# Calculating LT1 and LT2 approximately without a blood test? **URL:** \ **Category:** Training\ **Tags:** polarized\ **Created:** [March 15, 2021, 8:57pm UTC](https://www.trainerroad.com/forum/t/calculating-lt1-and-lt2-approximately-without-a-blood-test/55533 "2021-03-15T20:57:15Z")\ **Posts on this page:** 20\ **Page:** 14
**Author:** ![Quaestor](https://avatars.discourse-cdn.com/v4/letter/q/8dc957/32.png) [@Quaestor](https://www.trainerroad.com/forum/u/Quaestor)\ **Post date:** [February 9, 2022, 6:41pm UTC](https://www.trainerroad.com/forum/t/calculating-lt1-and-lt2-approximately-without-a-blood-test/55533/280 "2022-02-09T18:41:12Z")
> [@Bigpikle](#): > > I did a big volume of z2 and z3 work the last 3 months. My z3 work was above my DFA-1a LT1 HR, but 3 months of solid work at 10-15hrs per week gave me a +30w increase in max 5 min power and +10w on my 20 min test last week. This is very encouraging, I’m on a similar path, but volume is very low about 4-5h a week right now. I will ramp it up once I can go outdoors. My target events are in July. That being said I started doing a bit of tempo, using HR limiter (160bpm). I had my first session on Monday. I was afraid it was going to suck, but It felt really easy on the legs and breathing. ![image](https://global.discourse-cdn.com/trainerroad/original/3X/5/9/59e607441687161a758fdb2495ea3154fd3fec80.png) ---
**Author:** ![tshortt](https://sea2.discourse-cdn.com/trainerroad/forum/user_avatar/www.trainerroad.com/tshortt/32/3100_2.png) [@tshortt](https://www.trainerroad.com/forum/u/tshortt)\ **Post date:** [February 10, 2022, 2:42am UTC](https://www.trainerroad.com/forum/t/calculating-lt1-and-lt2-approximately-without-a-blood-test/55533/281 "2022-02-10T02:42:00Z")
So if you got to 75% of 375W for VT1 wouldn’t that be World Tour Pro level? I asked in the thread on MAP but there is something I’m missing about these “translations” from VO2max to power. (Sorry for cross posting but wasn’t sure if you’re tracking the MAP thread) ---
**Author:** ![ojtCycling](https://sea2.discourse-cdn.com/trainerroad/forum/user_avatar/www.trainerroad.com/ojtcycling/32/64093_2.png) [@ojtCycling](https://www.trainerroad.com/forum/u/ojtCycling)\ **Post date:** [February 10, 2022, 5:14am UTC](https://www.trainerroad.com/forum/t/calculating-lt1-and-lt2-approximately-without-a-blood-test/55533/282 "2022-02-10T05:14:07Z")
Just catching up. Thanks for flagging. Reading the other thread it makes sense. I was (blindly) following Alan’s numbers. Sounds like 75% FTP for VT1 will be a good proxy. The ongoing education and learning on this forum is excellent 👍🏻 ---
**Author:** ![ChrisDe](https://avatars.discourse-cdn.com/v4/letter/c/c57346/32.png) [@ChrisDe](https://www.trainerroad.com/forum/u/ChrisDe)\ **Post date:** [February 10, 2022, 4:53pm UTC](https://www.trainerroad.com/forum/t/calculating-lt1-and-lt2-approximately-without-a-blood-test/55533/283 "2022-02-10T16:53:17Z")
Does the LT1 HR goes higher with training, or is it just the wattage that you can put at the same heartrate? ---
**Author:** ![kurt.braeckel](https://sea2.discourse-cdn.com/trainerroad/forum/user_avatar/www.trainerroad.com/kurt.braeckel/32/116719_2.png) [@kurt.braeckel](https://www.trainerroad.com/forum/u/kurt.braeckel)\ **Post date:** [February 10, 2022, 4:54pm UTC](https://www.trainerroad.com/forum/t/calculating-lt1-and-lt2-approximately-without-a-blood-test/55533/284 "2022-02-10T16:54:57Z")
> [@ChrisDe](#): > > or is it just the wattage that you can put at the same heartrate? The second one. ---
**Author:** ![Quaestor](https://avatars.discourse-cdn.com/v4/letter/q/8dc957/32.png) [@Quaestor](https://www.trainerroad.com/forum/u/Quaestor)\ **Post date:** [February 18, 2022, 1:13am UTC](https://www.trainerroad.com/forum/t/calculating-lt1-and-lt2-approximately-without-a-blood-test/55533/285 "2022-02-18T01:13:59Z")
> [@Bioteknik](#): > > Care to provide an example from published literature? [It was all here](https://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.887.695&rep=rep1&type=pdf) right in our noses. ---
**Author:** ![Bioteknik](https://sea2.discourse-cdn.com/trainerroad/forum/user_avatar/www.trainerroad.com/bioteknik/32/7721_2.png) [@Bioteknik](https://www.trainerroad.com/forum/u/Bioteknik)\ **Post date:** [February 18, 2022, 12:16pm UTC](https://www.trainerroad.com/forum/t/calculating-lt1-and-lt2-approximately-without-a-blood-test/55533/286 "2022-02-18T12:16:11Z")
The issue with that study is that lt2 wasnt reported, just tte at 88% vo2 max. With how they define lt1, it is going to overestimate it using 2 minute steps so it would have been beneficial to see the estimate for lt2 using the same protocol. If you look at the 30 minute bout at 80% of vo2max, even the high lt group was mostly around 2.5 mmol, which could easily be above lt1 for most people, or at least the very top of it if you want to say it is a range from baseline up to 1 mmol above it, assuming their baseline was 1.5, its still on the high side of that threshold. Then 88% vo2 was approximately mlss, so still a fairly normal distance between the two. ---
**Author:** ![Quaestor](https://avatars.discourse-cdn.com/v4/letter/q/8dc957/32.png) [@Quaestor](https://www.trainerroad.com/forum/u/Quaestor)\ **Post date:** [February 18, 2022, 3:55pm UTC](https://www.trainerroad.com/forum/t/calculating-lt1-and-lt2-approximately-without-a-blood-test/55533/287 "2022-02-18T15:55:05Z")
At the moment, I’m enjoying the new Skiba’s book, it has a ton of references and it has a good blend of theory and practice. He doesn’t seem to make any distinction between LT1 and LT2, his model of physiology has LT, CP and W’. It appears that in very well trained cyclists (w/kg \>4.5), the distinction of LT1/LT2 is useless and correlates ok with FTP. > **[Is the Functional Threshold Power a Valid Surrogate of the Lactate Threshold?](https://journals.humankinetics.com/view/journals/ijspp/13/10/article-p1293.xml)** > > Purpose: To analyze the relationship between functional threshold power (FTP) and the lactate threshold (LT). Methods: A total of 20 male cyclists performed an incremental test in which LT was determined. At least 48 h later, they performed a 20-min... The usual caveat is that all these LT analysis are conditional on the [testing methodology used](https://pubmed.ncbi.nlm.nih.gov/1459746/). ---
**Author:** ![tshortt](https://sea2.discourse-cdn.com/trainerroad/forum/user_avatar/www.trainerroad.com/tshortt/32/3100_2.png) [@tshortt](https://www.trainerroad.com/forum/u/tshortt)\ **Post date:** [February 18, 2022, 4:03pm UTC](https://www.trainerroad.com/forum/t/calculating-lt1-and-lt2-approximately-without-a-blood-test/55533/288 "2022-02-18T16:03:22Z")
> [@Quaestor](#): > > It appears that in very well trained cyclists (w/kg \>4.5), the distinction of LT1/LT2 is useless and correlates ok with FTP. He says this or _you_ are saying this? ---
**Author:** ![Quaestor](https://avatars.discourse-cdn.com/v4/letter/q/8dc957/32.png) [@Quaestor](https://www.trainerroad.com/forum/u/Quaestor)\ **Post date:** [February 18, 2022, 4:12pm UTC](https://www.trainerroad.com/forum/t/calculating-lt1-and-lt2-approximately-without-a-blood-test/55533/289 "2022-02-18T16:12:32Z")
> [@tshortt](#): > > He says this or _you_ are saying this? I’m paraphrasing, but Skiba is saying this and he is supporting it with the study I referenced. ---
**Author:** ![Quaestor](https://avatars.discourse-cdn.com/v4/letter/q/8dc957/32.png) [@Quaestor](https://www.trainerroad.com/forum/u/Quaestor)\ **Post date:** [February 18, 2022, 4:19pm UTC](https://www.trainerroad.com/forum/t/calculating-lt1-and-lt2-approximately-without-a-blood-test/55533/291 "2022-02-18T16:19:34Z")
I guess the revelation is that LT1 = LT2 for highly trained athletes. ---
**Author:** ![Bioteknik](https://sea2.discourse-cdn.com/trainerroad/forum/user_avatar/www.trainerroad.com/bioteknik/32/7721_2.png) [@Bioteknik](https://www.trainerroad.com/forum/u/Bioteknik)\ **Post date:** [February 18, 2022, 4:21pm UTC](https://www.trainerroad.com/forum/t/calculating-lt1-and-lt2-approximately-without-a-blood-test/55533/294 "2022-02-18T16:21:52Z")
I don’t have full access, but it is discussing ftp = lt2 in well-trained cyclists, but ftp is lower than lt2 in recreational cyclists. Cp is generally a little higher than lt2, as if you try to maintain power at Cp, you will be above Cp about half the time and experience increasing lactate concentrations. Cp is used because it is easier to measure, lt2 is still a bit of a black box while lt1 is fairly easy and reproducible to test. I have been trying out with estimating Cp with the 3 minute all out test, which is ime less taxing than the ramp test but is still quite demanding. Then i subtract 15 watts to use in tr for setting my workouts. Been working well so far, but vo2 work at 120% of that number is not freaky feasible since it is 20-30 watts higher than my 6 minute best. ---
**Author:** ![AJS914](https://avatars.discourse-cdn.com/v4/letter/a/919ad9/32.png) [@AJS914](https://www.trainerroad.com/forum/u/AJS914)\ **Post date:** [February 18, 2022, 4:23pm UTC](https://www.trainerroad.com/forum/t/calculating-lt1-and-lt2-approximately-without-a-blood-test/55533/295 "2022-02-18T16:23:53Z")
I listend to Skiba on a podcast recently (That Triathlon Show probably). I seem to recall him saying that LT1 wasn’t a factor for him. He also prescribes middle intensities. I have the new book on order. ---
**Author:** ![Quaestor](https://avatars.discourse-cdn.com/v4/letter/q/8dc957/32.png) [@Quaestor](https://www.trainerroad.com/forum/u/Quaestor)\ **Post date:** [February 18, 2022, 4:26pm UTC](https://www.trainerroad.com/forum/t/calculating-lt1-and-lt2-approximately-without-a-blood-test/55533/298 "2022-02-18T16:26:48Z")
After clearly defining LT as de rise in lactate of 1 (nmol)…Never talking about LT1, LT2, he goes to say, when talking about FTP: > it is strongly correlated with, and not significantly different from the lactate threshold. ---
**Author:** ![Quaestor](https://avatars.discourse-cdn.com/v4/letter/q/8dc957/32.png) [@Quaestor](https://www.trainerroad.com/forum/u/Quaestor)\ **Post date:** [February 18, 2022, 4:31pm UTC](https://www.trainerroad.com/forum/t/calculating-lt1-and-lt2-approximately-without-a-blood-test/55533/300 "2022-02-18T16:31:42Z")
…the quote is in page 37. I don’t know how can you interpret it different. If you follow what he is saying. He never makes a distinction between LT1 and LT2. And he defines LT clearly: > as de rise in lactate of 1 (nmol) How is LT2 defined? ---
**Author:** ![tshortt](https://sea2.discourse-cdn.com/trainerroad/forum/user_avatar/www.trainerroad.com/tshortt/32/3100_2.png) [@tshortt](https://www.trainerroad.com/forum/u/tshortt)\ **Post date:** [February 18, 2022, 4:33pm UTC](https://www.trainerroad.com/forum/t/calculating-lt1-and-lt2-approximately-without-a-blood-test/55533/301 "2022-02-18T16:33:34Z")
> [@redlude97](#): > > The paper for sure is only referencing LT2, its been around for awhile and discussed plenty. If there is another reference where LT1=LT2 I would be very interested. Yep, me too. That paper (among others I’m sure) demonstrates strong relationship between LT2 and FTP. > [@redlude97](#): > > My understanding is that skiba and many coaches havent really even considered LT1 for coaching since its been relatively easy to prescribe endurance work Agree, and I think it _also_ comes down to their belief that you don’t have to train _at or near max fax oxidation_ to improve fat utilization. IOW, all training at or under LT (and even certain types \>LT) improves fat oxidation. > [@Quaestor](#): > > I don’t know how can you interpret it different. If you follow what he is saying. He never makes a distinction between LT1 and LT2. And he defines LT clearly: I see what you’re saying @Quaestor and I’m not trying to “shoot the messenger” (you). I just think if he says LT1 ~= LT2 (for elites) I’m going to need to see more. Look at ISM metabolic flexibility paper and in WT Pro cyclists LT1 is not LT2. But as usual, language and methodologies…also inflection point or 2mmol/L or 4mmol/L? Need to see how Skiba defines. ---
**Author:** ![james\_a\_c](https://sea2.discourse-cdn.com/trainerroad/forum/user_avatar/www.trainerroad.com/james_a_c/32/59260_2.png) [@james\_a\_c](https://www.trainerroad.com/forum/u/james_a_c)\ **Post date:** [February 18, 2022, 4:35pm UTC](https://www.trainerroad.com/forum/t/calculating-lt1-and-lt2-approximately-without-a-blood-test/55533/303 "2022-02-18T16:35:20Z")
He doesn’t use LT2, he uses CP as the ‘second threshold’ ---
**Author:** ![Quaestor](https://avatars.discourse-cdn.com/v4/letter/q/8dc957/32.png) [@Quaestor](https://www.trainerroad.com/forum/u/Quaestor)\ **Post date:** [February 18, 2022, 4:46pm UTC](https://www.trainerroad.com/forum/t/calculating-lt1-and-lt2-approximately-without-a-blood-test/55533/304 "2022-02-18T16:46:47Z")
No, he first defines LT as mentioned, then in the FTP section he references that paper. However, what you say is not true, the paper doesn’t use just a cutoff of ~4nmol it uses the Dmax procedure ![image](https://global.discourse-cdn.com/trainerroad/original/3X/0/a/0a84227def9253bca25aed42522dbcfb4a34f3e3.png) In any case, it appears that Mr. Skiba is a bit sloppy in the LT discussion. ---
**Author:** ![Quaestor](https://avatars.discourse-cdn.com/v4/letter/q/8dc957/32.png) [@Quaestor](https://www.trainerroad.com/forum/u/Quaestor)\ **Post date:** [February 18, 2022, 4:54pm UTC](https://www.trainerroad.com/forum/t/calculating-lt1-and-lt2-approximately-without-a-blood-test/55533/307 "2022-02-18T16:54:33Z")
It seems that there’s a ZOO of thresholds and we could be lost in definitions. @BJRMD Mr. Bruce has a [nice article regarding this pickle](http://www.muscleoxygentraining.com/2019/07/first-and-second-lactate-thresholds-why.html) ![image](https://global.discourse-cdn.com/trainerroad/original/3X/c/7/c746bd1e8cf3a54f1716002dbc5672302378f7ba.jpeg) Seems like we have a nomenclature issue. ---
**Author:** ![Quaestor](https://avatars.discourse-cdn.com/v4/letter/q/8dc957/32.png) [@Quaestor](https://www.trainerroad.com/forum/u/Quaestor)\ **Post date:** [February 18, 2022, 4:57pm UTC](https://www.trainerroad.com/forum/t/calculating-lt1-and-lt2-approximately-without-a-blood-test/55533/309 "2022-02-18T16:57:58Z")
I don’t think what you guys call LT2 is what you think it is: ![image](https://global.discourse-cdn.com/trainerroad/original/3X/f/b/fb10dd8a5ddba86ac1bd6e510dc0f497a00c376f.png) Maybe listening too much Seiler is the issue. [Previous page](https://www.trainerroad.com/forum/t/calculating-lt1-and-lt2-approximately-without-a-blood-test/55533.md?page=13) [Next page](https://www.trainerroad.com/forum/t/calculating-lt1-and-lt2-approximately-without-a-blood-test/55533.md?page=15)