VO2 Max workouts and Adaptive Training

I seem to be one of those people for whom some of the VO2 Max workouts, like 30/30s, are too easy just don’t get my heart rate up.

I did a cursory read of some of the long VO2 Max discussions, tried a couple of the TR podcasts, but I’m still confused about how to modify the plans/workouts. From what I understand, these are the options for modification, but I don’t have the knowledge and time to figure out how to best adjust things. There’s a lot of info embedded in many posts, but it’s difficult and time consuming to tease out a high-level summary/consensus.

Here are the options I understand and my challenge to figuring out how to best modify both the individual workout but also the overall training plan:

  1. Increase intensity (to all out?)
    • Wouldn’t this bump into Anaerobic or Sprint Zones?
    • Would this torch the muscles in my legs too much?
  2. Choose workouts with harder starts and decreasing power (like Rattlesnake)
    • Could try, but it’s a little cumbersome to find these types of workouts and how do I build a planned progression after the first Rattlesnake workout?
  3. Increase duration of intervals
    • I think this may make sense and guessing this is what the plan progression builds up to, but I read in one of the posts that the 30s intervals improve repeatability so not really sure if I’m losing some of the other goals of the workout besides getting the heart rate up (like learning how to quickly recover and repeat, …?)
  4. Reduce duration of rests
    • I really have no idea what the impact of rest is on the workout. I see some are half as long (for the quick intervals), some are the same, and some a longer than the interval duration. Don’t know what I’m doing here.

Another challenge is that with 1 scheduled VO2 Max workout a week, I’ll spend most of the phase trying to dial in what’s right for me.

With the complexity of VO2 workouts, I think this is somewhere that AT could really add value. (I guess this is where having a coach is really helpful).

It would be great if AT could recognize that VO2 Max workouts aren’t getting my heart rate elevated enough and then automatically adjust the workout in the plans to something more appropriate…increasing intensity, change the workout to one with longer interval duration, or choose workouts w/hard starts, or something else based on whatever the planned progressions are trying to achieve. Even if AT doesn’t have the ability to recognize I need something different, it would be great to have a switch in my profile to indicate my HR is slower response and I need a different type of VO2 workout, and then have a different set of VO2 workouts populate in my plan for me.

In the meantime, I think I’ll try some of the longer duration workouts in my plan, either by jumping ahead in the plan or seeing if there’s an alternate workout suggestion that’s a longer interval.

Happy to hear thoughts and ideas on plan modifications and progression. I’m doing LV SSBase 2 right now, training for a 5-day MTB stage race in May.


If you feel able to I would push that wee bit harder and ignore the power target to train the VO2max. There’s a vO2max thread on the forum somewhere and this Kolie Moore podcast is linked too and he makes some interesting points about VO2max and how some folk never really get to it at a certain power level.


why not select an alternate workout with slightly longer work intervals and or higher progression level?

baird+3 is too easy? if it is your ftp probably is set too low

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What’s your VO2 PL set at?

As HLab says, I think the answer is to change to “all-out” intervals, but in the three, four, of preferably five minute range. I wouldn’t change the short-shorts to “all-out” personally.

Find one of the workouts with the right structure (Nebo maybe, though I’d try find something with 6min rest) and just go for it.

See how your Power lines up with the target and how your breathing and HR response line up with expectation.

Thanks! It looks interesting, I’ll bump it to the top if my list to listen to.

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I have similar problem. Leaving aside topic which VO2max intervals are the best, here is how I found my %FTP for VO2max.

Sample workout, Bashful: 5x1min at 125% FTP, 3 sets

  • Turn workout intensity immediately up, even above what you think is sustainable for whole workout but can do single interval. Note, this is workout intensity, not FTP %.
  • With each interval, keep lowering it by feel so you can complete each interval.
  • After 1st set is done, choose whatever workout intensity level felt hardest but sustainable for other sets

Now you haven’t lost week with too easy workout and can calculate FTP percentage for VO2max workouts. Let’s say workout intensity 120% felt appropriate. It would mean for you VO2max FTP percentage would be 125% x 120% = 150% (i.e. 1.25 x 1.2 = 1.5).

Note this value is interval duration specific, higher with shorter intervals, lower with longer. For me personally, sweet spot is 2min interval where TR workouts are properly doable as they are.

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Just rate it honestly and AT should do the rest. I am in the same category (I like short shorts as I can always get them done. If you rate it a 1 or 2 things will ramp up pretty quick.

Only my inference but I think AT is looking at an expected range of response. Maybe 3 or 4 for the workout here depending on how you find VO2 relative to other types of workout. To say “this was too easy” I think your survey therefore needs to be a 1 or 2 and see what you get dished up next!


Main constraint here is that alternates typically have the same workout structure, when athletes just don’t respond to short/shorts.


50/50s already feel very different from 30/30s and 30/30s alternates gives 60/30-60 and even 90/30-90 intervals


I’d say the power is too low then. With the short/short type, increasing the power and/or shortening the rest ratio may work, such as 30/15s, 40/20s, 20/10s, 60/30s. Whatever keeps your HR up during the rest intervals. The other option is going longer in the 4-6min range, with or without hard starts. Whatever form gets your HR up and keeps it up as long as possible will give you the best results.

Here’s a good thread about VO2 max.

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I think this might be a problem as folks are confused (myself very included) what the goals of a VO2 max workout should be. If you’re literally trying to raise your VO2 max I’m of the understanding that interval duration seems to be the most effective. 30/30s are a great warm up to more effective VO2 training later down the line, that’s my understanding. I much prefer the on/off nature of 30/30, 30/15 etc but I can tell without a doubt that pushing interval time out to 2, 3, even 5 minutes is probably the “magic” fish out of water feeling you’re trying to induce.

If your workout goal is repetitive efforts near VO2 max, maybe the shorts/shorts have their place. I’d try to hard start VO2 max workouts and see how you respond.

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Yes, in long run AT does its magic. But for shorter block it is too slow. At the beginning of this year, did 3 week “refresher” block (from RRRHV specialty plan first half) after many months of Z2 stuff and before starting SS progression block. I had to start already with Breakthrough alternative and continue next two weeks with Stretches (PL 1.2 → 4.9 → 6.8 → 8.4). The block would have been over before AT has chance to dial in.

Knowing your VO2max ballpark %FTP is just a good way to jump to good starting point.

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Very interesting episode. Just finished listening and had some questions, so maybe @empiricalcycling could clarify. I know he hates cookie cutter plans as every athlete is different. And in the episode he says HR isn’t the best metric for VO2 max workouts. With that in mind, how are the short short type of workouts always bad(compared to long)? Maybe I missed it, but did he go over studies that showed longer continuous intervals always better? Wouldn’t the thought that every athlete is different mean that some people would respond well to short shorts? I just did a workout with 4 sets of 20/10s for a total of 6 minutes of the on portion, and was definitely huffing and puffing for the latter part of each interval. I picked 10s as the rest specifically to shorten it. With longer intervals, I really struggle to go longer than 3 minutes. So I figured getting 6 minutes of “Tiz” for lack of a better word, is better than say 4x3min continuous. Or am I shortchanging myself? I keep my cadence up during the rest as well so I’m going for 9min total with a high cadence. Seiler had a video about short shorts with various studies showing effectiveness (posted in the hard start thread), and even had various professional cyclists submit their own workouts doing these intervals. So I’m just wondering why the short shorts are considered bad by Kolie.

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I think the best way to get AT to assign you the optimal workouts is to keep choosing ‘Stretch’ or ‘Breakthrough’ alternates a few times, until you hit a point where these are sufficiently tough. That should bump your level to a place where AT assigns you appropriately challenging workouts. Even if it takes it 2-3 weeks to get you in the right place, it should be OK to go after that. Even as your FTP changes AT is pretty good at dialling in a new progression level.


FTP could be off. But generally, VO2 Max workouts in the plans tend to be easier for me, not getting the HR up if I stick to the power.

I haven’t tried Baird+3 this season yet.

I had some concerns for over-training last Sept so backed off, and then started on MV Base using AT around Nov. FTP dropped 30W (~14% :confounded::sleepy:) and another 9W drop after SSB1 and a couple weeks of illness and recovery, but figured I’d leave it to ease back into things. Haven’t done any structured VO2 workouts until a couple weeks ago for LV SSB2. And started with Taylor -3 followed by Taylor -2. I bumped the intensity for Taylor -2 by 5% but was still was manageable.

Bluebell is up next for me, but I’ll consider Baird +3 to see where I am.

Looking forward to the new FTP estimator in a cpuple weeks when my next ramp test is due. Curious to see where it lands me as I don’t ramp test well when I don’t get any VO2/anaerobic workouts in.

VO2 PL is at 2.9, but I think it’s a little low from manually bumping my FTP slightly and some pl+qaying around with time off. I had support bring my VO2 workout back up what it was before messing around with things so my next VO2 workout is Bluebell at 4.5. I don’t really feel like my VO2 “system” is at a 4.5 level though, I just feel like the workouts aren’t the right ones for me. Or I need to bump the intensity. Just worried about overdoing it, especially when in Base phase, which I have a tendency to do. I really like trying to go as hard as I can as long as I can :smile:. But maybe it’s good to push it a little more and see where my limit is.

I have the same trouble. I do better at getting HR up by choosing longer intervals and not the shorter on/off.

Just push the PL to try and see what you can do. I pushed the PLs when you look at my increases noted below.

AT kept pushing short intervals which didnt result in hr getting to where it should be. The ramping went 3.9>5.7>6.3>7.3 FTP reset 5.9>6.6>7.3 Again short on/off but power definitely going up…135% of FTP was the highest workout.

I selected the next workout, Spencer which is 7.5. 3 minute intervals at 120% FTP. I just find the longer intervals work better for me to get my HR up there in zone. It worked better then what AT kept picking.

I do find there are benefits to the short on/off workouts from the muscular viewpoint but they dont address the HR for me that well.

Thanks for sharing that! That looks like a nice, measured way to zero in on an appropriate power level without over-doing it or cooking oneself too early. I’ll give it a shot.

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I’m mid session and will reply in a bit more thoroughly, but just chiming in with listen to the EC pod and make sure you are riding with a high cadence to shift the load from the muscular system to the cardio system (in super simple terms).

TR has great progression in VO2 but you might just be suited to skipping the short shorts to speed the process.

I took a look at the VO2 Max workouts in TR, and looks like once you get past ~PL 4, the number of 30/30s workouts is reduced, even 30/30 floats. The first 1min interval is introduced at PL 3, and 3:30/3:45 intervals come at PL 3.5. So seems like 30/30 is primarily used to ease people into the longer VO2 intervals, and 30/30s at higher PLs bump the intensity to 125-130% FTP. The short-shorts seem to progress to 40-50s or 30/15s as well.

So I guess while I feel like my VO2 capabilities are low/weak, it’s beyond the beginner/intro level and it does make sense to push the PL progression as a few people have suggested, and if workouts seem too easy until AT gets me to the right level, then just push the intensity and/or use hard starts, or use svens’ approach to identifying at what %FTP my VO2 max is.

Thanks all for helping me work through this. Guess it was probably obvious to many, but I needed to work out some of the logic of pushing the progression and ditching the need to do the prescribed 30/30s.