VO2 Max test

What started with a casual post on Facebook about a VO2 Max Assessment concluded the next day with me being thrashed, momentarily, on a running machine with a mask measuring Oxygen and CO2, a heart rate monitor and with Pete Rees kindly capturing the whole thing in still and full motion video….

What is a VO2 Max and why should we care?

Wikipedia defines it as:

VO2 max is the maximum rate of oxygen consumption as measured during incremental exercise, most typically on a motorized treadmill. Maximal oxygen consumption reflects the aerobic physical fitness of the individual, and is an important determinant of their endurance capacity during prolonged, sub-maximal exercise.

I see it as the size of your engine in terms of cubic capacity. Are you a 1.4 litre super charged engine or a 2.2 diesel? It measures how much fuel (or oxygen) you can you take into your engine (lungs) and process.

Why do the test?

I paid to have a VO2 Metabolic Profile assessment primarily to understand more about my body and to help architect a targeted training programme for this year. The main drive behind this was to shift the needle in readiness for the OCR World Champs and World's Toughest Mudder.

I headed along to True Zone in Bristol for my assessment, which included the following:

  • Personal training zones (heart rate and power)
  • Aerobic and anaerobic threshold
  • Threshold and functional threshold power
  • Your level of fat burning efficiency and fuel mix
  • Guidance on training to maximise your time

In theory, knowing more about all of that would help me to better understand my engine, so that I can tune it and get the most out of it.

For the previous year my training has been, how you say, ad hoc! I would go for a run when I felt like it and the distance would be determined by how much time I had to spare divided roughly by 8 minutes (8 minute miles being my steady running pace). However I thought there must be more to it and, whilst training for the Cranky B****d Virtual 5km race, I noticed a jump in performance. Suddenly I was running 7 minute miles when out training and breaking 6 minute miles in races… could there be something there I wondered, could that high intensity training being improving my race performance?

Putting mask on

What does the test consist of?

VO2 tests vary throughout the UK, so I can only talk about the one I had and my experience of it. The session consisted of a steady warm up on the running machine before fitting the mask and heart rate monitor. The mask itself is only there to measure oxygen and CO2, so didn't restrict my breathing at all. Once fitted the test began, working up from a gentle walking speed to a 16.5 kph running speed, all at incline level 1. If that wasn't enough, from that point onwards the incline gradually increased up to level 6, at which point I had reached my limit and signalled that by waving my hands around like the guy out of Team America. Following on from that was a gradual decreased in speed and incline back to a walk and a gentle cool down. All in all, I was probably on the running machine for about 15 minutes and probably only 2-3 minutes was at peak effort.

It is not a particularly difficult test and the maximum speed is determined by your race speed, for example a 10km race time.

After the session we had a chat about the main findings. The main thing I took away from the feedback, pending the formal report which is due in a few days, was that over the years I had built a strong aerobic core from my steady state training runs in the aerobic zone. However my anaerobic performance needs to be improved, significantly, if I wanted to shift the needle.

This was evident when I ran Hell Runner Hell Down South the following day. I was super conscious of the fact that I struggled on the hills where, to maintain race pace, you need to be operating in the anaerobic zone…. I wasn’t and, shamefully, had to walk up a few of the hills on the day, losing time and places (Ed: It would be hard not to struggle on those hills. Scott still came 29th out of nearly 1,500 people, so I don't think all is lost 😀 ).

The other interesting fact was that my VO2 Max was actually relatively low at around 43. That surprised me because I have run some races which gave predicted VO2 Max in the region of 55. According to some sources on the internet a VO2 Max of 43 is average but nothing special. Now I don’t proclaim to be a spectacular runner but my race performances have mostly been top 10%, so I would consider myself to be an above average runner. Therefore, if it was all about VO2 Max, then surely this wouldn't make sense.

Run test

Is race performance all about VO2 Max?

The bottom line is that VO2 Max is predominately genetic and you may only be capable of increase yours by a small percentage. There is actually more to performance than just VO2 Max. Thankfully other factors come into play! The assessment I undertook was a VO2 Metabolic Profile, which also factored in heart rate and fat burning (determined from the CO2 monitor) rather than just focussing on VO2 Max.

The standard "Training Zones" that you often see published in various tables or calculations only really work for a small percentage (circa <10%) of the population, so to truly understand your training zones you need an assessment like this. From here you can adjust your training accordingly.

I now have a fair idea what I need to work on, so I am now going to factor in at least one high intensity anaerobic session per week, ideally two, and then I shall have another VO2 Metabolic Profile done in three months to gauge the improvement. I will also take advantage of a 45 minute consultation with Andy Wadsworth at True Zone to discuss my results and training goals. Having somebody with the experience of Andy to do your test and work with you  makes a big difference. He was Amateur Xterra Triathlon World Champion in 2002, has competed in a number of World Cup XC Mountain Bike races and his practical experience is backed up with an Honours Degree in Sport and Human Movement Science.


Personally I would strongly recommend having one of these assessments done, they do cost north of £50 but they're worth it. If you are in the Bristol are check out True Zone, which is located in probably the best bike shop in Bristol: BW Cycling. However, if Bristol is too far, then try to find someone, or somewhere, that will consider more than just the VO2 Max number. You need to understand the finer details of your engine and then adjust your training programme accordingly, so try to find somewhere which offers a one-to-one consultation with an expert.

Whether you are aiming for a 5km Spartan Sprint or four laps of the Winter Nuts Challenge, running is at the heart of what we do, and there is more to running than putting one foot in front of the other.

Have a RAWSOME day!

Thanks to guest writer Scott Seedfeldt from RAW Obstacle Race Team for this article.

For more news , tips and info about obstacle course races and mud runs. Follow Mudstacle on: Twitter, Facebook and Youtube.


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