I had to recently do Baird+2 and I don’t understand the goal except to induce a lot of fatigue: Log In to TrainerRoad
Baird +2 is 3 sets of 5x90-second intervals at 120% FTP where recoveries between intervals are 1 minute long and recoveries between sets of intervals are 6 minutes long.
My understanding of vo2 (from the emperical cycling podcast (watts doc 23 i think) is it’s all about oxygen uptake improvements and you target this with highish power but the key is high cadence to drive breathing up.
I can only manage 2.5 minute intervals with high cadence (110+) and then I need a good 5 minutes or so to recover.
there is no way my legs would survive doing Baird+2 at that cadence at that power with those number of repeats with short recovery (I managed around 100rpm cadence). My HR certainly didn’t get anywhere near my vo2 zone. But my legs are fried.
What if I told you that what we traditionally think of as “VO2 workouts” aren’t really working the VO2 system (and that it doesn’t matter). Steve Magnus has a great blog about this.
But anyways, a workout that is common amongst milers is 10 x 400 @ mile pace with 1 minute recovery. You recover fast enough and by the time you get back to VO2 it really is inconsequential. But that doesn’t mean they are a waste of time… rather you are training at race pace or faster. And that is a good thing!
All that said I think one of the things that is often overlooked is the recovery periods that are often too long and too easy.
The workout goals description that @mtbjones shared has some solid info.
I like where @Jolyzara is going as well. These ~60-second intervals can be highly productive in that you can accumulate a lot of time at a high workload without feeling an overwhelming amount of global fatigue. It’s more local, as @trebor mentioned, resulting in fried legs.
@Twowkg, these don’t have the same exact goals as traditional VO2 workouts, where the intervals are ~4 minutes long, and if you tried to ride a workout like this with max effort intervals, it would likely crush you.
Some prefer to do traditional VO2 workouts out of ERG mode, and I can understand that, but these on/off style workouts are better done in ERG mode, in my opinion. Again, the goals aren’t necessarily to get to true VO2 Max and sit there, but to spend a significant amount of time in that training zone with little bits of rest mixed in.
The main confusion point here is training zone titles. VO2 Max is a physiological state that we might try to reach during some traditional VO2 Max workouts, but it’s also the name of a training zone that spans from 106-120% of FTP. Not all workouts with intervals in that power range have the same intentions.
These are kind of like strides for runners, which are becoming extremely popular across the board. There’s certainly an aerobic benefit from doing them, but there are also neuromuscular benefits that can be highly productive.
@eddie thanks for taking the time to reply and that is very informative.
If I play back what I interpret from the response, these workouts are geared at getting used to working at higher loads, muscular endurance and repeatability? And not directly (I appreciate there may be indirect benefit) increasing your vo2 max?
What physiological changes are they aiming to achieve? I’m definitely fatigued at the end
Maybe I phrased it weirdly, I don’t mean to ride the first interval of each set as maximally. Just to ride each set maximally. Since there is a very significant variation in what individuals can do above ftp having a set % has issues.
Adaptive Training will take care of that for you. We’ve got enough workouts in our library to ensure that if you fall on either side of the bell curve, we’ll get you a workout with the right power targets.
It sounds like they were trying to ride through the intervals with a specific type of form as advised by Empirical Cycling for their take on traditional VO2 workouts (high cadence, etc.).
@trebor I’d ride these like normal threshold intervals – seated with a cadence that supports sustained power output. For me, that’s somewhere in the mid-90 RPMs, for example.
i feel the need to clarify, they didn’t advise me that info on their podcast was for what you’ve called “traditional” vo2 max training, which are targeting a very specific physiological adaptation
I hear you! Sadly my new trainer just has the zwift click cog thingy … so no shifting. I’ll probably have to sort that by replacing it with a cassette at some point.
I also dislike and I think I may have injured my self when ERG (at least on my trainer) goes from high resistance at say 320w to absolutely no resistance at 90w. I prefer to be more in control of the resistance change.
I won’t shift, I’ll simply adjust the resistance on the pc (laptop) its very easy but I think you can do that (control resistance) too on the android app. Its probably not as easy though with sweaty fingers, I’ve a keyboard protector on the laptop.
My knees hate that. I’ve hurt them more than once banging/grinding in erg. On the other hand, once I finally learned my lesson, I became much better at VO2 max intervals because I focused on that fish out of water thing instead of trying to keep the erg pedals spinning.
It works better for me being in resistance mode but its probably something to do with the quality (or lack of) ERG on the Suito. With ERG, my knees hated constantly hated trying to battle the ‘spiral of death ‘ at say 120-130%, and the sudden release of resistance at the end of an interval. Its also pretty random how it controls ERG in a interval and will to a lesser degree back of resistance too much at random points and I find myself spinning like mad only for the exact opposite a high resistance grind a few seconds later. I always seem to pick up an injury when I try ERG again, I prefer being control of the resistance with the Suito at least.
i feel the need to clarify, they didn’t advise me 
that info on their podcast was for what you’ve called “traditional” vo2 max training, which are targeting a very specific physiological adaptation