First Ventilatory Threshold and Fitness

Hi there, fellow Sufferlandrians

You know, I just listened to this podcast about cycling and performance and came up with the following questions:

  • Why is the aerobic threshold not typically taken into account when assessing fitness level/evolution?
  • Is it because its value is implicit or directly dependant on where our fitness level is at any given time (and characterised by other indicators such as VO2 max)?
  • If not, is it possible to improve the aerobic threshold alone while FTP, VO2 max or any other indicators remain fixed?
  • In such case, wouldn’t we be talking about being more efficient?
  • Isn‘t it desirable to be more efficient?
  • When and how train efficiency specifically?
  • Is it a good approach when our FTP and VO2 max are stuck?
  • How to measure aerobic threshold?

Sorry if I’m talking nonsense. I’m not expert at all in physiology but I’m always willing to learn about it.

It’s definitely not nonsense. But I’d guess the main reasons we don’t see it used are, 1 reliably measuring it in the field is difficult, and 2 IIRC it’s an open question whether VT1 and VT2 (for which FTP is proxy) really ever will move independently. And if they don’t l, testing FTP gets you everything you need and even if they do move independently to some extent, testing FTP still gets you a lot of what you’re looking for and you still have the challenge of measuring VT1.

Talking about efficiency, I assume you mean in the physics sense, which I think here means the amount of energy in that gets turned into work instead lost as heat. My understanding is that you get this by increasing your capillary and mitochondrial density through aerobic training. So any intensity of MAP on downward is doing the trick (although MAP works glycolitic systems too). Be patient and it’ll come. I would expect this to be reflected in both VT1 and FTP.

ETA, This is my take and I’m curious also to see what coaches think.

Also I do believe that you can get increases in fitness that are not reflected in FTP or maybe are, but are so subtle they’re indistinguishable from noise. This’ll be things like, what’s your max 5 min power AFTER doing 2500 kj of work.

Very interesting answer, it made further reflect :slightly_smiling_face:

By efficiency I meant specifically developing a higher power at VT1 by means of physiological adaptations.

Best regards,

I’d say the reason it isn’t used is that the first ventilatory threshold requires measurement using equipment we don’t have at home.

I think a lot of people resort to using lactate levels instead of ventilation and even that is prohibitively expensive for most people.

It’s also really confusing on line. The easiest explanations to find are not what I learnt at university. I think it would confuse too many people even if it was possible.

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But that version of efficiency is the same thing, right? The energy is either turned into work or lost as heat, and research has shown that the smaller motor units with mostly slow twitch fibers are more efficient than larger motor units. You train these up, you get better efficiency in both senses.

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