Is it vo2 max if your power drops below threshold?

For me, it’s all about the work/rest ratio. I find I need workouts where the time between intervals in a set is less than the intervals. This helps me raise my HR over consecutive intervals

So 30/30s and 60/60s don’t work. 90/60s work well.

I think the general recommendation is 2:1 work:rest - obviously varies a ton but generally speaking that seems to be the most common recommendation

otherwise known as “race cough”
great thing to have during COVID… go to the grocery store and get the worst looks.

You should take a read through this thread: Hard start VO2max intervals - #55 by adrian_r

There is a wealth of resources by some pretty smart people on the topic of VO2, and includes some sample workouts and objective/subjective metrics to go by

I’m sure someone has already brought up the good advice that 120% FTP is not necessarily the universal intensity to sustain VO2max intervals, and that FTP itself is an estimate of our max metabolic steady state, which is some theoretical moving-target construct that will change day to day and minute to minute.

The first priority in my opinion for ‘VO2max’ or high intensity interval training is that the work should be performed within the severe intensity domain, meaning above FTP / CP / MLSS / whatever protocol-specific estimate of max metabolic steady state that we want to use.

Saying intensity should be above sustainable steady state isn’t necessarily the same thing as saying power must be above FTP / CP / etc. Efficiency / economy can change during high-intensity exertion with increasing duration, such that O2 cost of power output changes. Coming up at our threshold from below can elicit a very different response (and feels very different, obviously!) than coming back down to our threshold from above. When we’re coming back down from a higher workload, having disrupted metabolic homeostasis, our max metabolic steady state (construct) could now be lower than our FTP number (protocol-specific estimate), See the recent narrative review from Maunder & Seiler et al which touches on all this.

That being said, if power doesn’t follow a strict proportionality with VO2, neither does HR. So maintaining eg. 90% HR doesn’t necessarily mean we’re at a consistently high %VO2max either. You could be starting too hard and drifting below true max metabolic steady state due to fatigue, and HR could remain elevated due to other factors.

Again, the priority (IMO) is accumulating continuous work duration in the right intensity domain. We each have to triangulate what that means for us based on the data we have available. Including sensations / RPE! Remember, our brains are pretty good at integrating all these sensory inputs and predicting how hard we can go! HR, power, VO2 are all sensitive to multiple factors, so as people have suggested, we might be best served by just kinda aiming for a wholistic sense of ‘hard’ for whatever interval duration we choose.

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If your HR isn’t going up, are you eliciting the same or similar benefits anyways because you’re getting time at intensity?

For example, 30/30s I can’t get my HR above 162 because I recover quickly. My max HR is roughly 178, so my target with 95% will be 169.

With Taylor for example, that’s effectively 30 minutes at 120%. However my heart rate will be mostly in threshold because of the 1:1 work-rest ratio. Or if vo2 max is the goal, should I start looking at more difficult ratios of work:rest or longer intervals?

Beta blockers will blunt heart rate response. But I believe diuretics, ace inhibitors, or calcium channel blockers will not.

(I AM NOT A PHYSICIAN), but do work in healthcare (PT). Ask your Physician just to be sure.

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