Relationship between VO2 max and FTP

Bronzie

Can you predict your likely FTP if you know your VO2 max?

This was touched on in this previous thread:
http://www.bikeradar.com/forums/viewtop ... t=12608753

The relationship appears to be:
rider weight (kg)
x VO2 max (ml/kg/min)
x efficiency (%)
x %age of VO2 max that can be sustained for ~ 1hr
x energy contained in 1L of O2 (20.9kj)
x conversion factor (16.7W/kj)

What are the typical ranges for efficiency and sustainable %age?
Can either of these factors be "trained" or are you stuck with what you are given by genetics?

Alex_Simmons/RST

Efficiency is typically around 21% +/- 2%. it does not change much, we are pretty much stuck with that.

VO2 Max is about 50% genetic and 50% trainable but the level at which VO2 Max can be improved depends somewhat on how well trained you are to start with. An elite cyclist might see minimal to maybe 5-10% changes through the course of off season to peak fitness but a relatively unfit cyclist could see a 50-100% improvement in VO2 Max.

% of VO2 max that can be sustained at threshold is trainable. 70-80% of VO2 Max is pretty typical and some are capable of up to 90%, although that is much more rare.

Bronzie

Thanks Alex, that's interesting.

So a 74kg rider with a VO2 max of 54 could have an FTP in the range of:
- 185W (19% efficiency & 70% sustainability)
to
- 290W (23% efficiency & 90% sustainability)

Am I also correct in thinking that a typical VO2 max for a club-level racing cyclist is around 55?

Alex_Simmons/RST

Bronzie wrote:

Thanks Alex, that's interesting.

So a 74kg rider with a VO2 max of 54 could have an FTP in the range of:
- 185W (19% efficiency & 70% sustainability)
to
- 290W (23% efficiency & 90% sustainability)

Am I also correct in thinking that a typical VO2 max for a club-level racing cyclist is around 55?

Sounds about right.

VO2 Max relative does change with body mass though, so if you trim down through training, that number will tend to go up a bit.

Bronzie

Alex_Simmons/RST wrote:

Sounds about right.

OK, well the bit I'm having difficulty with is that I'm about average VO2 max, appear to have above average efficiency etc (to reach FTP of ~ 270W) and yet at entry-level road racing (3/4 cat) I'm only just about able to hang in there.

I reckon 300W is really the benchmark (talking predominantly flat races here so outright power rather than power-to-weight), and anything much over 300W will put you in contention.

Does this mean that most of the others lining up at the start have above average VO2 max capability? :? Am I competing against genetic freaks?

Alex_Simmons/RST wrote:

VO2 Max relative does change with body mass though, so if you trim down through training, that number will tend to go up a bit.

I hover around 73-75kg most of the year. At 6'2" (188cm) I think I'm pretty lean already. Certainly no "muffin tops" around the waist. I'm certainly not "pro" lean, but compared to some of the guys on the start line, I look pretty trim.

Anonymous

No, just freaks!

Alex_Simmons/RST

The best predictor of performance is performance itself. I wouldn't worry about VO2 Max for that purpose. Even so, VO2 Max of 60-65 ml/kg/min is not uncommon in lower level Cat racing.

FTP/kg is a better physiological indicator. 3.6 W/kg would probably struggle in Cat 3. In some parts there are plenty of Cat 4s who are 4W/kg or better.

If your FTP/kg is similar to your competitors but you are struggling, then it's not your FTP/kg that's your problem. It's more likely to be other factors.

Bike racing is a tough sport.

edited to correct factual typo

Bronzie

Alex_Simmons/RST wrote:

The best predictor of performance is performance itself.

Yes, probably getting a bit too @nal about it all. I was hoping the PowerTap would answer the eternal question "Why am I such a shagger?" but I think I've ended up with more questions than answers perhaps. It's like watching an episode of "Lost".

Alex_Simmons/RST wrote:

If your FTP/kg is similar to your competitors but you are struggling, then it's not your FTP/kg that's your problem. It's more likely to be other factors.

Well, it's impossible to know this info for sure without frog-marching everyone to the scales, just a hunch that I'm lacking the 30W that would make the difference.

Can you expand on what other factors could be in play?

Alex_Simmons/RST wrote:

Bike racing is a tough sport.

+1 - at entry level, I can think of no other sport where the required standard is so high. There is no "jogging along at the back of the field" option. Once you are dropped, you may as well pack and save it for another day - most of the time you don't even get placed if you are outside the top 15.

Edwin

Bronzie wrote:

+1 - at entry level, I can think of no other sport where the required standard is so high. There is no "jogging along at the back of the field" option. Once you are dropped, you may as well pack and save it for another day - most of the time you don't even get placed if you are outside the top 15.

I couldn't agree more! I've trained more then ever before this year, raced every week from March onwards and only got two places and a measly five points. That's why I'm starting to take some interest in the technical stuff, so I can hopefully train smarter instead of harder.

FWIW, VO2 Max is usually given as ml/kg/min - I had mine measured at the University of Birmingham and got a value of 64, but I'm rubbish.....

Alex_Simmons/RST

Edwin wrote:

FWIW, VO2 Max is usually given as ml/kg/min -

Er yeah, that's correct - my bad. ml per litre doesn't make much sense now, does it

Alex_Simmons/RST

Bronzie wrote:

Can you expand on what other factors could be in play?

- Anaerobic capacity

- Skills, nouse and awareness when bunch racing

- knowing how to ride effectively with the minimum amount of energy expenditure (there have been TdF stages completed on less than 100 watts average)

- Motivation

- Aerodynamics

Often whenever I've been unfit, such as starting out from a longish layoff, I race well, because I have to in order to survive. You work out which are good wheels to follow, you choose good locations in the bunch, you use corners and changes in gradient to your advantage, you position yourself sensibly well ahead of difficult sections....

Bronzie

Alex_Simmons/RST wrote:

- Anaerobic capacity

Ok, so you can presumably train anaerobic capacity with Level 6 intervals, but is there a genetic limit to anaerobic capacity which presumably varies between individuals? Are some individuals better able to deal with lactic acid build up than others?

Alex_Simmons/RST wrote:

- Skills, nouse and awareness when bunch racing

Hmm...........yeah, certainly room for improvement in bunch positioning. I need sharper elbows! :twisted:

Alex_Simmons/RST

Bronzie wrote:

Alex_Simmons/RST wrote:

- Anaerobic capacity

Ok, so you can presumably train anaerobic capacity with Level 6 intervals, but is there a genetic limit to anaerobic capacity which presumably varies between individuals?

I'm not sure how much is due to genetics but there is definitely a difference between individuals.

If you happen to have the book, Training & Racing with a Power Meter, then look at pages 189-192 to see how this is demonstrated by examining two riders that ride an individual pursuit in about the same time but do so through a different balance of aerobic and anaerobic energy production.

Bronzie wrote:

Are some individuals better able to deal with lactic acid build up than others?

Yes, some manage to sustain a higher concentration of blood lactate than others. Whether this correlates with improved performance I'm not certain right now but it's power at LT that matters, not what the BL concentration is at LT.