Lab vs Garmin VO2 MAX

My VO2 vs garments prediction

Some keen eyed viewers may notice that my maximum heart rate achieved only says I achieved 179bppm. I Eva gone back to them and asked if this is correct. They have come back to me with the data and found that that was for the lactate threshold testing. My maximum Hr on the vo2 test was 200bpm which as also adjusted my heart rate zones.

In this video I and some family members go for a vo2 max test at the Surrey sports park as part of Surrey university.
After the test I go over my data.

[greghouston]

This is exactly the kind of technical video I like to watch and learn from!

[ashleyhouse]

When it comes to "fat burning" in the athletic community I think there is a lot of confusion. What people really need to understand is not "why" but more appropriately "who" should be concerned with burning more fat over carbohydrates. As you have quite rightly identified the point at which we start to increasingly burn carbs over fat is the first lactate threshold or LT1.

If you are an ultra-endurance athlete concerned with Ironman triathlons or maybe and ultra-marathon runner then conservation of carbohydrates over many hours of competition at lower intensities have been shown to yield performance benefits over the whole race. However, if you are someone who is only concerned with ultimate speed over shorter distances, like a time-triallist for instance or a road racer, then worrying about fat burning is a waste of time. You are much more likely to be performing closer to LT2 for much of the time where you will be burning through your glycogen stores at a much higher rate.

For most normal non-fat adapted athletes like you and me, we will be burning around 0.5g of fat per minute at around LT1 or as you have shown in your graph 4-5 kcal/min. Again you have quite rightly stated that pro athletes can up that rate to around 1.2 g/min or 10-12 kcal/min. However, you won't appreciate what it takes to get to that level which is something like 18 months of a dedicated ketogenic diet which is tough. Not tough because it is particularly difficult to follow a ketogenic diet but tough because all the performance hits you will take in the first year to 18 months before the low carb diet starts to pay dividends. It will definitely leave you asking yourself “Why am I doing this?”

And in reality the benefits really only accrue to ultra-endurance athletes who are interested in going as far and as fast as they can for relatively long periods. Do a web search for Dr Dan Plews who is an expert in this field for more detailed information.

Another thing that was confirmed by the lab was that because you had eaten carbohydrates before the testing session, your fat utilisation was probably a bit low. This is because insulin is released to process the carbs you have eaten which also has the effect to cut off the burning of fat. In its simplest form, the body will tend to burn carbs in preference to fat to preserve your fat stores for what may be leaner times to come. This is why people tend to put on weight if they are eating a lot of carbs all the time as their insulin levels will be constantly high which also leads to insulin resistance and type 2 diabetes over time.

This is also the theory behind training fasted because you start to exercise with lower insulin levels which allow you to tap into your fat stores from the start. Training fasted is not about increasing performance though, it is about training to burn more fat if that is important to you.

My advice to the majority of amateur cyclists would be to forget about fat burning unless you really need to conserve glycogen stores over the long haul.

[davidsrunningvlog]

The Garmin is usually off when it comes to Vo2 max, but surprisingly can get close. I just had a Vo2 max test done last month and mine was 53. My Garmin had me at 55, so it wasn't too far off. My lactate threshold was 148 and Garmin was spot on, predicting 148 as well. However, the big miss was in max heart rate. Mine was 172 based on the test, but the Garmin had me at 184. This seriously altered my HR training zones (using % of max HR).

[jamesrowe]

Great video, it is really refreshing seeing someone more “normal” do this sort of testing. Personally my ftp is 255 and you watch all these cycling YouTubers who have 340 watt plus ftp’s and you start to think everyone is like that. But in reality I’m probably more on the normal side of things. 🤔 Keep up the great work. 👍🏻

[ccamire]

thanks for the video and sharing data. It helps everybody and especially me with lots of data points. I was surprised by the difference with Garmin. Like you said, your nutrition penalize you to bring more food on the ride. My fat curve is much higher. Eating more fat increased my lactate threshold to a higher power number.

[thedomesticsurvivalist]

Interesting to see the scientific data and particularly when you put it into context of your own race date, diet and training ranges - good work!

[attastealth]

Some comments on your results:
For sure your fat utilization was not high since you ate beforehand. We usually only see an RER/RQ of ~0.7 when people are fasted (100% fat utilization).

Secondly, we've had an issue in our lab when measuring max VO2 using breath-by-breath analysis (similar to the mask you wore). We have been finding (and with talking with the provider), that if you were able to finish your test holding a really high breathing rate (higher than 1 breath a second), the oxygen/CO2 probes do not have enough time to properly measure the values, resulting in an early plateau of measured VO2. So that could be one reason as to why your resultant VO2max was slightly lower than what you were expecting. If you have the raw data, it would be interesting to see when you hit your VO2plateau, how long you held it, and assess what your breathing frequency and Ve (L/min) were at those points.

I would also suggest comparing your absolute VO2 values to take into account small variances in your weight, and maybe doing another test in a couple of months to see your VO2 trainability (another factor that is somewhat genetically determined).

And lastly, while your VO2max values may not be as high as you hoped, the fact you've had some great performances shows that you might just be more efficient in the mechanical/power output side of things. Hitting 430W in your last ramp stage is no easy feat! I'm pushing similar numbers to you but have quite a bit more weight on my frame :)

Best of luck with the rest of your rehab journey and getting back to top shape.

[vitskr]

You should never care about specific number Garmin gives you. What you should care is dynamics, if you train properly this number goes up slowly. If it stays the same for a long time it means you need to change your routine.

[filiperibeiro]

Nice video but a rough estimate that may help to identify possible errors in the laboratory is the ratio of the cost of o2 per Watts at vo2max ~9-10mL/min/W. eg if vo2max happens at 400watts we can expect a VO2 of 3, 6-4 liters + ~800ml of pedal cost without load = total approximately 4.4-4.8L/min depending on the efficiency of the cyclist, numbers significantly higher than 3, 8L/min reported in your test.

[BobBob-uvfq]

It can give different readings depending on activities, ,maybe stronger in some areas than others, also think it depends on what type of excercise ie interval training or long run, low tempo etc

[michaelm]

Runner not a cyclist here, but my garmin watch estimates about 4ml/kg/min higher than my apple watch for whatever reason. I don't look at either as an actual estimate of my real VO2 max, more a general indication of my cardio fitness over time.

[mgdeburca]

Thanks for a really informative video. One question: in the final chart (showing your prescribed training zones) why is zone 6 labelled as VO2max and zone 5 is labelled anaerobic? It should be the other way round surely?

[mazzeumusic]

Great content! Thanks for the video. I'm curious about the table at the end. Shouldn't VO2Max come before Anaerobic, since anaerobic means no O2 utilization? Also very interesting the Fatmax curve! Never saw one like this. How much Z2 training you've been doing for the TTs prep? Tks!

[LaDeigo]

Great content, thanks for sharing your info.

[hebrewsvs]

Even if the power is slightly low, the speed is pretty quick. And at the end of the day, it's about how fast you are, not the power. I always guessed Garmin over exaggerated vo2 max. Now we know for sure.

[Nick_ia]

nice content! very very curious how diet and training fasted in middle of zone 2 will affect your performance :) waiting till then, cheers :)

[cfau]

Well i would not read all too much in single lab results...for example under lab conditions i severly underperform, may have to do with temp or staring at a wall while doing an effort alone and in the case you show there is a stationary bike used as well which can make a huge impact. I think your outdoor vo2 max may be higher.
On the other hand standard conditions in the lab allow the comparison of different collected data sets. So if you go to the same lab again it would be ideal to see if your rehab journey fruited in a higher vo2 max compared to the test done before! Good luck

[Janusandersen]

Cool video, thank you! Wonder why they, in the 6-zone model they sent you, didn't directly use physiological markers to set the endurance zone. E.g. align the top of zone 2 to LT1 for HR and power...

[allancox]

Thanks for putting this together, certainly something I'll be doing. Will you go back for a review and how long will you leave it? I'm thinking 6 monthly to see if I've progressed.

[PBlaik]

Interesting that this video popped up in my feed today.... I just did my first running Vo2 Max test today and the results were 59.4, which is higher than my Garmin's prediction of 54 which to be honest I expected was higher than real life... apparently it wasn't!!