Can you spend too much time in zone in a single workout?

Do you think there is a max length for a vo2max workout? (Same question could apply to other zones). As in after a certain accumulated ‘’in time zone‘’ There is a point of diminishing returns? I edited dade +3 and added two extra rounds of the same intervals (see image below). But now I find myself asking myself this question. Would I just be better off doing the prescribed amount of intervals and just add endurance till I reach 2h? Obviously if you’re unable to go any further then it’s time to call it a day, but I was curious what other’s have to say

If you’re able to spend that much time ‘in zone’ then I’d wager you aren’t working hard enough. Either your FTP is too low or you are a strong VO2 performer. Either is fine - but you’d likely be better served doing fewer harder intervals.

I think what I see there is a total of 18 2 minute intervals at 120% FTP. If you can complete that you should probably reduce the number of intervals and increase either their duration or the % of FTP


Oh I actually haven’t tried this workout yet though… ;p I did the normal dade +3 and just just finished it.

The main thing is if you finished okay, no adverser recovery affects. And were able to train as required plan… No Real harm done… The slight issue where are you to retesting FTP. If close fine the improvement from weeks of training (Great) or need to retest and set FTP higher and stick to plan. You are obviously managing VO2 max work well. I have done Dade +3 and managed it … well just. So hope what i say is what you need. You know how you feel and if its good… enjoy the improvement.

I think that vo2 max 20 min of intervals that elicit 10 min of vo2 max is a pretty good workout. Of course you can do more but why? It would be probably better to do 3 vo2 max workouts day by day to have some progressive overload. With threshold usually 75 min the resonable limit (depends of course on your TTE) . With SS something around 90 minutes. There are some bracket with reasoning in Kolie Moore webinar for WKO

If you’re really hitting it hard during VO2max intervals, 25-30 minutes is about the most anyone can do. If you can do more than that, either you’re not going hard enough, or the intervals are too short.


I don’t remember the cites off the top of my head, but the ideal amount of time in zone for VO2 work is 18-24 minutes. Anything over that and the recovery requirement diminishes the quality of the workout (and subsequent workouts). If you’re considering a workout like this my initial question is when did you last test your FTP? There’s a good chance an upward adjustment is in order. If you recently tested and used the ramp test then perhaps a more traditional testing method would help you dial in a more accurate number for you.

Ramp test planned for next week! But I was just interested in the in zone time.
You guys seem to say it’s about 20-25 minutes accumulated, that’s interesting and what I was looking for. Merci!


There is a great Tim Cusick/WK0 video that will give you deep insight into Time in Zone (TiZ) training for all training levels, including VO2Max.


I wonder the same thing too… I just did a workout with 5 minutes VO2max and 32 min (?!?) anaerobic.

I‘d think my FTP is too low, but it is set at 323W based on a 20 minute Zwift TT (yes, I know😊). My most recent TR ramp test puts me at 303W. (a couple of days ago). That would make that workout even stranger.

So… can you spend too much time at VO2max? In a recent podcast Coach Chad was saying 24-30 minutes at VO2max is the higher range…

I calibrated my power meter during the warm-up, so that can‘t be the cause for the weird numbers…

That’s an FTP derived/power based analysis. With anything over FTP, using general targets such as 120% is going to give general results.

According to many training zone charts, the “VO2max” zone is 90-100% HRmax; according to your ride file, your intervals were all ~97% HRmax. There is no HR value associated with the “Anaerobic” power zone.

Your ride was just fine. :+1:t5:

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