The Rise Of Gyms Offering Performance And Science Lab Grade Tests... Data Means Little Without Insight

I had a convo with someone last week who had a previous VO2 test months ago at another gym. It got me thinking about the rise of gyms offering lactate and VO2 tests for their members.

Yet if you looked on social media I would say the majority of S&C coaches and PTs struggle still with defining zone 2, or many still struggle with the role of lactate or defining lactate thresholds. So I’m always interested when I hear of VO2 max and lactate threshold testing packaged up to sell memberships, up sell personal training, or give clients a sense of “elite performance coaching”.

***From someone who offers this service and who has turned a few people away from testing for various reasons.

I don’t really care what I’m telling you as long as I make you think it’s important so I can sell it as a solution - Social media, 2025.

Data means nothing without insight, we have to be careful that it isn't performative theatre wrapped up as 'science' to sell you things you don't really need, or that they don't truly understand.

VO2 max testing is a prime example of this. I have run lots of VO2 max and lactate tests over the years, and whilst I enjoy the exploration, I am honest about its utility.

The point of testing for me, for whom it is appropriate, is to attain a greater level of understanding of what is happening across training intensity. Too often though the VO2 number is the sell.

Cool. But...

1) VO2 max itself is rarely illuminating and is not a standalone predictor of performance outcomes and 2) The test is often botched and methodologically flawed.

Ultimately, if you’re only looking for VO2 max, then you’re missing things that probably matter more especially when the point is to help someone get better... and that’s the point, right?

What can you look at during a VO2 test?

Thresholds and deflection points like CHO/Fat crossover. Ventilatory thresholds/gas exchange thresholds can help identify capability across power/speed (VT2 for example can highlight when ventilation can no longer sufficiently compensate for the rise in CO2).

Economy & efficiency - economy for example tells you about the cost of maintaining a given submaximal speed or power e.g. someone who runs at 4:00/km pace using less oxygen (better economy) will outperform someone at the same pace with the same VO2 max but worse economy. VO2 max testing should be integrated with other useable markers i.e plotted with HR responses & perceived exertion.

To be fair here, the literature itself is also not immune to confusion and so it leaves little hope for most of us trying to get some guidance. Especially with lactate testing. There is no universal agreement on threshold definitions, and the terminology is often inconsistent across research papers and testing.

For example, ventilatory threshold 2 (VT2), anaerobic threshold, LT, OBLA, >4mmol.... These could all mean the same thing or all mean different things based on what paper you read. There are pros and cons for why you might choose one and all of these may impact your training zone definitions.

Chris Froomes GSK data shows how they all can vary quite a bit based on methods, yet they could all be interpreted to mean the same thing i.e. the point where lactate starts to accumulate exponentially / anaerobic threshold. The point is, when you go down that road you need to know your shit. And you either a) use it all the time and consistent with your methodology and comfortable with its limitations or b) you are up front about single test limitations and the issues with looking at things in isolation.

This inconsistency is rarely addressed though, yet it critically undermines the validity of any testing or zone based programming derived from such assessments (IF that’s even done). This also assumes that methods are solid too and coaches are reading the data correctly. I fear most aren’t even averaging breathing frequencies over 15s sampling windows or they are running ramps with huge jumps in power in short time frames.

The bottom line.

VO2 and lactate testing are useful tools when used appropriately if you’re discussing the above, if not, it becomes scientific theatre.

“But.. but.. we use it as a measure of progression!”

....VO2 tells you about oxygen consumption capacity not capability in context, so if progression is what matters, it’s a poor marker. VO2 also often plateaus or can even decline despite performance increases and so it can be misleading if that is the thing you’re chasing. The real value should be in the ‘what happens next’. VO2 & lactate testing data is only as good as the person interpreting it.