ouchie”, so maybe it was decent!).

After 10 further 4DPs and a couple of HMs I arrived yesterday at 158. My HR was stable between 158-160 for the whole 20min effort so that seems pretty reliable. I’ve no idea how much harder I could have gone, I had to lie down and couldnt move after the 1min sprint so overall it was ok…

What sort of changes have you seen? Have you seen it noticeably drop off after a period of de-training and rising again when getting back on the horse (bike) ?

Everyone is different etc etc, so there is no right or wrong of course, I’m just curious what people’s responses have been. I assume that you expect LTHR to drift higher with the right training, to some personal physiological ceiling.

Life gets in the way and since we’re not all being tested and measured as frequently or accurately as Rohan et al our results, both quantitative and qualitative, will be a bit anecdotal, but a lot of poeple here take this all pretty seriously so the anecdotes are good ones!


A quick edit for context: I just checked and few years ago when I was reasonably well trained I did a treadmill / lactate test and my lactate turning point (equivalent to LHTR) came out on 158, which is quite interesting. It’s hard to compare fitness then to now, but certainly when I did that first FF with the LHTR of 141 I wasn’t very fit and just getting back in training after bad illness.


Hi Leebo

Anecdotal it is. I can’t remember my first LTHRs but over the last year and a bit it’s gone 171, 171, 173 (FF), 173 (HM), 179 (FF - just before my KoS attempt so quite fit although took some time recovering from my Covid vax jabs), 182 (HM - 8 weeks post shoulder surgery and after 6 weeks of only Z1 and Z2 rides so far from super fit). My max HR for that last HM was 197 (on both my Garmin HRM and my Apple watch) and was just a steady climb to that number.

I’ve just turned 54 and while we all know that 220-age is a very rough guide for max heart rate my cardiac numbers do keep surprising me!


My LTHR seems very consistent over the last few years, across both testing and racing. It also aligns very well with RPE.

What does change (based on my training/beer drinking status) is the amount of power I can deliver at this LTHR…


Only thing I think I can really add is that it seems HM gives me “artificially high” LTHR results compared to FF…or vice versa. I just notice that I was getting high 160’s this year with HM, but FF dropped my LTHR to 163, and ID’d it as a weakness.

Given I’m classed as a sprinter, and struggle to improve my FTP/MAP, I’m not surprised. Frankly I wonder if both tests give me too much credit, based on how I’m doing in sustained effort drills.


Out of interest, how do you usually prepare for tests versus what your day to day routine is like? I ask because I was thinking just this very week that standard advice is to take a prep week and make sure you’re destressed, fully hydrated, rested, primed, etc etc, but then when we go through our training plans life still goes on and we’re not always fully hydrated, rested, primed, etc etc. Perhaps the tests arent giving you too much credit, perhaps that’s the real you without daily life in the way? Obviously it’s conjecture and I’ve no idea what daily life is like. Maybe you’re super chilled normally and super stressed before test day!?!

I think I’ve performed ‘best’ in FF where I haven’t had too much time to worry about it or put myself through a prep week. I find them difficult, get twitchy and more often than not cut it short and just get it done.

Ha! Interesting question. I can tell you FF provides me plenty of stress… :wink:

The biggest change(s) I’ve made in FF prep, in my vast year of experience with SUFF (happy anniversary to me), is that I pretty much do the “standard advice” prep week leading up to FF, but more importantly, I set the metrics for my upcoming FF myself, rather than “go by feel”.

After finishing a program, I approach FF as trying to attain a measurable % increase over the prior test. So rather than feel my effort through the four sections, I look at what I’ve focused on with the plan I’m finishing, and dial that % improvement into the FF - say I’ll set the effort to 110% in the video, and then just ride the “recommended” effort for FF in ERG mode based on that adjustment.

I’ve found, FOR ME, that takes a lot of the “how do I feel” guesswork out of the equation, heading into the test, lessens anxiety and stress, and improves my pacing. I know, “FF in ERG mode?!? Heresy!”. I figure I’m going in knowing what I’m facing, and coming out with a consistent, measurable gain. (Now, in practice, I’ll note that I’ve done it this way the past two tests, but in both of those efforts I dropped into level mode for the 5sec and 1min efforts, while riding ERG @ +10% for the 5min and 20min.)

TL;DR: I treat FF like any other SUFF ride.

I see the opposite. HM greatly under-estimates my LTHR, but FTP is spot on. I think HM is just too short for me to reach my LTHR. FF hits my LTHR no problem, as you would expect, and it agrees perfectly with my estimate from Training Peaks.

Same here. It’s always in the high 170s for me, although HM tests have always given a much lower number for some reason.

220-age is complete bollocks btw. My max HR is consistently 191 and I will also be 54 in a couple of months. It just means I have a relatively small heart that beats relatively fast.

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Yep, looks like both of us have hummingbird hearts!

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On my most recent test I say a saw a significant drop in LTHR. This was after about 6 months focussed on running and very little time on the bike. Drop was from 157 to 145 with FTP dropping from 209 to 184. Really struggled to maintain a hard effort during the test.

UPDATE 10 days later. Those numbers looked too low for my fitness level and were resulting in workouts that were just far too easy. I think lack of bike specific training meant I was mentally unable to suffer as much as I was physically able and delivered what was effectively a lazy session. Did half monty today where it is much easier to push to max and the numbers were 155 cTHR and FTP of 202 which make a lot more sense.

You aren’t alone, Colin. Last summer was my “running summer.” My distances went up and my times went way down as I helped my teenager prep for his first season on his high school’s XC team. I thought I’d crush the FTP measurement on my last #FF, but it went down instead.

Honestly, I don’t think it’s solely a function of cardiovascular fitness. I think I lost some of my cycling muscles+programming while I was away building my running muscles+programming. I think it helps to keep in mind that our numbers aren’t a reflection of our overall athleticism, our value as human beings, or our standing with our deities of choice. Our numbers are simply a reflection of how we’re doing on the bike at the moment.


It’s funny. Even tho running and cycling both use our leg muscles, they don’t use the same muscles in the same way. Cycling seems to help running fitness more than the other way around. With the higher impact, (speaking in generalities) running tends to use more strength while cycling tends to use more cardio. So cycling helps improve your cardio which can assist in building endurance for running, but the strength you build from running doesn’t contribute much to your cycling cardio.

I used cycling to help in my marathon training so I could do fewer high-impact running days, but still get a good cardio workout to help boost my endurance. But running usually just makes my legs more sore and tired when I try to do my cycling workouts. Maybe running helps make me a better cycling sprinter. I don’t know. lol. It mostly just helps me become a better triathlete. :stuck_out_tongue:


I’ve experienced similar. When I trained for a full distance tri my running was way better than the following year training only for a marathon. You could argue that total training volume was more in the tri year, but there was no way I could have done so much volume running alone. I’m tall and wide and so heavy with it, running consecutive days isn’t good for me (though Abi is definitely helping with that). But I can smash it on the bike between run days without issue.


I will also add something from my observations. I was and I am, above all, a mountain runner. But I have been training triathlon for several years and I have noticed that cycling training has definitely improved my descent from the mountains. Cycling probably made my knee ligaments stronger.


I found my number dropped initially and now has gone up again. It’s also very sports specific. For swimming mine is ~135bpm in warm water. Last winter in the reservoir (no wetsuit) 120 was a really good number to hit. Not possible to do intervals or warm up as too cold.

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One of the things I appreciated most about cycling in my younger (military) days was that I could do well on my fit tests w/o doing much run training - the cycling was enough to gut out a 2-3 mile run.

Later in life, for various reasons, I got into long distance running, which took its toll on me to where I can’t really run anymore for any significant distances. Thankfully, having jumped back on the bike over the past year, I’m once again able to do well on fit tests w/o having to train beyond time on the bike.

So totally agree, different training, different muscle recruitment, but I’ve found that cycling fitness feeds running fitness well enough for me.


Agreed I did a half-Ironman on 1 session swimming total (I have long arms anyway) and 0 running (kept getting injuries). It was fine till about mile 5 on the run. Was quite easily doing a good pace. Then it was actually my back that hurt. Made it but those last 8 miles running sucked. Pretty sure you can tough out any exercise up to about 45 minutes using just cycling fitness.

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