VO2 training percent

To summarize the thread: no, it doesn’t. Good question! Number one rule: be able to finish the workout.


This is one of the questions I had for everyone. Recently I have steered away from an over focus on target watts and have instead switched my focus to RPE and HR as my focus metrics intra-workout.

The question that I have is, is the goal of training not to spend time in different zones, with HR being a great indicator of what energy system you are currently using/have used as well as where you are currently working, instead of relying on target watts? I’ve always been under the impression that the goal of a session, lets say a VO2 session for example, is to put your body into the VO2 training state, and that gauging HR is a great way to see if you are in that ‘zone’? This goes both ways too in that sense that you could also see if you were under training and doing Endurance work instead of say Sweet Spot work etc.

I understand that there are training adaptations and that naturally as you get stronger, you become more efficient and HR will drop when in those zones, but if you constantly perform an FTP test - every three/four weeks let’s say - then your HR zones will stay fairly constant with the increased load, and thus, the training stimulus in those zones is maintained.

Am I on the right path with that?

Make that, “harder is better, as long as you’re still training VO2max and not anaerobic capacity”.


Power is a better indicator of metabolic demand than HR.

Read the original question old timer.

Yes, the question is does it matter how hard you go, the answer scientists give to which is yes, at least up to the point that the intervals are too short so you are really training something else.

Sooooooo, if heart rate and RPE are fatigue dependent, would you say training VO2 would be fatigue dependent? :exploding_head:

I’ve recently switched to turning OFF erg on VO2 max intervals and go as hard as I can for the prescribed period keeping in mind the number of intervals I have to do. I use the power target as a guide.

On good days I end with NP at or above all the interval Targets. Bad days, I’m fading the last few intervals. But overall I feel like I’m getting the adaptations in the right zone and letting my body dictate how hard it is that day.


Good call. I’m going to use this approach. Thanks!

Isn’t NP supposed to be an estimate of the metabolic impact? Does it apply to VO2max intervals, which are supposed to cause cardiac adaptations?

NP is normalized power or that was my abbreviation for it. I’m just trying for normalized power in the VO2max range and go as hard as I can and finish the interval

Yes, but does that train VO2max as much as hitting the same average power? I’m not sure it does.

Now I understand your point/question. My average power is never more than a watt or two off NP for these intervals. Still doing them on the trainer so no coasting and no downhills. Just taking off erg mode

Aren’t you working the wrong system doing this. If you’re going as hard as you can then surely that’s well above vo2 max le; anaerobic or neuromuscular. Vo2 max should be worki5 the aerobic system.

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I am not sure it is possible to hold purely anaerobic for the duration of proper vo2 max interval. By going hard you are depleting anaerobic contribution and working purely aerobic.


Yes. I just hooked up my trial WKO and looked at a recent 1min@150% session. Turns into a 50/50 an/aerobic interval surprisingly quick.

Keep in mind that features like that rely on a well fed PDC. So there will be times you can’t trust some of the features.

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