Upper Limit to VO2 Intervals?

This morning’s workout was Taylor -2 (3 blocks of 14min 30/30s) and it was going pretty easy so I increased intensity to 125% of FTP and even then I had more in me.

Question is whether I should be shooting for total exhaustion in VO2 intervals or stay in zone? Because at 125% or more, I’m into Z6/Anerobic.

For reference, I just started Wk 2 of SSBII MV

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  1. It’s early in the block and it should feel a little easy.
  2. vo2 max work is a natural strength
  3. Your ftp is too low

Going into the second week you probably should feel pretty good, and the workouts should be engaging but shouldn’t blow your doors off. If the rest of your workouts feel correct then you could just be good at vo2 max work in relation to your current overall fitness level, and going into the third and fourth weeks will be telling if your ftp is a little low or not.

Also keep in mind all the workouts and plans are progressive, so you’re starting ‘easy’ and ratcheting up the intensity as well as increasing the fatigue.

Keep some notes on your workouts the rest of this week and going into next week, and if you really feel like they’re too easy bump up your ftp, or take another test.

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The problem is that there are two definitions of “vo2 interval”:

  1. Intervals in your vo2max power zone (i.e. zone 5 - 106-120% FTP)
  2. Intervals that force you physiologically into a high % of your maximal aerobic intake

Sessions can be both of those, or 1 but not 2, or 2 but not 1. For example, 30/30 intervals that get you to a high % of physiological vo2max would need to be at maybe 135-140% FTP.

In this particular case, the fact that the interval is 1 but not 2 is deliberate on Coach Chad’s part when designing the plan. It’s preparing you for the later weeks in SSB2 when the Tuesday intervals are 1 but also very much 2. The exhaustion will come!

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Its an easy workout, if you’re relatively strong at vo2max. You’ll end up bumping all the vo2 workouts, until you hit Spencer.


I’ve always been of the asumption that I have a Strong Vo2 Max so I do my workouts at a higher % of FTP.

Especially outside doing hill reps (Where there is a lot more motivation), 3 mins I tend to land around 130% and 5 mins around 125%.

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I did the same workout yesterday and I felt that it was easy too. I was tempted to increase the intensity but didn’t.

Threshold workouts are a lot more mental and taxing in comparison. lol