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Portable replacement for a $60k VO2 Max machine

instructables.com

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Re: Portable replacement for a $60k VO2 Max machine

#81

Post by andreskytt »

dpeck wrote: post #44
trentnix wrote: post #18

This is really great. For those who aren't familiar with what these machines can do, the calculation of an athlete's Vo2 max really isn't all that useful. However, a breakdown of the fat and carbohydrate calories burned at various efforts can be incredibly useful for helping an athlete learn how to fuel correctly for performance over distance. I'm not a physiologist or physician (and I'm sure what I'm about to say ma…

I appreciate the modesty, but talking about completing an Ironman and having the phrase “really wasn't all that fit” anywhere near it is comical. Getting through any one of the stages of an Ironman (or heck even a half of each stage) represents a level of fitness most adults do not have and will never attain.

Not necessarily true, I think. It’s a mental barrier more, than a physical one. Tell someone you ran 100 m in 12 seconds and they go “meh”. Tell them you did a marathon and they go “i could not do that, awesome, how could you etc.” whereas an average person can do a marathon with a years worth of training and never achieve that sprint time.

It took for me 21 months of training to go from effectively zero to a half ironman and the biggest barrier was swimming, which is very technical in nature. I still can’t swim very well. I was in no shape at all and overweight. If you look at the speeds required to stay within ironman time limits, they are quite low and a person in a slightly better than average condition would be able to sustain them with relative ease. The barriers might be swimming technique (which one might have from training as a kid) and things like biking position and running technique but not necessarily fitness as such. In fact, I see quite a few people visually in much worse shape than I am (i.e. fatter) doing long IMs and beating me at shorter distances.

Re: Portable replacement for a $60k VO2 Max machine

#82

Post by vjk800 »

lhl wrote: post #78
ssl232 wrote: post #19

Earlier quoted context omitted.

A friend of mine does keto and after running a marathon reported that they did not experience "the wall". Presumably this is because they were using fat to begin with, not after mile 15 or whatever.

For those interested, Jeff Volek's team published a study in 2016, "Metabolic characteristics of keto-adapted ultra-endurance runners" [1] that compared fax oxidation. One of the "fat adapted" participants Zach Kibbter, an ultra-marathon record holder, posted a personal writeup that included a table of his fat usage at various VO2 Maxes (a ridiculous 98% fat usage at 75% VO2max and 76% even at 84% of VO2max!)[2] [1]…

What would those numbers be for the general population or someone who is slightly fit but not a freak?

Re: Portable replacement for a $60k VO2 Max machine

#83

Post by danielovichdk »

aix1 wrote: post #41
gameswithgo wrote: post #31

Earlier quoted context omitted.

The idea that fat efficiency can be improved via diet or training is often said, but the people I have known who both tried it and carefully measured it couldn’t. Also there are perfectly ordinary ways to figure out you need to eat more, Ive coached some pro cyclists and done a decent amount of my own triathlon and cycling adventures and if someone gave me a free vo2 machine I don’t think I would ever use it.

This is probably not exactly what you mean by diet, but Rob Gray (an Ultraman world champion) says: in the 10 days before the race I would predominantly eat a high fat diet. Based on all the testing I’ve done, what you eat in this window has a large impact on how your body uses fat vs carb on race day https://robgray.org/ironman-arizona-nutrition-report/

Carbo loading can be done prior to a race. The day before is usual. But even carbs in the morning before a race is effective.

The fat burning starts when you empty the glycogen chambers, but there is a sweet spot in terms of energy output, because as other people has pointed out, you can't do high intensity work on fat.

So it makes sense as an ultra endurance athlete that you try to pack som fat before a race, because it will be effective as a slow burning resource.

Another interesting thing at the moment are the ketones supplements one can drink.

Re: Portable replacement for a $60k VO2 Max machine

#84

Post by danielovichdk »

gameswithgo wrote: post #31
trentnix wrote: post #18

This is really great. For those who aren't familiar with what these machines can do, the calculation of an athlete's Vo2 max really isn't all that useful. However, a breakdown of the fat and carbohydrate calories burned at various efforts can be incredibly useful for helping an athlete learn how to fuel correctly for performance over distance. I'm not a physiologist or physician (and I'm sure what I'm about to say ma…

The idea that fat efficiency can be improved via diet or training is often said, but the people I have known who both tried it and carefully measured it couldn’t. Also there are perfectly ordinary ways to figure out you need to eat more, Ive coached some pro cyclists and done a decent amount of my own triathlon and cycling adventures and if someone gave me a free vo2 machine I don’t think I would ever use it.

Which pro cyclists have you trained ?

Re: Portable replacement for a $60k VO2 Max machine

#85

Post by iamacyborg »

trentnix wrote: post #18

This is really great. For those who aren't familiar with what these machines can do, the calculation of an athlete's Vo2 max really isn't all that useful. However, a breakdown of the fat and carbohydrate calories burned at various efforts can be incredibly useful for helping an athlete learn how to fuel correctly for performance over distance. I'm not a physiologist or physician (and I'm sure what I'm about to say ma…

> the calculation of an athlete's Vo2 max really isn't all that useful

I can hear thousands of Garmin owners screaming about this comment as they obsess over their VO2 Max.

Re: Portable replacement for a $60k VO2 Max machine

#86

Post by C19is20 »

ghastmaster wrote: post #3

The title should be changed to reflect the title used in the article. "Accurate VO2 Max for Zwift and Strava" Especially considering the following: > Physiology labs that are normally used for testing VO2 max cost upwards of $60,000 and are certainly not portable. They have sensors that measure the same things only on a much finer level.

Check out intervals.icu

Re: Portable replacement for a $60k VO2 Max machine

#87

Post by SergeAx »

Wow, great job! That's the real hacker spirit)

> I have found that with the calculations for energy expended from the Oxygen utilization algorithm is slightly higher than that calculated by the work/watt output of the Zwift App algorithm.

I beleive this is because Zwift doesn't count a basal metabolic rate. As far as I understand this is a default behavior for all calorie tables and trackers, one must calculate and add that constant manually. This device can actually measure that value!

Re: Portable replacement for a $60k VO2 Max machine

#88

Post by thelittleone »

trentnix wrote: post #70
moneywoes wrote: post #68

Earlier quoted context omitted.

How much running training did you do and if you don't mind sharing what was your marathon time?

When I started I was able to run a 5k and that was about it. I trained for 21 or 22 weeks. I think my marathon was a 5:30 or something like that. Lots of walking, but I never stopped moving.

Respect for achieving that in 21 weeks.

Re: Portable replacement for a $60k VO2 Max machine

#89

Post by idealmedtech »

xondono wrote: post #47
hprotagonist wrote: post #15

Earlier quoted context omitted.

Most of them are written in blood.

You are assuming that the existence of regulations means that there’s testing required. You’d be surprised at how much is just about filling the proper paperwork, paying some fees and knowing the right people. The amount of independent testing is negligible.

I'm sorry, but this is just patently false. The FDA requires extensive V&V testing, especially for medical devices that have a significant chance to kill the people that it's used on. That, and you need to have a very sophisticated quality management system (QMS) in place that tracks all the changes you make during your design and test process, links up source requirements to passing test reports in an auditable way, tracks all of your manufacturing information (including which batches were tested using what procedures, and the results), all of which can be randomly audited at any time, no matter where the facility is located on the world.

You may be referring to the 510k (pre-existing predicate device) pathway, which has been abused by companies to leapfrog and skip _some_ of the more stringent test requirements, but they still need to prove similarities, and that requires real data. However, in the vast majority of cases, these devices are things like masks, IV tubing sets, etc, not complex life saving equipment, which gets an enormous amount of scrutiny. If anything, it's the medical device companies that are at fault for lobbying Congress to allow abuse of 510k pathways, and Congress for allowing these things to happen.

Re: Portable replacement for a $60k VO2 Max machine

#90

Post by DrOctagon »

panabee wrote: post #76
trentnix wrote: post #18

This is really great. For those who aren't familiar with what these machines can do, the calculation of an athlete's Vo2 max really isn't all that useful. However, a breakdown of the fat and carbohydrate calories burned at various efforts can be incredibly useful for helping an athlete learn how to fuel correctly for performance over distance. I'm not a physiologist or physician (and I'm sure what I'm about to say ma…

could you kindly elaborate on why Vo2 max isn't useful for an athlete? naively, it seems measuring oxygen consumption would be useful.

It’s been a while since I’ve read much about this but one explanation I’ve heard is that Vo2 was elevated to importance because it could be accurately measured and therefore studied.

Also unlike aerobic fitness, which can be improved with year after year of consistent training, an athletes peak Vo2 max (for their given fitness) can be maxed out over 4 - 6 weeks of specific training. Doing much more specific Vo2 training can result the athlete (at least in running) becoming ‘flat’.

That said Vo2 measurement can provide a great deal of useful information but for most recreational athletes getting the basics right is more important than having an exact Vo2 measurement.

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