Completed an interval workout tonight (Bontekoning) that stated a benefit of “By working very hard for brief intervals but only recovering for very short periods of time, these microintervals are extremely effective at improving your ability to sustain and repeat efforts well above FTP.” With 50 sec at 130% ftp and 20 sec rest, I found the rest just a smidge to short. So I would pause for 5-10 seconds to let my HR rate come down a bit making it a 25-30 second rest. Curious if I’d be better off decreasing the intensity. But genuinely didn’t have a hard time hitting the power goals. So thinking the training impulse from that power level is more important than the duration of the rest (within reason). I think I remember Nate saying it was better to pause in a podcast. Masters (old at 53) rider if that matters.
My unprofessional thought: if your legs can hit the goal but your heart can’t sustain the repeated effort then take the extra rest. We are not all created equal. TR workouts are general guide lines for the masses. You are better off finishing the workout than blowing up.
The purpose of this workout is not Power, its VO2 max. So it’s about training your body’s maximum ability to use oxygen for energy and to a lesser degree repeatability. There is no VO2 power, only your power at VO2 max. So no, you don’t want to add more rest, you’re defeating the purpose of the workout. You want to use whatever power allows you to finish all the repeats without skipping intervals or extending rest. You should find the rest too short, it’s not enough to recover and bring your HR back down which is exactly as intended.
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This situation is one reason many advocate to use resistance mode for vo2 max workouts. It is very hard to hold consistent power over a workout like this. It is natural that it may drop, as the number of reps increase.
I’d actually argue that a big part of these “non-traditional” VO2 workouts is focused on power.
If the only goal was to improve oxygen uptake and stroke output, another type of workout might focus on that a bit better.
These short, higher intensity intervals definitely have a power element to them that builds mechanical/muscular, and neruomuscular strength at high power, while still bringing you up into or near your true VO2 Max since they’re strung so closely together.
From a product perspective, I’d say that, like all other types of workouts, if you can’t follow along in real time, dial back the intensity until you can. If you have to dial things back too much (my limit is ~10%) then it’s okay to bail on the workout and pick something easy for the day to rest up and prepare for next time. There’s no harm or shame in that. 
What’s important with training is getting the right stimulus each day in order to get the right amount of stimulus each week. Adding rest between intervals is a sign that you’re not ready for that workout today, and that’s okay. You’ve got to listen to your body when it speaks. Smiply getting the work done at any cost isn’t usually the most productive way forward.
@bobsmail you passed a much harder VO2 workout last week, so it’s likely that your body just wasn’t ready yesterday for whatever reason. I did notice that your level 8.4 workout on the 15th was only rated as “Moderate,” and you rated yesterday’s workout as “Hard.” If you physically couldn’t complete the workout as prescribed, then I’d say that’s definitely more of an “All Out” effort. Telling the software that you completed that workout and it was only hard will likely result in an even harder workout next week, which it sounds like is the wrong move. 
It’s sooo important to be honest and accurate with your post-workout surveys, as it can influence your upcoming training in a major way. 
Let me know if this helps and if you have any questions. 
Great feedback and my RPE is probably off by one level. This is supported by the fact that I have never reported a max effort.
But in retrospect, I am pretty certain that I could have done this whole workout without the added seconds, because I succeeded in the first and fourth sets. I probably got into my own head and just wanted to see my HR stop climbing during the 20 second rest intervals. Had I done that I probably would have RPE’d it as very hard hard. And the workout did feel right for where I am in my plan. Legs were definitely tired last night, but are pretty fresh today with no DOMS.
It is really interesting that you compared it to the Coldblow +2 effort from a week ago because I genuinely found Colblow to be significantly easier than Bontekoning. I uploaded a screenshot from intervals.icu comparing the two and while the average HR and Power overall were very similar the impact on wbal was categorically different. Bontekoning intervals took me nearly to zero and the long recovery intervals were perfectly timed to fully recharge. By comparison, the Coldblow wbal indicates I was actually recovering during the last interval of each set… which matches with how it felt.
Not sure what any of this really means except that I probably need to HTFU on my hard intervals.
Me, personally? I’ll try like hell to do it, and if I just can’t, I’ll decrease the intensity a little and stick to the intervals.